diff --git a/.changeset/zod-4-support.md b/.changeset/zod-4-support.md
new file mode 100644
index 00000000000..ef90f6396e3
--- /dev/null
+++ b/.changeset/zod-4-support.md
@@ -0,0 +1,14 @@
+---
+"@trigger.dev/build": minor
+"@trigger.dev/core": minor
+"@trigger.dev/react-hooks": minor
+"@trigger.dev/rsc": minor
+"@trigger.dev/sdk": minor
+"trigger.dev": minor
+"@trigger.dev/redis-worker": minor
+"@trigger.dev/schema-to-json": minor
+---
+
+Add Zod 4 support. You can now use Zod 3.25.76+ or Zod 4.
+
+Zod remains a runtime dependency of packages that execute schemas, so existing and new installations continue to receive it automatically. The matching peer dependency range allows package managers to reuse either a compatible Zod 3 or Zod 4 installation from your project.
diff --git a/AGENTS.md b/AGENTS.md
index cc947c7a57d..e459a74c9c6 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -108,7 +108,7 @@ When modifying only server components (`apps/webapp/`, `apps/supervisor/`, etc.)
 
 ## Dependency Pinning
 
-Zod is pinned to a single version across the entire monorepo (currently `3.25.76`). When adding zod to a new or existing package, use the **exact same version** as the rest of the repo - never a different version or a range. Mismatched zod versions cause runtime type incompatibilities (e.g., schemas from one package can't be used as body validators in another).
+Zod is pinned to a single version across the entire monorepo (currently `4.4.3`). When adding zod to a new or existing package, use the **exact same version** as the rest of the repo - never a different version or a range. Mismatched zod versions cause runtime type incompatibilities (e.g., schemas from one package can't be used as body validators in another).
 
 ## Architecture Overview
 
diff --git a/apps/supervisor/package.json b/apps/supervisor/package.json
index 2725fe2b729..d4555061708 100644
--- a/apps/supervisor/package.json
+++ b/apps/supervisor/package.json
@@ -23,7 +23,7 @@
     "prom-client": "^15.1.0",
     "socket.io": "4.7.4",
     "std-env": "^3.8.0",
-    "zod": "3.25.76"
+    "zod": "4.4.3"
   },
   "devDependencies": {
     "@internal/testcontainers": "workspace:*",
diff --git a/apps/webapp/app/components/Feedback.tsx b/apps/webapp/app/components/Feedback.tsx
index b679b042da1..d7204dde41a 100644
--- a/apps/webapp/app/components/Feedback.tsx
+++ b/apps/webapp/app/components/Feedback.tsx
@@ -5,7 +5,7 @@ import {
   getTextareaProps,
   useForm,
 } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { InformationCircleIcon, ArrowUpCircleIcon } from "@heroicons/react/20/solid";
 import { EnvelopeIcon, ShieldCheckIcon } from "@heroicons/react/24/solid";
 import { Form, useActionData, useLocation, useNavigation, useSearchParams } from "@remix-run/react";
@@ -129,7 +129,7 @@ export function Feedback({
             <Fieldset className="max-w-full gap-y-3">
               <input
                 value={location.pathname}
-                {...getInputProps(fields.path, { type: "hidden" })}
+                {...getInputProps(fields.path, { type: "hidden", value: false })}
               />
               <InputGroup className="max-w-full">
                 {type === "feature" && (
diff --git a/apps/webapp/app/components/billing/BillingAlertsSection.tsx b/apps/webapp/app/components/billing/BillingAlertsSection.tsx
index ce2f5e5e0fc..7d85e9880b0 100644
--- a/apps/webapp/app/components/billing/BillingAlertsSection.tsx
+++ b/apps/webapp/app/components/billing/BillingAlertsSection.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, getInputProps, useForm, type SubmissionResult } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { PlusIcon, TrashIcon } from "@heroicons/react/20/solid";
 import { Form, useActionData, useSearchParams } from "@remix-run/react";
 import { Fragment, useEffect, useMemo, useRef, useState } from "react";
diff --git a/apps/webapp/app/components/billing/BillingLimitConfigSection.tsx b/apps/webapp/app/components/billing/BillingLimitConfigSection.tsx
index e6362d4cb1d..675f444c6f6 100644
--- a/apps/webapp/app/components/billing/BillingLimitConfigSection.tsx
+++ b/apps/webapp/app/components/billing/BillingLimitConfigSection.tsx
@@ -1,6 +1,6 @@
 import { getFormProps, useForm, type SubmissionResult } from "@conform-to/react";
 
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { Form, useActionData } from "@remix-run/react";
 import { useEffect, useMemo, useRef, useState } from "react";
 import { z } from "zod";
@@ -37,7 +37,7 @@ export const billingLimitFormSchema = z.discriminatedUnion("mode", [
   z.object({
     mode: z.literal("custom"),
     amount: z.coerce
-      .number({ invalid_type_error: "Not a valid amount" })
+      .number({ error: "Not a valid amount" })
       .positive("Amount must be greater than 0"),
     cancelInProgressRuns: z
       .preprocess((v) => v === "on" || v === true || v === "true", z.boolean())
diff --git a/apps/webapp/app/components/billing/BillingLimitRecoveryPanel.tsx b/apps/webapp/app/components/billing/BillingLimitRecoveryPanel.tsx
index 1dfcdd73707..c0ecbc402c2 100644
--- a/apps/webapp/app/components/billing/BillingLimitRecoveryPanel.tsx
+++ b/apps/webapp/app/components/billing/BillingLimitRecoveryPanel.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, useForm, type SubmissionResult } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { Form, useActionData, useNavigation } from "@remix-run/react";
 import { useEffect, useMemo, useRef, useState } from "react";
 import { z } from "zod";
@@ -21,7 +21,7 @@ export const billingLimitRecoveryFormSchema = z
   .object({
     action: z.enum(["increase", "remove"]),
     newAmount: z.coerce
-      .number({ invalid_type_error: "Not a valid amount" })
+      .number({ error: "Not a valid amount" })
       .positive("Amount must be greater than 0")
       .optional(),
     resumeMode: z.enum(["queue", "new_only"]),
@@ -87,7 +87,7 @@ export function BillingLimitRecoveryPanel({
     },
     defaultValue: {
       action: "increase",
-      newAmount: suggestedNewLimitDollars,
+      newAmount: String(suggestedNewLimitDollars),
       resumeMode: "queue",
     },
   });
diff --git a/apps/webapp/app/components/errors/ConfigureErrorAlerts.tsx b/apps/webapp/app/components/errors/ConfigureErrorAlerts.tsx
index b126e77b34b..fe43b7a794f 100644
--- a/apps/webapp/app/components/errors/ConfigureErrorAlerts.tsx
+++ b/apps/webapp/app/components/errors/ConfigureErrorAlerts.tsx
@@ -1,6 +1,6 @@
 import { getFormProps, getInputProps, useForm } from "@conform-to/react";
 import { GlobeLinesIcon } from "~/assets/icons/GlobeLinesIcon";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { EnvelopeIcon, HashtagIcon, LockClosedIcon, XMarkIcon } from "@heroicons/react/20/solid";
 import { BellAlertIcon } from "@heroicons/react/24/solid";
 import { useFetcher, useNavigate } from "@remix-run/react";
diff --git a/apps/webapp/app/components/metrics/QueryWidget.tsx b/apps/webapp/app/components/metrics/QueryWidget.tsx
index 9f821816046..564f3e27718 100644
--- a/apps/webapp/app/components/metrics/QueryWidget.tsx
+++ b/apps/webapp/app/components/metrics/QueryWidget.tsx
@@ -55,7 +55,7 @@ const chartConfigOptions = {
   sortByColumn: z.string().nullable(),
   sortDirection: SortDirection,
   aggregation: AggregationType,
-  seriesColors: z.record(z.string()).optional(),
+  seriesColors: z.record(z.string(), z.string()).optional(),
 };
 
 const ChartConfiguration = z.object({ ...chartConfigOptions });
diff --git a/apps/webapp/app/components/runs/v3/ReplayRunDialog.tsx b/apps/webapp/app/components/runs/v3/ReplayRunDialog.tsx
index 86747f9e277..a54344bad03 100644
--- a/apps/webapp/app/components/runs/v3/ReplayRunDialog.tsx
+++ b/apps/webapp/app/components/runs/v3/ReplayRunDialog.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, getInputProps, getSelectProps, useForm } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { RectangleStackIcon } from "@heroicons/react/20/solid";
 import { DialogClose } from "@radix-ui/react-dialog";
 import { Form, useActionData, useNavigation, useParams, useSubmit } from "@remix-run/react";
diff --git a/apps/webapp/app/components/schedules/PurchaseSchedulesModal.tsx b/apps/webapp/app/components/schedules/PurchaseSchedulesModal.tsx
index 3054a0cdf48..428389e129b 100644
--- a/apps/webapp/app/components/schedules/PurchaseSchedulesModal.tsx
+++ b/apps/webapp/app/components/schedules/PurchaseSchedulesModal.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, useForm } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { EnvelopeIcon } from "@heroicons/react/20/solid";
 import { DialogClose } from "@radix-ui/react-dialog";
 import { useFetcher } from "@remix-run/react";
diff --git a/apps/webapp/app/models/orgIntegration.server.ts b/apps/webapp/app/models/orgIntegration.server.ts
index f2bd0feebce..f136c9cb483 100644
--- a/apps/webapp/app/models/orgIntegration.server.ts
+++ b/apps/webapp/app/models/orgIntegration.server.ts
@@ -22,7 +22,7 @@ const SlackSecretSchema = z.object({
   refreshToken: z.string().optional(),
   botScopes: z.array(z.string()).optional(),
   userScopes: z.array(z.string()).optional(),
-  raw: z.record(z.any()).optional(),
+  raw: z.record(z.string(), z.any()).optional(),
 });
 
 type SlackSecret = z.infer<typeof SlackSecretSchema>;
diff --git a/apps/webapp/app/models/vercelIntegration.server.ts b/apps/webapp/app/models/vercelIntegration.server.ts
index 3a1aaf4b8ea..324a1651270 100644
--- a/apps/webapp/app/models/vercelIntegration.server.ts
+++ b/apps/webapp/app/models/vercelIntegration.server.ts
@@ -129,7 +129,7 @@ export const VercelSecretSchema = z.object({
   teamId: z.string().nullable().optional(),
   userId: z.string().optional(),
   installationId: z.string().optional(),
-  raw: z.record(z.any()).optional(),
+  raw: z.record(z.string(), z.any()).optional(),
 });
 
 export type VercelSecret = z.infer<typeof VercelSecretSchema>;
diff --git a/apps/webapp/app/models/vercelSdkRecovery.server.ts b/apps/webapp/app/models/vercelSdkRecovery.server.ts
index d3e1bfd6961..31253fe430e 100644
--- a/apps/webapp/app/models/vercelSdkRecovery.server.ts
+++ b/apps/webapp/app/models/vercelSdkRecovery.server.ts
@@ -145,11 +145,11 @@ export const VercelSchemas = {
     .union([
       z
         .object({
-          envs: z.array(z.record(z.unknown())),
+          envs: z.array(z.record(z.string(), z.unknown())),
           pagination: z.unknown().optional(),
         })
         .passthrough(),
-      z.array(z.record(z.unknown())),
+      z.array(z.record(z.string(), z.unknown())),
     ])
     .transform((val) => (Array.isArray(val) ? { envs: val } : val)),
 
diff --git a/apps/webapp/app/presenters/v3/MetricDashboardPresenter.server.ts b/apps/webapp/app/presenters/v3/MetricDashboardPresenter.server.ts
index 0b84e971b2f..5c43a7ff63c 100644
--- a/apps/webapp/app/presenters/v3/MetricDashboardPresenter.server.ts
+++ b/apps/webapp/app/presenters/v3/MetricDashboardPresenter.server.ts
@@ -48,7 +48,7 @@ export const DashboardLayout = z.discriminatedUnion("version", [
   z.object({
     version: z.literal("1"),
     layout: z.array(LayoutItem),
-    widgets: z.record(Widget),
+    widgets: z.record(z.string(), Widget),
   }),
 ]);
 
diff --git a/apps/webapp/app/presenters/v3/SpanPresenter.server.ts b/apps/webapp/app/presenters/v3/SpanPresenter.server.ts
index b680a1c6a8e..209e906e50f 100644
--- a/apps/webapp/app/presenters/v3/SpanPresenter.server.ts
+++ b/apps/webapp/app/presenters/v3/SpanPresenter.server.ts
@@ -1024,6 +1024,9 @@ export class SpanPresenter extends BasePresenter {
         filePath: lockedWorker?.lockedBy?.filePath ?? "",
       },
       run: {
+        // zod v4 types the run-context `context` (z.any) field as required; it was
+        // never populated here (optional under v3), so undefined preserves behavior.
+        context: undefined,
         id: run.friendlyId,
         createdAt: run.createdAt,
         tags: run.runTags,
diff --git a/apps/webapp/app/routes/_app.orgs.$organizationSlug.invite/route.tsx b/apps/webapp/app/routes/_app.orgs.$organizationSlug.invite/route.tsx
index b6fe0b09c68..b51a6d5ae1a 100644
--- a/apps/webapp/app/routes/_app.orgs.$organizationSlug.invite/route.tsx
+++ b/apps/webapp/app/routes/_app.orgs.$organizationSlug.invite/route.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, getInputProps, useForm } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import {
   ArrowUpCircleIcon,
   EnvelopeIcon,
diff --git a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.alerts.new/route.tsx b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.alerts.new/route.tsx
index f121900e901..275f6556eb3 100644
--- a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.alerts.new/route.tsx
+++ b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.alerts.new/route.tsx
@@ -1,11 +1,11 @@
 import { getFormProps, getInputProps, getSelectProps, useForm } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { HashtagIcon, LockClosedIcon } from "@heroicons/react/20/solid";
 import { Form, useActionData, useNavigate, useNavigation } from "@remix-run/react";
 import { type LoaderFunctionArgs } from "@remix-run/router";
 import { type ActionFunctionArgs, json } from "@remix-run/server-runtime";
 import { SlackIcon } from "@trigger.dev/companyicons";
-import { useEffect, useRef, useState } from "react";
+import { useEffect, useState } from "react";
 import { typedjson, useTypedLoaderData } from "remix-typedjson";
 import { z } from "zod";
 import { InlineCode } from "~/components/code/InlineCode";
@@ -233,7 +233,6 @@ export default function Page() {
   const project = useProject();
   const environment = useEnvironment();
   const [currentAlertChannel, setCurrentAlertChannel] = useState<string | null>(option ?? "EMAIL");
-  const formRef = useRef<HTMLFormElement>(null);
 
   const [selectedSlackChannelValue, setSelectedSlackChannelValue] = useState<string | undefined>();
 
@@ -267,7 +266,7 @@ export default function Page() {
     if (navigation.state !== "idle") return;
     if (lastSubmission !== undefined) return;
 
-    formRef.current?.reset();
+    form.reset();
   }, [navigation.state, lastSubmission]);
 
   return (
@@ -281,7 +280,7 @@ export default function Page() {
     >
       <DialogContent>
         <DialogHeader>New alert</DialogHeader>
-        <Form ref={formRef} method="post" {...getFormProps(form)}>
+        <Form method="post" {...getFormProps(form)}>
           <Fieldset className="mt-2">
             <InputGroup fullWidth>
               <SegmentedControl
diff --git a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.alerts/route.tsx b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.alerts/route.tsx
index 62ecec6890f..59ae47da491 100644
--- a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.alerts/route.tsx
+++ b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.alerts/route.tsx
@@ -1,6 +1,6 @@
 import { getFormProps, useForm } from "@conform-to/react";
 import { GlobeLinesIcon } from "~/assets/icons/GlobeLinesIcon";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import {
   BellAlertIcon,
   BellSlashIcon,
diff --git a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.branches/route.tsx b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.branches/route.tsx
index 909a8bb6381..327fc684360 100644
--- a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.branches/route.tsx
+++ b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.branches/route.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, getInputProps, useForm } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { ArrowUpCircleIcon, CheckIcon, EnvelopeIcon, PlusIcon } from "@heroicons/react/20/solid";
 import { BookOpenIcon } from "@heroicons/react/24/solid";
 import { DialogClose } from "@radix-ui/react-dialog";
diff --git a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.concurrency/route.tsx b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.concurrency/route.tsx
index e9542b5c8f5..20c08c88447 100644
--- a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.concurrency/route.tsx
+++ b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.concurrency/route.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, getInputProps, useForm } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import {
   ArrowDownIcon,
   EnvelopeIcon,
@@ -480,7 +480,7 @@ function Upgradable({
               </TableRow>
             </TableBody>
           </Table>
-          <FormError id={formEnvironments.id}>{formEnvironments.errors}</FormError>
+          <FormError id={formEnvironments.errorId}>{formEnvironments.errors}</FormError>
         </div>
         <Form className="flex flex-col gap-2" method="post" {...getFormProps(form)} id="allocate">
           <input type="hidden" name="action" value="allocate" />
diff --git a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.environment-variables.new/route.tsx b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.environment-variables.new/route.tsx
index 02d6ef00c4d..1c397e3eddf 100644
--- a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.environment-variables.new/route.tsx
+++ b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.environment-variables.new/route.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, useForm, type FieldMetadata, type FormMetadata } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import {
   LockClosedIcon,
   LockOpenIcon,
@@ -88,7 +88,7 @@ const schema = z.object({
 
       return;
     },
-    z.array(z.string(), { required_error: "At least one environment is required" })
+    z.array(z.string(), { error: "At least one environment is required" })
   ),
   variables: z.preprocess((i) => {
     if (!Array.isArray(i)) {
@@ -247,9 +247,9 @@ export default function Page() {
   const [selectedEnvironmentIds, setSelectedEnvironmentIds] = useState<Set<string>>(new Set());
   const [selectedBranchId, setSelectedBranchId] = useState<string | undefined>(undefined);
 
-  // TODO for no we only support branch-specific env vars for Preview environments
-  // Mostly to keep the UX for setting consistent env-vars across Dev/Staging/Prod easier
-  const previewBranches = environments.filter(
+  // TODO: we only support branch-specific env vars for Preview environments.
+  // This keeps setting consistent env vars across Dev/Staging/Prod easier.
+  const branchEnvironments = environments.filter(
     (env) => env.type === "PREVIEW" && env.parentEnvironmentId !== null
   );
   const nonBranchEnvironments = environments.filter((env) => env.parentEnvironmentId === null);
@@ -436,7 +436,7 @@ export default function Page() {
                     value={selectedBranchId ?? "all"}
                     setValue={handleBranchChange}
                     placeholder="All branches"
-                    items={[{ id: "all", branchName: "All branches" }, ...previewBranches]}
+                    items={[{ id: "all", branchName: "All branches" }, ...branchEnvironments]}
                     className="w-fit min-w-52"
                     filter={{
                       keys: [
@@ -444,7 +444,7 @@ export default function Page() {
                       ],
                     }}
                     text={(val) =>
-                      val ? previewBranches.find((b) => b.id === val)?.branchName : null
+                      val ? branchEnvironments.find((b) => b.id === val)?.branchName : null
                     }
                     dropdownIcon
                   >
diff --git a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.environment-variables/route.tsx b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.environment-variables/route.tsx
index bd152e58033..d53c28df3cb 100644
--- a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.environment-variables/route.tsx
+++ b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.environment-variables/route.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, getInputProps, useForm } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import {
   BookOpenIcon,
   InformationCircleIcon,
diff --git a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.errors.$fingerprint/route.tsx b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.errors.$fingerprint/route.tsx
index 6ec1aa7fce1..1b23b80390b 100644
--- a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.errors.$fingerprint/route.tsx
+++ b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.errors.$fingerprint/route.tsx
@@ -1,4 +1,4 @@
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { BellAlertIcon } from "@heroicons/react/20/solid";
 import { type MetaFunction, useFetcher, useRevalidator } from "@remix-run/react";
 import { type ActionFunctionArgs, json, type LoaderFunctionArgs } from "@remix-run/server-runtime";
diff --git a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.errors/route.tsx b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.errors/route.tsx
index 769a4868266..7ed9502b375 100644
--- a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.errors/route.tsx
+++ b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.errors/route.tsx
@@ -1,4 +1,4 @@
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { Outlet, useNavigate } from "@remix-run/react";
 import { type ActionFunctionArgs, type LoaderFunctionArgs, json } from "@remix-run/server-runtime";
 import { useCallback } from "react";
diff --git a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.query/route.tsx b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.query/route.tsx
index 4f5a2c1e52d..5c8a7b77fd7 100644
--- a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.query/route.tsx
+++ b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.query/route.tsx
@@ -160,7 +160,7 @@ export const action = async ({ request, params }: ActionFunctionArgs) => {
   if (!parsed.success) {
     return typedjson(
       {
-        error: parsed.error.errors.map((e) => e.message).join(", "),
+        error: parsed.error.issues.map((e) => e.message).join(", "),
         rows: null,
         columns: null,
         stats: null,
diff --git a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.schedules.$scheduleParam/route.tsx b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.schedules.$scheduleParam/route.tsx
index a3a0ef05470..3d154e26289 100644
--- a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.schedules.$scheduleParam/route.tsx
+++ b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.schedules.$scheduleParam/route.tsx
@@ -1,4 +1,4 @@
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { useLocation } from "@remix-run/react";
 import { type ActionFunctionArgs, type LoaderFunctionArgs, json } from "@remix-run/server-runtime";
 import { typedjson, useTypedLoaderData } from "remix-typedjson";
diff --git a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.settings.general/route.tsx b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.settings.general/route.tsx
index ccc61fc5ac9..c2f3ec2aa22 100644
--- a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.settings.general/route.tsx
+++ b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.settings.general/route.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, getInputProps, useForm } from "@conform-to/react";
-import { conformZodMessage, parseWithZod } from "@conform-to/zod";
+import { conformZodMessage, parseWithZod } from "@conform-to/zod/v4";
 import { ExclamationTriangleIcon, FolderIcon, TrashIcon } from "@heroicons/react/20/solid";
 import { Form, useActionData, useNavigation } from "@remix-run/react";
 import { json } from "@remix-run/server-runtime";
diff --git a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.settings.integrations/route.tsx b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.settings.integrations/route.tsx
index 9bc54b19bf1..706aad4d860 100644
--- a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.settings.integrations/route.tsx
+++ b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.settings.integrations/route.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, getInputProps, useForm } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { Form, useActionData, useNavigation, useSearchParams } from "@remix-run/react";
 import { json } from "@remix-run/server-runtime";
 import React, { useCallback, useEffect, useRef, useState } from "react";
diff --git a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.test.tasks.$taskParam/route.tsx b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.test.tasks.$taskParam/route.tsx
index ffe6dbcd038..87ddb127205 100644
--- a/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.test.tasks.$taskParam/route.tsx
+++ b/apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.test.tasks.$taskParam/route.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, getInputProps, getSelectProps, useForm } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import {
   CheckCircleIcon,
   RectangleStackIcon,
@@ -433,37 +433,15 @@ function StandardTaskForm({
 
   const [showTemplateCreatedSuccessMessage, setShowTemplateCreatedSuccessMessage] = useState(false);
 
-  const [
-    form,
-    {
-      environmentId,
-      payload,
-      metadata,
-      taskIdentifier,
-      delaySeconds,
-      ttlSeconds,
-      idempotencyKey,
-      idempotencyKeyTTLSeconds,
-      queue,
-      concurrencyKey,
-      maxAttempts,
-      maxDurationSeconds,
-      triggerSource,
-      tags,
-      version,
-      machine,
-      region,
-      prioritySeconds,
-    },
-  ] = useForm({
+  const [form, fields] = useForm({
     id: "test-task",
     // TODO: type this
     lastResult: lastSubmission as any,
     onSubmit(event, { formData }) {
       event.preventDefault();
 
-      formData.set(payload.name, currentPayloadJson.current);
-      formData.set(metadata.name, currentMetadataJson.current);
+      formData.set(fields.payload.name, currentPayloadJson.current);
+      formData.set(fields.metadata.name, currentMetadataJson.current);
 
       submit(formData, { method: "POST" });
     },
@@ -471,6 +449,24 @@ function StandardTaskForm({
       return parseWithZod(formData, { schema: TestTaskData });
     },
   });
+  const {
+    environmentId,
+    taskIdentifier,
+    delaySeconds,
+    ttlSeconds,
+    idempotencyKey,
+    idempotencyKeyTTLSeconds,
+    queue,
+    concurrencyKey,
+    maxAttempts,
+    maxDurationSeconds,
+    triggerSource,
+    tags,
+    version,
+    machine,
+    region,
+    prioritySeconds,
+  } = fields;
 
   return (
     <Form className="flex h-full max-h-full flex-col" method="post" {...getFormProps(form)}>
diff --git a/apps/webapp/app/routes/_app.orgs.$organizationSlug.settings._index/route.tsx b/apps/webapp/app/routes/_app.orgs.$organizationSlug.settings._index/route.tsx
index 348658ba9ef..29c1e0c26f8 100644
--- a/apps/webapp/app/routes/_app.orgs.$organizationSlug.settings._index/route.tsx
+++ b/apps/webapp/app/routes/_app.orgs.$organizationSlug.settings._index/route.tsx
@@ -1,6 +1,6 @@
 import colorWheelIcon from "../../assets/images/color-wheel.png";
 import { getFormProps, getInputProps, useForm } from "@conform-to/react";
-import { conformZodMessage, parseWithZod } from "@conform-to/zod";
+import { conformZodMessage, parseWithZod } from "@conform-to/zod/v4";
 import {
   CheckIcon,
   ExclamationTriangleIcon,
diff --git a/apps/webapp/app/routes/_app.orgs.$organizationSlug.settings.billing-limits/route.tsx b/apps/webapp/app/routes/_app.orgs.$organizationSlug.settings.billing-limits/route.tsx
index a7790c4ee48..c61bbe72b8f 100644
--- a/apps/webapp/app/routes/_app.orgs.$organizationSlug.settings.billing-limits/route.tsx
+++ b/apps/webapp/app/routes/_app.orgs.$organizationSlug.settings.billing-limits/route.tsx
@@ -1,4 +1,4 @@
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import type { MetaFunction } from "@remix-run/react";
 import { json, redirect } from "@remix-run/server-runtime";
 import { tryCatch } from "@trigger.dev/core";
diff --git a/apps/webapp/app/routes/_app.orgs.$organizationSlug.settings.private-connections.new/route.tsx b/apps/webapp/app/routes/_app.orgs.$organizationSlug.settings.private-connections.new/route.tsx
index 1dc9753ac13..888d30c681a 100644
--- a/apps/webapp/app/routes/_app.orgs.$organizationSlug.settings.private-connections.new/route.tsx
+++ b/apps/webapp/app/routes/_app.orgs.$organizationSlug.settings.private-connections.new/route.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, getInputProps, getSelectProps, useForm } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { Form, useActionData, useParams, type MetaFunction } from "@remix-run/react";
 import { json, type ActionFunction, type LoaderFunctionArgs } from "@remix-run/server-runtime";
 import { tryCatch } from "@trigger.dev/core/utils";
diff --git a/apps/webapp/app/routes/_app.orgs.$organizationSlug.settings.team/route.tsx b/apps/webapp/app/routes/_app.orgs.$organizationSlug.settings.team/route.tsx
index cc2a95571d0..2212a69828d 100644
--- a/apps/webapp/app/routes/_app.orgs.$organizationSlug.settings.team/route.tsx
+++ b/apps/webapp/app/routes/_app.orgs.$organizationSlug.settings.team/route.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, getInputProps, useForm } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { EnvelopeIcon, NoSymbolIcon, UserPlusIcon } from "@heroicons/react/20/solid";
 import { DialogClose } from "@radix-ui/react-dialog";
 import {
@@ -1062,7 +1062,7 @@ export function PurchaseSeatsModal({
                   Total extra seats
                 </Label>
                 <InputNumberStepper
-                  {...getInputProps(amount, { type: "number" })}
+                  {...getInputProps(amount, { type: "number", value: false })}
                   step={seatPricing.stepSize}
                   min={0}
                   max={undefined}
diff --git a/apps/webapp/app/routes/_app.orgs.$organizationSlug_.projects.new/route.tsx b/apps/webapp/app/routes/_app.orgs.$organizationSlug_.projects.new/route.tsx
index 70c07a6dfcb..b58ab15b768 100644
--- a/apps/webapp/app/routes/_app.orgs.$organizationSlug_.projects.new/route.tsx
+++ b/apps/webapp/app/routes/_app.orgs.$organizationSlug_.projects.new/route.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, getInputProps, useForm } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { CommandLineIcon, FolderIcon } from "@heroicons/react/20/solid";
 import { json, type ActionFunction, type LoaderFunctionArgs } from "@remix-run/node";
 import { Form, useActionData, useNavigation } from "@remix-run/react";
@@ -388,12 +388,12 @@ export default function Page() {
                 </InputGroup>
                 {canCreateV3Projects ? (
                   <input
-                    {...getInputProps(projectVersion, { type: "hidden" })}
+                    {...getInputProps(projectVersion, { type: "hidden", value: false })}
                     defaultValue={"v3"}
                   />
                 ) : (
                   <input
-                    {...getInputProps(projectVersion, { type: "hidden" })}
+                    {...getInputProps(projectVersion, { type: "hidden", value: false })}
                     defaultValue={"v2"}
                   />
                 )}
diff --git a/apps/webapp/app/routes/_app.orgs.new/route.tsx b/apps/webapp/app/routes/_app.orgs.new/route.tsx
index b06d9bafd93..d676d21a338 100644
--- a/apps/webapp/app/routes/_app.orgs.new/route.tsx
+++ b/apps/webapp/app/routes/_app.orgs.new/route.tsx
@@ -1,6 +1,6 @@
 import { getFormProps, getInputProps, useForm } from "@conform-to/react";
 import { GlobeLinesIcon } from "~/assets/icons/GlobeLinesIcon";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { BuildingOffice2Icon } from "@heroicons/react/20/solid";
 import { RadioGroup } from "@radix-ui/react-radio-group";
 import { json, redirect, type ActionFunction, type LoaderFunctionArgs } from "@remix-run/node";
diff --git a/apps/webapp/app/routes/account._index/route.tsx b/apps/webapp/app/routes/account._index/route.tsx
index 4ecccb33d68..94969a30239 100644
--- a/apps/webapp/app/routes/account._index/route.tsx
+++ b/apps/webapp/app/routes/account._index/route.tsx
@@ -1,6 +1,6 @@
 import { getFormProps, getInputProps, useForm } from "@conform-to/react";
 import { useEffect, useState } from "react";
-import { conformZodMessage, parseWithZod } from "@conform-to/zod";
+import { conformZodMessage, parseWithZod } from "@conform-to/zod/v4";
 import { ComputerDesktopIcon, MoonIcon, SunIcon, SwatchIcon } from "@heroicons/react/20/solid";
 import {
   Form,
@@ -90,9 +90,9 @@ function createSchema(
 ) {
   return z.object({
     name: z
-      .string({ required_error: "You must enter a name" })
+      .string({ error: "You must enter a name" })
       .min(2, "Your name must be at least 2 characters long")
-      .max(50),
+      .max(50, "Your name must be 50 characters or less"),
     email: emailSchema.pipe(
       z.string().superRefine((email, ctx) => {
         if (constraints.isEmailUnique === undefined) {
diff --git a/apps/webapp/app/routes/account.tokens/route.tsx b/apps/webapp/app/routes/account.tokens/route.tsx
index 1179d070ead..63baccf8f2b 100644
--- a/apps/webapp/app/routes/account.tokens/route.tsx
+++ b/apps/webapp/app/routes/account.tokens/route.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, getInputProps, useForm } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { BookOpenIcon, ShieldCheckIcon, TrashIcon } from "@heroicons/react/20/solid";
 import { ShieldExclamationIcon } from "@heroicons/react/24/solid";
 import { DialogClose } from "@radix-ui/react-dialog";
@@ -168,9 +168,9 @@ const CreateTokenSchema = z.discriminatedUnion("action", [
   z.object({
     action: z.literal("create"),
     tokenName: z
-      .string({ required_error: "You must enter a name" })
+      .string({ error: "You must enter a name" })
       .min(2, "Your name must be at least 2 characters long")
-      .max(50),
+      .max(50, "Your name must be 50 characters or less"),
     // Optional — when no RBAC plugin is installed the UI hides the
     // dropdown and submits no roleId; the action passes that through
     // and createPersonalAccessToken just doesn't write a TokenRole.
diff --git a/apps/webapp/app/routes/admin.feature-flags.tsx b/apps/webapp/app/routes/admin.feature-flags.tsx
index 76ba62ff8e9..f26c85520a9 100644
--- a/apps/webapp/app/routes/admin.feature-flags.tsx
+++ b/apps/webapp/app/routes/admin.feature-flags.tsx
@@ -87,7 +87,7 @@ export const action = dashboardAction(
       return json({ error: "Invalid JSON body" }, { status: 400 });
     }
 
-    const payloadSchema = z.object({ flags: z.record(z.unknown()) });
+    const payloadSchema = z.object({ flags: z.record(z.string(), z.unknown()) });
     const parsed = payloadSchema.safeParse(body);
     if (!parsed.success) {
       return json({ error: "Invalid payload" }, { status: 400 });
diff --git a/apps/webapp/app/routes/api.v1.plain.customer-cards.ts b/apps/webapp/app/routes/api.v1.plain.customer-cards.ts
index 5e09fb08544..ea7c3abf123 100644
--- a/apps/webapp/app/routes/api.v1.plain.customer-cards.ts
+++ b/apps/webapp/app/routes/api.v1.plain.customer-cards.ts
@@ -106,7 +106,7 @@ export async function action({ request }: ActionFunctionArgs) {
 
   if (!parsed.success) {
     logger.warn("Invalid Plain customer card request", {
-      errors: parsed.error.errors,
+      errors: parsed.error.issues,
     });
     return json({ error: "Invalid request body" }, { status: 400 });
   }
diff --git a/apps/webapp/app/routes/api.v1.prompts.$slug.ts b/apps/webapp/app/routes/api.v1.prompts.$slug.ts
index 316701581e5..68a3465c181 100644
--- a/apps/webapp/app/routes/api.v1.prompts.$slug.ts
+++ b/apps/webapp/app/routes/api.v1.prompts.$slug.ts
@@ -95,7 +95,7 @@ export const loader = createLoaderApiRoute(
 // POST /api/v1/prompts/:slug — Resolve prompt with variables
 
 const ResolveBody = z.object({
-  variables: z.record(z.unknown()).default({}),
+  variables: z.record(z.string(), z.unknown()).default({}),
   label: z.string().optional(),
   version: z.number().optional(),
 });
diff --git a/apps/webapp/app/routes/api.v1.query.ts b/apps/webapp/app/routes/api.v1.query.ts
index 2f4011455ba..f08b9dd1583 100644
--- a/apps/webapp/app/routes/api.v1.query.ts
+++ b/apps/webapp/app/routes/api.v1.query.ts
@@ -93,7 +93,7 @@ const { action, loader } = createActionApiRoute(
     const { result, periodClipped: _periodClipped, maxQueryPeriod: _maxQueryPeriod } = queryResult;
 
     if (format === "csv") {
-      const csv = rowsToCSV(result.rows, result.columns);
+      const csv = rowsToCSV(result.rows as Record<string, unknown>[], result.columns);
 
       return json({
         format: "csv",
diff --git a/apps/webapp/app/routes/api.v1.schedules.ts b/apps/webapp/app/routes/api.v1.schedules.ts
index b5fd2fd968c..c7eb6f87281 100644
--- a/apps/webapp/app/routes/api.v1.schedules.ts
+++ b/apps/webapp/app/routes/api.v1.schedules.ts
@@ -108,6 +108,7 @@ export async function loader({ request }: LoaderFunctionArgs) {
     environmentId: authenticationResult.environment.id,
     page: params.data.page ?? 1,
     pageSize: params.data.perPage,
+    tasks: undefined,
   });
 
   return {
diff --git a/apps/webapp/app/routes/confirm-basic-details.tsx b/apps/webapp/app/routes/confirm-basic-details.tsx
index 4e370913240..efea8ac4ad0 100644
--- a/apps/webapp/app/routes/confirm-basic-details.tsx
+++ b/apps/webapp/app/routes/confirm-basic-details.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, getInputProps, useForm } from "@conform-to/react";
-import { conformZodMessage, parseWithZod } from "@conform-to/zod";
+import { conformZodMessage, parseWithZod } from "@conform-to/zod/v4";
 import { ArrowRightIcon, EnvelopeIcon, UserIcon } from "@heroicons/react/20/solid";
 import { HandRaisedIcon } from "@heroicons/react/24/solid";
 import { RadioGroup } from "@radix-ui/react-radio-group";
@@ -316,7 +316,10 @@ export default function Page() {
                 </InputGroup>
               ) : (
                 <>
-                  <input {...getInputProps(confirmEmail, { type: "hidden" })} value={user.email} />
+                  <input
+                    {...getInputProps(confirmEmail, { type: "hidden", value: false })}
+                    value={user.email}
+                  />
                 </>
               )}
 
diff --git a/apps/webapp/app/routes/invite-resend.tsx b/apps/webapp/app/routes/invite-resend.tsx
index 3cba88bd20a..d64cc2d2aaf 100644
--- a/apps/webapp/app/routes/invite-resend.tsx
+++ b/apps/webapp/app/routes/invite-resend.tsx
@@ -1,4 +1,4 @@
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { json } from "@remix-run/server-runtime";
 import { env } from "process";
 import { z } from "zod";
diff --git a/apps/webapp/app/routes/invite-revoke.tsx b/apps/webapp/app/routes/invite-revoke.tsx
index fc1e4d0b79e..d4ab69f9c83 100644
--- a/apps/webapp/app/routes/invite-revoke.tsx
+++ b/apps/webapp/app/routes/invite-revoke.tsx
@@ -1,4 +1,4 @@
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { json } from "@remix-run/server-runtime";
 import { z } from "zod";
 import { $replica } from "~/db.server";
diff --git a/apps/webapp/app/routes/invites.tsx b/apps/webapp/app/routes/invites.tsx
index 6cf667c8677..acc0a09f4a3 100644
--- a/apps/webapp/app/routes/invites.tsx
+++ b/apps/webapp/app/routes/invites.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, useForm } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { EnvelopeIcon } from "@heroicons/react/20/solid";
 import { type ActionFunction, type LoaderFunctionArgs, json, redirect } from "@remix-run/node";
 import { Form, useActionData } from "@remix-run/react";
diff --git a/apps/webapp/app/routes/login._index/route.tsx b/apps/webapp/app/routes/login._index/route.tsx
index ce186c73461..a3d402078e8 100644
--- a/apps/webapp/app/routes/login._index/route.tsx
+++ b/apps/webapp/app/routes/login._index/route.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, getInputProps, useForm } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { EnvelopeIcon, LockClosedIcon } from "@heroicons/react/20/solid";
 import type { LoaderFunctionArgs, MetaFunction } from "@remix-run/node";
 import { Form, useNavigation } from "@remix-run/react";
@@ -38,9 +38,7 @@ import { cn } from "~/utils/cn";
 // format validation in the browser and renders the styled inline error.
 // Server-side errors still surface via the session-backed authError below.
 const emailSchema = z.object({
-  email: z
-    .string({ required_error: "Enter your email address" })
-    .email("Enter a valid email address"),
+  email: z.string({ error: "Enter your email address" }).email("Enter a valid email address"),
 });
 
 function LastUsedBadge({ className }: { className?: string }) {
diff --git a/apps/webapp/app/routes/login.sso/route.tsx b/apps/webapp/app/routes/login.sso/route.tsx
index 1ed85497353..f3c3b0a4188 100644
--- a/apps/webapp/app/routes/login.sso/route.tsx
+++ b/apps/webapp/app/routes/login.sso/route.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, getInputProps, useForm } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { ArrowLeftIcon, ArrowUpRightIcon } from "@heroicons/react/20/solid";
 import type { LoaderFunctionArgs, MetaFunction } from "@remix-run/node";
 import { Form, useNavigation } from "@remix-run/react";
@@ -67,7 +67,7 @@ const ERROR_MESSAGES: Record<string, string> = {
 // inline error before submit. Server-side errors keep flowing via ?error=.
 const ssoEmailSchema = z.object({
   email: z
-    .string({ required_error: "Enter your enterprise email address" })
+    .string({ error: "Enter your enterprise email address" })
     .email("Enter a valid email address"),
 });
 
diff --git a/apps/webapp/app/routes/resources.$projectId.deployments.$deploymentShortCode.cancel.ts b/apps/webapp/app/routes/resources.$projectId.deployments.$deploymentShortCode.cancel.ts
index 239d0982f9e..6acf14777c0 100644
--- a/apps/webapp/app/routes/resources.$projectId.deployments.$deploymentShortCode.cancel.ts
+++ b/apps/webapp/app/routes/resources.$projectId.deployments.$deploymentShortCode.cancel.ts
@@ -1,4 +1,4 @@
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { json } from "@remix-run/node";
 import { errAsync, fromPromise, okAsync } from "neverthrow";
 import { z } from "zod";
diff --git a/apps/webapp/app/routes/resources.$projectId.deployments.$deploymentShortCode.promote.ts b/apps/webapp/app/routes/resources.$projectId.deployments.$deploymentShortCode.promote.ts
index 979264516d1..529f627e5fb 100644
--- a/apps/webapp/app/routes/resources.$projectId.deployments.$deploymentShortCode.promote.ts
+++ b/apps/webapp/app/routes/resources.$projectId.deployments.$deploymentShortCode.promote.ts
@@ -1,4 +1,4 @@
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { json } from "@remix-run/node";
 import { z } from "zod";
 import { $replica, prisma } from "~/db.server";
diff --git a/apps/webapp/app/routes/resources.$projectId.deployments.$deploymentShortCode.rollback.ts b/apps/webapp/app/routes/resources.$projectId.deployments.$deploymentShortCode.rollback.ts
index d109e97c9d5..3caed9013b3 100644
--- a/apps/webapp/app/routes/resources.$projectId.deployments.$deploymentShortCode.rollback.ts
+++ b/apps/webapp/app/routes/resources.$projectId.deployments.$deploymentShortCode.rollback.ts
@@ -1,4 +1,4 @@
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { json } from "@remix-run/node";
 import { z } from "zod";
 import { $replica, prisma } from "~/db.server";
diff --git a/apps/webapp/app/routes/resources.batches.$batchId.check-completion.ts b/apps/webapp/app/routes/resources.batches.$batchId.check-completion.ts
index 2d1c6bc702b..3c7cd64523b 100644
--- a/apps/webapp/app/routes/resources.batches.$batchId.check-completion.ts
+++ b/apps/webapp/app/routes/resources.batches.$batchId.check-completion.ts
@@ -1,4 +1,4 @@
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import type { ActionFunction } from "@remix-run/node";
 import { json } from "@remix-run/node";
 import { z } from "zod";
diff --git a/apps/webapp/app/routes/resources.branches.archive.tsx b/apps/webapp/app/routes/resources.branches.archive.tsx
index bf9e05a0d64..dfc542f793f 100644
--- a/apps/webapp/app/routes/resources.branches.archive.tsx
+++ b/apps/webapp/app/routes/resources.branches.archive.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, getInputProps, useForm } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { DialogClose } from "@radix-ui/react-dialog";
 import { Form, useActionData, useLocation } from "@remix-run/react";
 import { type ActionFunctionArgs } from "@remix-run/server-runtime";
@@ -100,10 +100,13 @@ export function ArchiveButton({
             {...getFormProps(form)}
             className="w-full"
           >
-            <input value={environment.id} {...getInputProps(environmentId, { type: "hidden" })} />
+            <input
+              value={environment.id}
+              {...getInputProps(environmentId, { type: "hidden", value: false })}
+            />
             <input
               value={`${location.pathname}${location.search}`}
-              {...getInputProps(redirectPath, { type: "hidden" })}
+              {...getInputProps(redirectPath, { type: "hidden", value: false })}
             />
             <Paragraph spacing>
               This will <span className="text-text-bright">permanently</span> make this branch{" "}
@@ -116,7 +119,7 @@ export function ArchiveButton({
             <Paragraph spacing>
               Once archived you can create a new branch with the same name.
             </Paragraph>
-            <FormError>{form.errors}</FormError>
+            <FormError>{form.errors?.join(", ")}</FormError>
             <FormButtons
               confirmButton={
                 <Button LeadingIcon={ArchiveIcon} type="submit" variant="danger/medium">
diff --git a/apps/webapp/app/routes/resources.branches.create.tsx b/apps/webapp/app/routes/resources.branches.create.tsx
index 9fa5aaeace8..23a8b822d19 100644
--- a/apps/webapp/app/routes/resources.branches.create.tsx
+++ b/apps/webapp/app/routes/resources.branches.create.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, getInputProps, useForm } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { DialogClose } from "@radix-ui/react-dialog";
 import { useFetcher, useLocation, useSearchParams } from "@remix-run/react";
 import { type ActionFunctionArgs, json } from "@remix-run/server-runtime";
diff --git a/apps/webapp/app/routes/resources.feedback.ts b/apps/webapp/app/routes/resources.feedback.ts
index 4ace262f0cb..41f0f24249d 100644
--- a/apps/webapp/app/routes/resources.feedback.ts
+++ b/apps/webapp/app/routes/resources.feedback.ts
@@ -1,4 +1,4 @@
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { type ActionFunctionArgs, json } from "@remix-run/server-runtime";
 import { uiComponent } from "@team-plain/ui-components";
 import { z } from "zod";
@@ -56,8 +56,7 @@ const feedbackTypeLiterals = Object.keys(feedbackTypes).map((key) => z.literal(k
 const feedbackType = z.union(
   [feedbackTypeLiterals[0], feedbackTypeLiterals[1], ...feedbackTypeLiterals.slice(2)],
   {
-    required_error: "Must be either 'bug' or 'feature'",
-    invalid_type_error: "Must be either 'bug' or 'feature'",
+    error: "Must be a valid feedback type",
   }
 );
 
diff --git a/apps/webapp/app/routes/resources.orgs.$organizationSlug.projects.$projectParam.env.$envParam.github.tsx b/apps/webapp/app/routes/resources.orgs.$organizationSlug.projects.$projectParam.env.$envParam.github.tsx
index 4840a424d8c..e5dfd81a97e 100644
--- a/apps/webapp/app/routes/resources.orgs.$organizationSlug.projects.$projectParam.env.$envParam.github.tsx
+++ b/apps/webapp/app/routes/resources.orgs.$organizationSlug.projects.$projectParam.env.$envParam.github.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, getInputProps, useForm } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import {
   ArrowUpCircleIcon,
   ArrowUpRightIcon,
diff --git a/apps/webapp/app/routes/resources.orgs.$organizationSlug.projects.$projectParam.env.$envParam.runs.bulkaction.tsx b/apps/webapp/app/routes/resources.orgs.$organizationSlug.projects.$projectParam.env.$envParam.runs.bulkaction.tsx
index 5bef068b994..66c5d92297a 100644
--- a/apps/webapp/app/routes/resources.orgs.$organizationSlug.projects.$projectParam.env.$envParam.runs.bulkaction.tsx
+++ b/apps/webapp/app/routes/resources.orgs.$organizationSlug.projects.$projectParam.env.$envParam.runs.bulkaction.tsx
@@ -1,4 +1,4 @@
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { ArrowPathIcon, InformationCircleIcon } from "@heroicons/react/20/solid";
 import { XCircleIcon } from "@heroicons/react/24/outline";
 import { Form } from "@remix-run/react";
diff --git a/apps/webapp/app/routes/resources.orgs.$organizationSlug.projects.$projectParam.env.$envParam.schedules.new/route.tsx b/apps/webapp/app/routes/resources.orgs.$organizationSlug.projects.$projectParam.env.$envParam.schedules.new/route.tsx
index 61ce814dbd5..32de08aca6d 100644
--- a/apps/webapp/app/routes/resources.orgs.$organizationSlug.projects.$projectParam.env.$envParam.schedules.new/route.tsx
+++ b/apps/webapp/app/routes/resources.orgs.$organizationSlug.projects.$projectParam.env.$envParam.schedules.new/route.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, getInputProps, getSelectProps, useForm } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { CheckIcon, XMarkIcon } from "@heroicons/react/20/solid";
 import {
   type FetcherWithComponents,
@@ -196,7 +196,7 @@ export function UpsertScheduleForm({
     if (!result.success) {
       cronPatternResult = {
         isValid: false,
-        error: result.error.errors[0].message,
+        error: result.error.issues[0].message,
       };
     } else {
       try {
diff --git a/apps/webapp/app/routes/resources.orgs.$organizationSlug.projects.$projectParam.env.$envParam.vercel.tsx b/apps/webapp/app/routes/resources.orgs.$organizationSlug.projects.$projectParam.env.$envParam.vercel.tsx
index 792275a917d..019a28db063 100644
--- a/apps/webapp/app/routes/resources.orgs.$organizationSlug.projects.$projectParam.env.$envParam.vercel.tsx
+++ b/apps/webapp/app/routes/resources.orgs.$organizationSlug.projects.$projectParam.env.$envParam.vercel.tsx
@@ -1,5 +1,5 @@
 import { getFormProps, useForm } from "@conform-to/react";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { CheckCircleIcon, ExclamationTriangleIcon } from "@heroicons/react/20/solid";
 import { DialogClose } from "@radix-ui/react-dialog";
 import { Form, useActionData, useFetcher, useLocation, useNavigation } from "@remix-run/react";
diff --git a/apps/webapp/app/routes/resources.orgs.$organizationSlug.projects.$projectParam.env.$envParam.waitpoints.$waitpointFriendlyId.complete/route.tsx b/apps/webapp/app/routes/resources.orgs.$organizationSlug.projects.$projectParam.env.$envParam.waitpoints.$waitpointFriendlyId.complete/route.tsx
index e1ed1b2cc70..cf3940fdfe5 100644
--- a/apps/webapp/app/routes/resources.orgs.$organizationSlug.projects.$projectParam.env.$envParam.waitpoints.$waitpointFriendlyId.complete/route.tsx
+++ b/apps/webapp/app/routes/resources.orgs.$organizationSlug.projects.$projectParam.env.$envParam.waitpoints.$waitpointFriendlyId.complete/route.tsx
@@ -1,4 +1,4 @@
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { Form, useLocation, useNavigation, useSubmit } from "@remix-run/react";
 import { type ActionFunctionArgs, json } from "@remix-run/server-runtime";
 import type { WaitpointTokenStatus } from "@trigger.dev/core/v3";
diff --git a/apps/webapp/app/routes/resources.orgs.$organizationSlug.schedules-addon.ts b/apps/webapp/app/routes/resources.orgs.$organizationSlug.schedules-addon.ts
index d61bea07045..88f27b4d47c 100644
--- a/apps/webapp/app/routes/resources.orgs.$organizationSlug.schedules-addon.ts
+++ b/apps/webapp/app/routes/resources.orgs.$organizationSlug.schedules-addon.ts
@@ -1,4 +1,4 @@
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { type ActionFunctionArgs, json } from "@remix-run/server-runtime";
 import { tryCatch } from "@trigger.dev/core/v3";
 import { z } from "zod";
diff --git a/apps/webapp/app/routes/resources.sessions.$sessionParam.close.ts b/apps/webapp/app/routes/resources.sessions.$sessionParam.close.ts
index 26f573399c9..b0f820fccc7 100644
--- a/apps/webapp/app/routes/resources.sessions.$sessionParam.close.ts
+++ b/apps/webapp/app/routes/resources.sessions.$sessionParam.close.ts
@@ -1,4 +1,4 @@
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { type ActionFunction, json } from "@remix-run/node";
 import { z } from "zod";
 import { $replica, prisma } from "~/db.server";
diff --git a/apps/webapp/app/routes/resources.taskruns.$runParam.cancel.ts b/apps/webapp/app/routes/resources.taskruns.$runParam.cancel.ts
index cf6b0317780..7610f2c099c 100644
--- a/apps/webapp/app/routes/resources.taskruns.$runParam.cancel.ts
+++ b/apps/webapp/app/routes/resources.taskruns.$runParam.cancel.ts
@@ -1,4 +1,4 @@
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { json } from "@remix-run/node";
 import { z } from "zod";
 import { prisma } from "~/db.server";
diff --git a/apps/webapp/app/routes/resources.taskruns.$runParam.replay.ts b/apps/webapp/app/routes/resources.taskruns.$runParam.replay.ts
index e91ac2c5451..73e45b94d5d 100644
--- a/apps/webapp/app/routes/resources.taskruns.$runParam.replay.ts
+++ b/apps/webapp/app/routes/resources.taskruns.$runParam.replay.ts
@@ -1,4 +1,4 @@
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { json, type LoaderFunctionArgs } from "@remix-run/node";
 import { type EnvironmentType, prettyPrintPacket } from "@trigger.dev/core/v3";
 import { type Prisma } from "@trigger.dev/database";
diff --git a/apps/webapp/app/services/apiAuth.server.ts b/apps/webapp/app/services/apiAuth.server.ts
index 90fc9d2d3b7..8f2d4abad8e 100644
--- a/apps/webapp/app/services/apiAuth.server.ts
+++ b/apps/webapp/app/services/apiAuth.server.ts
@@ -768,7 +768,7 @@ export async function validateJWTTokenAndRenew<T extends z.ZodTypeAny>(
       return;
     }
 
-    const renewedJwt = await renewJWTToken(payload.data);
+    const renewedJwt = await renewJWTToken(payload.data as Record<string, string>);
 
     return {
       payload: payload.data,
@@ -807,7 +807,7 @@ export async function validateJWTTokenAndRenew<T extends z.ZodTypeAny>(
       }
 
       const renewedJwt = await generateJWTTokenForEnvironment(authenticatedEnv.environment, {
-        ...payload.data,
+        ...(payload.data as Record<string, string>),
       });
 
       // The environment carries secret material; log only non-secret fields.
diff --git a/apps/webapp/app/services/authorizationRateLimitMiddleware.server.ts b/apps/webapp/app/services/authorizationRateLimitMiddleware.server.ts
index 5fcd6eb5450..349c8cf0d7e 100644
--- a/apps/webapp/app/services/authorizationRateLimitMiddleware.server.ts
+++ b/apps/webapp/app/services/authorizationRateLimitMiddleware.server.ts
@@ -118,7 +118,7 @@ async function resolveLimitConfig(
     if (!parsedOverride.success) {
       logger.error("Error parsing rate limiter override", {
         override,
-        errors: parsedOverride.error.errors,
+        errors: parsedOverride.error.issues,
       });
 
       return defaultLimiter;
diff --git a/apps/webapp/app/services/billingLimit.schemas.ts b/apps/webapp/app/services/billingLimit.schemas.ts
index 6628e5cb22c..8ffdca3fd57 100644
--- a/apps/webapp/app/services/billingLimit.schemas.ts
+++ b/apps/webapp/app/services/billingLimit.schemas.ts
@@ -1,4 +1,3 @@
-import type { BillingClient } from "@trigger.dev/platform";
 import { z } from "zod";
 
 /**
@@ -175,7 +174,7 @@ export type BillingLimitPageData = BillingLimitResult & {
   currentSpendCents: number;
 };
 
-/** Bridge webapp Zod schemas to BillingClient.fetch (separate Zod type instances). */
-export function asPlatformSchema(schema: z.ZodTypeAny) {
-  return schema as unknown as Parameters<BillingClient["fetch"]>[1];
+/** Preserve a concrete schema type when passing it to BillingClient.fetch. */
+export function asPlatformSchema<TSchema extends z.ZodType>(schema: TSchema): TSchema {
+  return schema;
 }
diff --git a/apps/webapp/app/services/platform.v3.server.ts b/apps/webapp/app/services/platform.v3.server.ts
index f8b524e3cdd..a533cafaf42 100644
--- a/apps/webapp/app/services/platform.v3.server.ts
+++ b/apps/webapp/app/services/platform.v3.server.ts
@@ -242,7 +242,7 @@ const MachineOverrideValues = z.object({
 });
 type MachineOverrideValues = z.infer<typeof MachineOverrideValues>;
 
-const MachineOverrides = z.record(MachinePresetName, MachineOverrideValues.partial());
+const MachineOverrides = z.partialRecord(MachinePresetName, MachineOverrideValues.partial());
 type MachineOverrides = z.infer<typeof MachineOverrides>;
 
 const MachinePresetOverrides = z.object({
diff --git a/apps/webapp/app/services/queryService.server.ts b/apps/webapp/app/services/queryService.server.ts
index 755da8ec3a3..77f2b3f4178 100644
--- a/apps/webapp/app/services/queryService.server.ts
+++ b/apps/webapp/app/services/queryService.server.ts
@@ -381,7 +381,7 @@ export async function executeQuery<TOut extends z.ZodSchema>(
 
     const result = await executeTSQL(queryClickhouse.reader, {
       ...baseOptions,
-      schema: z.record(z.any()),
+      schema: z.record(z.string(), z.any()) as unknown as TOut,
       tableSchema: effectiveSchemas,
       transformValues: true,
       enforcedWhereClause,
diff --git a/apps/webapp/app/services/routeBuilders/apiBuilder.server.ts b/apps/webapp/app/services/routeBuilders/apiBuilder.server.ts
index 83212a6e8b2..fe01c3504e6 100644
--- a/apps/webapp/app/services/routeBuilders/apiBuilder.server.ts
+++ b/apps/webapp/app/services/routeBuilders/apiBuilder.server.ts
@@ -127,7 +127,7 @@ async function rejectRestrictedKeyWithoutAuthorization({
   );
 }
 
-type AnyZodSchema = z.ZodFirstPartySchemaTypes | z.ZodDiscriminatedUnion<any, any>;
+type AnyZodSchema = z.ZodType;
 
 // A multi-resource auth check has two possible directions, and route authors
 // have to pick one explicitly:
diff --git a/apps/webapp/app/services/routeBuilders/dashboardBuilder.server.ts b/apps/webapp/app/services/routeBuilders/dashboardBuilder.server.ts
index 01bdb6d9b53..42d8acd4bf2 100644
--- a/apps/webapp/app/services/routeBuilders/dashboardBuilder.server.ts
+++ b/apps/webapp/app/services/routeBuilders/dashboardBuilder.server.ts
@@ -12,7 +12,7 @@ import type { AuthorizationOption, DashboardLoaderOptions, SessionUser } from ".
 import { fromZodError } from "zod-validation-error";
 import type { z } from "zod";
 
-type AnyZodSchema = z.ZodFirstPartySchemaTypes | z.ZodDiscriminatedUnion<any, any>;
+type AnyZodSchema = z.ZodType;
 
 function loginRedirectFor(request: Request, override?: string): Response {
   if (override) return redirect(override);
diff --git a/apps/webapp/app/services/routeBuilders/dashboardBuilder.ts b/apps/webapp/app/services/routeBuilders/dashboardBuilder.ts
index a4603895915..b2b8d72f10b 100644
--- a/apps/webapp/app/services/routeBuilders/dashboardBuilder.ts
+++ b/apps/webapp/app/services/routeBuilders/dashboardBuilder.ts
@@ -17,7 +17,7 @@ import type { ActionFunctionArgs, LoaderFunctionArgs } from "@remix-run/server-r
 import type { RbacAbility, RbacResource } from "@trigger.dev/rbac";
 import type { z } from "zod";
 
-type AnyZodSchema = z.ZodFirstPartySchemaTypes | z.ZodDiscriminatedUnion<any, any>;
+type AnyZodSchema = z.ZodType;
 
 type InferZod<T> = T extends z.ZodFirstPartySchemaTypes | z.ZodDiscriminatedUnion<any, any>
   ? z.infer<T>
diff --git a/apps/webapp/app/utils/json.ts b/apps/webapp/app/utils/json.ts
index b3b44055958..e32960a08af 100644
--- a/apps/webapp/app/utils/json.ts
+++ b/apps/webapp/app/utils/json.ts
@@ -15,7 +15,7 @@ export function safeJsonParse(json?: string): unknown {
 export function safeJsonZodParse<T>(
   schema: z.Schema<T>,
   json: string
-): z.SafeParseReturnType<unknown, T> | undefined {
+): z.ZodSafeParseResult<T> | undefined {
   const parsed = safeJsonParse(json);
 
   if (parsed === null) {
@@ -51,7 +51,7 @@ export async function safeBodyFromResponse<T>(
 export async function safeParseBodyFromResponse<T>(
   response: Response,
   schema: z.Schema<T>
-): Promise<z.SafeParseReturnType<unknown, T> | undefined> {
+): Promise<z.ZodSafeParseResult<T> | undefined> {
   try {
     const unknownJson = await response.json();
 
diff --git a/apps/webapp/app/utils/timeGranularity.ts b/apps/webapp/app/utils/timeGranularity.ts
index 0c8ecc41ac8..4e4d542de3a 100644
--- a/apps/webapp/app/utils/timeGranularity.ts
+++ b/apps/webapp/app/utils/timeGranularity.ts
@@ -6,7 +6,7 @@ const DurationString = z.string().refine(
     const ms = parseDuration(val);
     return ms !== null && ms > 0;
   },
-  (val) => ({ message: `Invalid or non-positive duration string: "${val}"` })
+  { error: (issue) => `Invalid or non-positive duration string: "${issue.input}"` }
 );
 
 const BracketSchema = z.object({
diff --git a/apps/webapp/app/v3/featureFlags.server.ts b/apps/webapp/app/v3/featureFlags.server.ts
index c79bd8c01d7..1a435a48e52 100644
--- a/apps/webapp/app/v3/featureFlags.server.ts
+++ b/apps/webapp/app/v3/featureFlags.server.ts
@@ -37,7 +37,7 @@ export function makeFlag(_prisma: PrismaClientOrTransaction = prisma) {
       const parsed = flagSchema.safeParse(opts.overrides[opts.key]);
 
       if (parsed.success) {
-        return parsed.data;
+        return parsed.data as z.infer<(typeof FeatureFlagCatalog)[T]>;
       }
     }
 
@@ -45,7 +45,7 @@ export function makeFlag(_prisma: PrismaClientOrTransaction = prisma) {
       const parsed = flagSchema.safeParse(value.value);
 
       if (parsed.success) {
-        return parsed.data;
+        return parsed.data as z.infer<(typeof FeatureFlagCatalog)[T]>;
       }
     }
 
diff --git a/apps/webapp/app/v3/featureFlags.ts b/apps/webapp/app/v3/featureFlags.ts
index f617cab16f3..d6ba1fb191f 100644
--- a/apps/webapp/app/v3/featureFlags.ts
+++ b/apps/webapp/app/v3/featureFlags.ts
@@ -112,8 +112,10 @@ export type FeatureFlagCatalog = z.infer<typeof FeatureFlagCatalogSchema>;
 export function validateFeatureFlagValue<T extends FeatureFlagKey>(
   key: T,
   value: unknown
-): z.SafeParseReturnType<unknown, z.infer<(typeof FeatureFlagCatalog)[T]>> {
-  return FeatureFlagCatalog[key].safeParse(value);
+): ReturnType<(typeof FeatureFlagCatalog)[T]["safeParse"]> {
+  return FeatureFlagCatalog[key].safeParse(value) as ReturnType<
+    (typeof FeatureFlagCatalog)[T]["safeParse"]
+  >;
 }
 
 // Utility function to validate all feature flags at once
@@ -162,23 +164,28 @@ export type FlagControlType =
   | { type: "number"; min?: number; max?: number }
   | { type: "string" };
 
-export function getFlagControlType(schema: z.ZodTypeAny): FlagControlType {
-  const typeName = schema._def.typeName;
+export function getFlagControlType(schema: z.ZodType): FlagControlType {
+  // zod v4: schema.def.type is a lowercase tag ("boolean"/"enum"/"number"/...).
+  const def = schema.def as {
+    type: string;
+    checks?: Array<{ _zod?: { def?: { check?: string; value?: number } } }>;
+  };
 
-  if (typeName === "ZodBoolean") {
+  if (def.type === "boolean") {
     return { type: "boolean" };
   }
 
-  if (typeName === "ZodEnum") {
-    return { type: "enum", options: schema._def.values as string[] };
+  if (def.type === "enum") {
+    return { type: "enum", options: (schema as z.ZodEnum).options as string[] };
   }
 
-  // z.coerce.number() reports as ZodNumber; pull min/max out of its checks
-  // so the UI can render a constrained number input instead of free text.
-  if (typeName === "ZodNumber") {
-    const checks = (schema._def.checks ?? []) as Array<{ kind: string; value?: number }>;
-    const min = checks.find((c) => c.kind === "min")?.value;
-    const max = checks.find((c) => c.kind === "max")?.value;
+  // z.coerce.number() reports as "number"; pull min/max out of its v4 checks
+  // (each check carries `_zod.def.{check,value}`) so the UI can render a
+  // constrained number input instead of free text.
+  if (def.type === "number") {
+    const checks = def.checks ?? [];
+    const min = checks.find((c) => c._zod?.def?.check === "greater_than")?._zod?.def?.value;
+    const max = checks.find((c) => c._zod?.def?.check === "less_than")?._zod?.def?.value;
     return { type: "number", min, max };
   }
 
diff --git a/apps/webapp/app/v3/schedules.ts b/apps/webapp/app/v3/schedules.ts
index 1653e053544..e0d33c77654 100644
--- a/apps/webapp/app/v3/schedules.ts
+++ b/apps/webapp/app/v3/schedules.ts
@@ -20,28 +20,25 @@ export const CronPattern = z.string().refine(
       return false;
     }
   },
-  (val) => {
-    const parts = val.split(" ");
-    if (parts.length > 5) {
-      return {
-        message: "CRON expressions with seconds are not allowed",
-      };
-    }
+  {
+    error: (issue) => {
+      const val = String(issue.input);
+      const parts = val.split(" ");
+      if (parts.length > 5) {
+        return "CRON expressions with seconds are not allowed";
+      }
 
-    if (val === "") {
-      return {
-        message: "CRON expression is required",
-      };
-    }
+      if (val === "") {
+        return "CRON expression is required";
+      }
 
-    try {
-      parseExpression(val);
-      return {
-        message: "Unknown problem",
-      };
-    } catch (e) {
-      return { message: e instanceof Error ? e.message : JSON.stringify(e) };
-    }
+      try {
+        parseExpression(val);
+        return "Unknown problem";
+      } catch (e) {
+        return e instanceof Error ? e.message : JSON.stringify(e);
+      }
+    },
   }
 );
 
diff --git a/apps/webapp/app/v3/services/aiRunFilterService.server.ts b/apps/webapp/app/v3/services/aiRunFilterService.server.ts
index 96b74ab3314..c3bc2b10e8b 100644
--- a/apps/webapp/app/v3/services/aiRunFilterService.server.ts
+++ b/apps/webapp/app/v3/services/aiRunFilterService.server.ts
@@ -258,7 +258,7 @@ export class AIRunFilterService {
       const validationResult = AIFilters.safeParse(output.filters);
       if (!validationResult.success) {
         logger.error("AI filter validation failed", {
-          errors: validationResult.error.errors,
+          errors: validationResult.error.issues,
           filters: output.filters,
         });
 
diff --git a/apps/webapp/app/v3/services/replayTaskRun.server.ts b/apps/webapp/app/v3/services/replayTaskRun.server.ts
index d626ec2ae8c..8e71026252c 100644
--- a/apps/webapp/app/v3/services/replayTaskRun.server.ts
+++ b/apps/webapp/app/v3/services/replayTaskRun.server.ts
@@ -20,7 +20,9 @@ type OverrideOptions = {
   metadata?: unknown;
   bulkActionId?: string;
   triggerSource?: string;
-} & RunOptionsData;
+  // zod v4 types `.optional().transform()` fields as required-with-undefined in the
+  // output; Partial keeps them omittable for callers passing a subset of overrides.
+} & Partial<RunOptionsData>;
 
 export class ReplayTaskRunService extends BaseService {
   public async call(existingTaskRun: TaskRun, overrideOptions: OverrideOptions = {}) {
diff --git a/apps/webapp/app/v3/utils/zodPubSub.server.ts b/apps/webapp/app/v3/utils/zodPubSub.server.ts
index c473443d169..6b1132a8715 100644
--- a/apps/webapp/app/v3/utils/zodPubSub.server.ts
+++ b/apps/webapp/app/v3/utils/zodPubSub.server.ts
@@ -54,7 +54,7 @@ class RedisZodSubscriber<
     eventName: K,
     listener: (payload: z.infer<TMessageCatalog[K]>) => Promise<void>
   ): void {
-    this._listeners.set(eventName as string, listener);
+    this._listeners.set(eventName as string, listener as Parameters<typeof this._listeners.set>[1]);
   }
 
   public async stopListening(): Promise<void> {
diff --git a/apps/webapp/app/v3/vercel/vercelProjectIntegrationSchema.ts b/apps/webapp/app/v3/vercel/vercelProjectIntegrationSchema.ts
index 1399b87fc2b..cb55583c518 100644
--- a/apps/webapp/app/v3/vercel/vercelProjectIntegrationSchema.ts
+++ b/apps/webapp/app/v3/vercel/vercelProjectIntegrationSchema.ts
@@ -71,7 +71,7 @@ export type TriggerEnvironmentType = z.infer<typeof TriggerEnvironmentType>;
  * Only explicitly `false` entries disable sync.
  */
 export const SyncEnvVarsMappingSchema = z
-  .record(EnvSlugSchema, z.record(z.string(), z.boolean()))
+  .partialRecord(EnvSlugSchema, z.record(z.string(), z.boolean()))
   .default({});
 
 export type SyncEnvVarsMapping = z.infer<typeof SyncEnvVarsMappingSchema>;
diff --git a/apps/webapp/package.json b/apps/webapp/package.json
index 90dc46ac088..0a43858a722 100644
--- a/apps/webapp/package.json
+++ b/apps/webapp/package.json
@@ -120,7 +120,7 @@
     "@trigger.dev/core": "workspace:*",
     "@trigger.dev/database": "workspace:*",
     "@trigger.dev/otlp-importer": "workspace:*",
-    "@trigger.dev/platform": "1.3.0",
+    "@trigger.dev/platform": "1.3.1",
     "@trigger.dev/plugins": "workspace:*",
     "@trigger.dev/rbac": "workspace:*",
     "@trigger.dev/redis-worker": "workspace:*",
@@ -216,9 +216,9 @@
     "util": "^0.12.5",
     "uuid": "^14.0.0",
     "ws": "^8.11.0",
-    "zod": "3.25.76",
-    "zod-error": "1.5.0",
-    "zod-validation-error": "^1.5.0"
+    "zod": "4.4.3",
+    "zod-error": "2.0.0",
+    "zod-validation-error": "^5.0.0"
   },
   "devDependencies": {
     "@internal/clickhouse": "workspace:*",
diff --git a/apps/webapp/test/billingLimitsRoute.test.ts b/apps/webapp/test/billingLimitsRoute.test.ts
index 66f1ac5a7b5..278ee90d791 100644
--- a/apps/webapp/test/billingLimitsRoute.test.ts
+++ b/apps/webapp/test/billingLimitsRoute.test.ts
@@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { parseWithZod } from "@conform-to/zod";
+import { parseWithZod } from "@conform-to/zod/v4";
 import { billingAlertsSchema } from "~/components/billing/BillingAlertsSection";
 import {
   billingLimitFormSchema,
diff --git a/internal-packages/clickhouse/package.json b/internal-packages/clickhouse/package.json
index ec5ec25e667..719b979ba90 100644
--- a/internal-packages/clickhouse/package.json
+++ b/internal-packages/clickhouse/package.json
@@ -10,8 +10,8 @@
     "@internal/tracing": "workspace:*",
     "@internal/tsql": "workspace:*",
     "@trigger.dev/core": "workspace:*",
-    "zod": "3.25.76",
-    "zod-error": "1.5.0"
+    "zod": "4.4.3",
+    "zod-error": "2.0.0"
   },
   "devDependencies": {
     "@internal/testcontainers": "workspace:*",
diff --git a/internal-packages/clickhouse/src/client/tsql.ts b/internal-packages/clickhouse/src/client/tsql.ts
index f61009237e4..99e6e402bc3 100644
--- a/internal-packages/clickhouse/src/client/tsql.ts
+++ b/internal-packages/clickhouse/src/client/tsql.ts
@@ -221,7 +221,7 @@ export async function executeTSQL<TOut extends z.ZodSchema>(
     const queryFn = reader.queryWithStats({
       name: isExplain ? `${options.name}-explain` : options.name,
       query: queryToExecute,
-      params: z.record(z.any()),
+      params: z.record(z.string(), z.any()),
       // EXPLAIN returns rows with an 'explain' column
       schema: isExplain ? z.object({ explain: z.string() }) : options.schema,
       settings: options.clickhouseSettings,
@@ -257,7 +257,7 @@ export async function executeTSQL<TOut extends z.ZodSchema>(
           const additionalQueryFn = reader.queryWithStats({
             name: `${options.name}-explain-${explainType.name.toLowerCase()}`,
             query: explainType.query,
-            params: z.record(z.any()),
+            params: z.record(z.string(), z.any()),
             schema: z.object({ explain: z.string() }),
             settings: options.clickhouseSettings,
             logFields: { tsql: options.query },
diff --git a/internal-packages/clickhouse/src/tsqlFunctions.test.ts b/internal-packages/clickhouse/src/tsqlFunctions.test.ts
index 8c1f9ec4221..188fd58e875 100644
--- a/internal-packages/clickhouse/src/tsqlFunctions.test.ts
+++ b/internal-packages/clickhouse/src/tsqlFunctions.test.ts
@@ -101,7 +101,7 @@ async function assertQueryExecutes(client: ClickhouseClient, tsqlQuery: string):
   const [error] = await executeTSQL(client, {
     name: "func-test",
     query: tsqlQuery,
-    schema: z.record(z.any()),
+    schema: z.record(z.string(), z.any()),
     enforcedWhereClause,
     tableSchema: [taskRunsSchema],
   });
diff --git a/internal-packages/compute/package.json b/internal-packages/compute/package.json
index 4e221879382..c5045878f54 100644
--- a/internal-packages/compute/package.json
+++ b/internal-packages/compute/package.json
@@ -14,7 +14,7 @@
     }
   },
   "dependencies": {
-    "zod": "3.25.76"
+    "zod": "4.4.3"
   },
   "devDependencies": {
     "rimraf": "6.0.1"
diff --git a/internal-packages/compute/src/types.ts b/internal-packages/compute/src/types.ts
index 5d8d5e26af9..fd878334efa 100644
--- a/internal-packages/compute/src/types.ts
+++ b/internal-packages/compute/src/types.ts
@@ -15,7 +15,7 @@ export const TemplateCreateRequestSchema = z.object({
   callback: z
     .object({
       url: z.string(),
-      metadata: z.record(z.string()).optional(),
+      metadata: z.record(z.string(), z.string()).optional(),
     })
     .optional(),
 });
@@ -38,14 +38,14 @@ export type TemplateCreateResponse = z.infer<typeof TemplateCreateResponseSchema
 export const InstanceCreateRequestSchema = z.object({
   name: z.string(),
   image: z.string(),
-  env: z.record(z.string()),
+  env: z.record(z.string(), z.string()),
   cpu: z.number(),
   memory_gb: z.number(),
-  metadata: z.record(z.unknown()).optional(),
+  metadata: z.record(z.string(), z.unknown()).optional(),
   // Per-instance identity labels; the provider promotes a configured subset
   // to network-policy selection. Distinct from metadata, which is
   // observability-only and never selected on.
-  labels: z.record(z.string()).optional(),
+  labels: z.record(z.string(), z.string()).optional(),
 });
 export type InstanceCreateRequest = z.infer<typeof InstanceCreateRequestSchema>;
 
@@ -58,7 +58,7 @@ export type InstanceCreateResponse = z.infer<typeof InstanceCreateResponseSchema
 export const InstanceSnapshotRequestSchema = z.object({
   callback: z.object({
     url: z.string(),
-    metadata: z.record(z.string()),
+    metadata: z.record(z.string(), z.string()),
   }),
 });
 export type InstanceSnapshotRequest = z.infer<typeof InstanceSnapshotRequestSchema>;
@@ -67,13 +67,13 @@ export type InstanceSnapshotRequest = z.infer<typeof InstanceSnapshotRequestSche
 
 export const SnapshotRestoreRequestSchema = z.object({
   name: z.string(),
-  metadata: z.record(z.string()),
+  metadata: z.record(z.string(), z.string()),
   cpu: z.number(),
   memory_gb: z.number(),
   // Per-instance identity labels; the caller must resupply the same set as on
   // create. The provider doesn't persist them across a snapshot, so omitting
   // them drops the restored run's policy-based network selection.
-  labels: z.record(z.string()).optional(),
+  labels: z.record(z.string(), z.string()).optional(),
 });
 export type SnapshotRestoreRequest = z.infer<typeof SnapshotRestoreRequestSchema>;
 
@@ -82,14 +82,14 @@ export const SnapshotCallbackPayloadSchema = z.discriminatedUnion("status", [
     status: z.literal("completed"),
     snapshot_id: z.string(),
     instance_id: z.string(),
-    metadata: z.record(z.string()).optional(),
+    metadata: z.record(z.string(), z.string()).optional(),
     duration_ms: z.number().optional(),
   }),
   z.object({
     status: z.literal("failed"),
     instance_id: z.string(),
     error: z.string().optional(),
-    metadata: z.record(z.string()).optional(),
+    metadata: z.record(z.string(), z.string()).optional(),
     duration_ms: z.number().optional(),
   }),
 ]);
diff --git a/internal-packages/dashboard-agent/package.json b/internal-packages/dashboard-agent/package.json
index c0776e25f11..3bfe5f3f4a6 100644
--- a/internal-packages/dashboard-agent/package.json
+++ b/internal-packages/dashboard-agent/package.json
@@ -14,7 +14,7 @@
     "@internal/dashboard-agent-db": "workspace:*",
     "@trigger.dev/sdk": "workspace:*",
     "ai": "^6.0.116",
-    "zod": "3.25.76"
+    "zod": "4.4.3"
   },
   "devDependencies": {
     "@ai-sdk/provider": "3.0.8",
diff --git a/internal-packages/emails/package.json b/internal-packages/emails/package.json
index 33dfe4c1d71..9f61faab457 100644
--- a/internal-packages/emails/package.json
+++ b/internal-packages/emails/package.json
@@ -18,7 +18,7 @@
     "react-dom": "^18.2.0",
     "resend": "^3.2.0",
     "tiny-invariant": "^1.2.0",
-    "zod": "3.25.76"
+    "zod": "4.4.3"
   },
   "devDependencies": {
     "@types/nodemailer": "^8.0.0",
diff --git a/internal-packages/run-engine/package.json b/internal-packages/run-engine/package.json
index 516e6a18696..026463ce0aa 100644
--- a/internal-packages/run-engine/package.json
+++ b/internal-packages/run-engine/package.json
@@ -32,7 +32,7 @@
     "nanoid": "3.3.8",
     "redlock": "5.0.0-beta.2",
     "seedrandom": "^3.0.5",
-    "zod": "3.25.76",
+    "zod": "4.4.3",
     "p-map": "^6.0.0"
   },
   "devDependencies": {
diff --git a/internal-packages/run-engine/src/batch-queue/types.ts b/internal-packages/run-engine/src/batch-queue/types.ts
index 9aa085e286a..0a8494abd00 100644
--- a/internal-packages/run-engine/src/batch-queue/types.ts
+++ b/internal-packages/run-engine/src/batch-queue/types.ts
@@ -37,7 +37,7 @@ export const BatchItem = z.object({
    */
   payloadType: z.string().optional(),
   /** Options for this specific item - stored as JSON */
-  options: z.record(z.unknown()).optional(),
+  options: z.record(z.string(), z.unknown()).optional(),
 });
 export type BatchItem = z.infer<typeof BatchItem>;
 
@@ -68,7 +68,7 @@ export const BatchMeta = z.object({
   /** Trigger version */
   triggerVersion: z.string().optional(),
   /** Trace context */
-  traceContext: z.record(z.unknown()).optional(),
+  traceContext: z.record(z.string(), z.unknown()).optional(),
   /** Whether span parent should be a link */
   spanParentAsLink: z.boolean().optional(),
   /** Realtime streams version */
@@ -103,7 +103,7 @@ export const BatchItemFailure = z.object({
    */
   payload: z.string().optional(),
   /** The options that were used */
-  options: z.record(z.unknown()).optional(),
+  options: z.record(z.string(), z.unknown()).optional(),
   /** Error message */
   error: z.string(),
   /** Error code if available */
diff --git a/internal-packages/schedule-engine/package.json b/internal-packages/schedule-engine/package.json
index 52a27a11e27..b8a53a75f6c 100644
--- a/internal-packages/schedule-engine/package.json
+++ b/internal-packages/schedule-engine/package.json
@@ -22,7 +22,7 @@
     "cron-parser": "^4.9.0",
     "cronstrue": "^2.50.0",
     "nanoid": "3.3.8",
-    "zod": "3.25.76"
+    "zod": "4.4.3"
   },
   "devDependencies": {
     "@internal/testcontainers": "workspace:*",
diff --git a/internal-packages/tsql/package.json b/internal-packages/tsql/package.json
index 0cac36e7b27..3c86630738f 100644
--- a/internal-packages/tsql/package.json
+++ b/internal-packages/tsql/package.json
@@ -8,7 +8,7 @@
   "dependencies": {
     "@trigger.dev/core": "workspace:*",
     "antlr4ts": "0.5.0-alpha.4",
-    "zod": "3.25.76"
+    "zod": "4.4.3"
   },
   "scripts": {
     "typecheck": "tsc --noEmit",
diff --git a/package.json b/package.json
index 2708b06be73..0718cb0178f 100644
--- a/package.json
+++ b/package.json
@@ -142,7 +142,8 @@
       "brace-expansion@>=2 <2.0.3": "2.0.3",
       "brace-expansion@>=5 <5.0.6": "5.0.6",
       "@jsonhero/json-infer-types>ip-address": "^10.2.0",
-      "@modelcontextprotocol/sdk@>=1.26.0>express-rate-limit": "^8.6.0"
+      "@modelcontextprotocol/sdk@>=1.26.0>express-rate-limit": "^8.6.0",
+      "zod": "4.4.3"
     },
     "onlyBuiltDependencies": [
       "@depot/cli",
diff --git a/packages/cli-v3/package.json b/packages/cli-v3/package.json
index 6d0d90da98f..1051d4666c8 100644
--- a/packages/cli-v3/package.json
+++ b/packages/cli-v3/package.json
@@ -146,8 +146,8 @@
     "tinyglobby": "^0.2.10",
     "ws": "^8.18.0",
     "xdg-app-paths": "^8.3.0",
-    "zod": "3.25.76",
-    "zod-validation-error": "^1.5.0"
+    "zod": "4.4.3",
+    "zod-validation-error": "^5.0.0"
   },
   "engines": {
     "node": ">=18.20.0"
diff --git a/packages/cli-v3/src/cli/common.ts b/packages/cli-v3/src/cli/common.ts
index 18d61a05803..dbb706e06c6 100644
--- a/packages/cli-v3/src/cli/common.ts
+++ b/packages/cli-v3/src/cli/common.ts
@@ -42,7 +42,7 @@ export async function handleTelemetry(action: () => Promise<void>) {
   }
 }
 
-export async function wrapCommandAction<T extends z.AnyZodObject, TResult>(
+export async function wrapCommandAction<T extends z.ZodObject<any>, TResult>(
   name: string,
   schema: T,
   options: unknown,
@@ -55,7 +55,7 @@ export async function wrapCommandAction<T extends z.AnyZodObject, TResult>(
       throw new Error(fromZodError(parsedOptions.error).toString());
     }
 
-    logger.loggerLevel = parsedOptions.data.logLevel;
+    logger.loggerLevel = parsedOptions.data.logLevel as typeof logger.loggerLevel;
 
     logger.debug(`Running "${name}" with the following options`, {
       options: options,
diff --git a/packages/cli-v3/src/commands/analyze.ts b/packages/cli-v3/src/commands/analyze.ts
index dc03d36e2e5..e52112a53bb 100644
--- a/packages/cli-v3/src/commands/analyze.ts
+++ b/packages/cli-v3/src/commands/analyze.ts
@@ -113,14 +113,14 @@ const ImportSchema = z.object({
   kind: ImportKind,
   external: z.boolean().optional(),
   original: z.string().optional(),
-  with: z.record(z.string()).optional(),
+  with: z.record(z.string(), z.string()).optional(),
 });
 
 const InputSchema = z.object({
   bytes: z.number(),
   imports: z.array(ImportSchema),
   format: z.enum(["cjs", "esm"]).optional(),
-  with: z.record(z.string()).optional(),
+  with: z.record(z.string(), z.string()).optional(),
 });
 
 const OutputImportSchema = z.object({
diff --git a/packages/cli-v3/src/mcp/tools/agentChat.ts b/packages/cli-v3/src/mcp/tools/agentChat.ts
index 992e3d436a1..3f5b390c046 100644
--- a/packages/cli-v3/src/mcp/tools/agentChat.ts
+++ b/packages/cli-v3/src/mcp/tools/agentChat.ts
@@ -70,7 +70,7 @@ const StartAgentChatInput = CommonProjectsInput.extend({
     .describe("A unique conversation ID. Reuse to resume a conversation.")
     .optional(),
   clientData: z
-    .record(z.unknown())
+    .record(z.string(), z.unknown())
     .describe("Client data to include with every message (e.g. userId, model).")
     .optional(),
   preload: z
diff --git a/packages/cli-v3/src/utilities/configFiles.ts b/packages/cli-v3/src/utilities/configFiles.ts
index 4fee41d9cc4..541a58a68ad 100644
--- a/packages/cli-v3/src/utilities/configFiles.ts
+++ b/packages/cli-v3/src/utilities/configFiles.ts
@@ -22,13 +22,13 @@ const CliConfigProfileSettings = z.object({
 });
 type CliConfigProfileSettings = z.infer<typeof CliConfigProfileSettings>;
 
-const OldCliConfigFile = z.record(CliConfigProfileSettings);
+const OldCliConfigFile = z.record(z.string(), CliConfigProfileSettings);
 type OldCliConfigFile = z.infer<typeof OldCliConfigFile>;
 
 const CliConfigFile = z.object({
   version: z.literal(2),
   currentProfile: z.string().default(DEFFAULT_PROFILE),
-  profiles: z.record(CliConfigProfileSettings),
+  profiles: z.record(z.string(), CliConfigProfileSettings),
   settings: z
     .object({
       hasSeenMCPInstallPrompt: z.boolean().optional(),
diff --git a/packages/core/package.json b/packages/core/package.json
index 292d4ff421d..7f941cf573e 100644
--- a/packages/core/package.json
+++ b/packages/core/package.json
@@ -225,9 +225,8 @@
     "std-env": "^3.8.1",
     "tinyexec": "^0.3.2",
     "uncrypto": "^0.1.3",
-    "zod": "3.25.76",
-    "zod-error": "1.5.0",
-    "zod-validation-error": "^1.5.0"
+    "zod": "^3.25.76 || ^4.0.0",
+    "zod-validation-error": "^5.0.0"
   },
   "devDependencies": {
     "@ai-sdk/provider-utils": "^1.0.22",
@@ -663,5 +662,8 @@
   "type": "module",
   "main": "./dist/commonjs/index.js",
   "types": "./dist/commonjs/index.d.ts",
-  "module": "./dist/esm/index.js"
+  "module": "./dist/esm/index.js",
+  "peerDependencies": {
+    "zod": "^3.25.76 || ^4.0.0"
+  }
 }
diff --git a/packages/core/src/schemas/eventFilter.ts b/packages/core/src/schemas/eventFilter.ts
index 66b4d645466..77aa40867ff 100644
--- a/packages/core/src/schemas/eventFilter.ts
+++ b/packages/core/src/schemas/eventFilter.ts
@@ -1,4 +1,4 @@
-import { z } from "zod";
+import { z } from "zod/v4";
 
 export const stringPatternMatchers = [
   z.object({
@@ -65,7 +65,7 @@ type EventMatcher = z.infer<typeof EventMatcherSchema>;
 export type EventFilter = { [key: string]: EventMatcher | EventFilter };
 
 export const EventFilterSchema: z.ZodType<EventFilter> = z.lazy(() =>
-  z.record(z.union([EventMatcherSchema, EventFilterSchema]))
+  z.record(z.string(), z.union([EventMatcherSchema, EventFilterSchema]))
 );
 
 export const EventRuleSchema = z.object({
diff --git a/packages/core/src/schemas/json.ts b/packages/core/src/schemas/json.ts
index 79384db156a..672eb44cc5f 100644
--- a/packages/core/src/schemas/json.ts
+++ b/packages/core/src/schemas/json.ts
@@ -1,4 +1,4 @@
-import { z } from "zod";
+import { z } from "zod/v4";
 
 const LiteralSchema = z.union([z.string(), z.number(), z.boolean(), z.null()]);
 type Literal = z.infer<typeof LiteralSchema>;
@@ -6,7 +6,11 @@ type Literal = z.infer<typeof LiteralSchema>;
 export type DeserializedJson = Literal | { [key: string]: DeserializedJson } | DeserializedJson[];
 
 export const DeserializedJsonSchema: z.ZodType<DeserializedJson> = z.lazy(() =>
-  z.union([LiteralSchema, z.array(DeserializedJsonSchema), z.record(DeserializedJsonSchema)])
+  z.union([
+    LiteralSchema,
+    z.array(DeserializedJsonSchema),
+    z.record(z.string(), DeserializedJsonSchema),
+  ])
 );
 
 const SerializableSchema = z.union([
@@ -26,5 +30,9 @@ export type SerializableJson =
   | SerializableJson[];
 
 export const SerializableJsonSchema: z.ZodType<SerializableJson> = z.lazy(() =>
-  z.union([SerializableSchema, z.array(SerializableJsonSchema), z.record(SerializableJsonSchema)])
+  z.union([
+    SerializableSchema,
+    z.array(SerializableJsonSchema),
+    z.record(z.string(), SerializableJsonSchema),
+  ])
 );
diff --git a/packages/core/src/v3/apiClient/core.ts b/packages/core/src/v3/apiClient/core.ts
index c6425e7ee37..0bdd0f01f09 100644
--- a/packages/core/src/v3/apiClient/core.ts
+++ b/packages/core/src/v3/apiClient/core.ts
@@ -1,5 +1,6 @@
-import { z } from "zod";
-import { fromZodError, ValidationError } from "zod-validation-error";
+import { z as z3 } from "zod/v3";
+import { z } from "zod/v4";
+import { fromZodError, ValidationError } from "zod-validation-error/v4";
 import type { RetryOptions } from "../schemas/index.js";
 import { calculateNextRetryDelay } from "../utils/retries.js";
 import { ApiConnectionError, ApiError, ApiSchemaValidationError } from "./errors.js";
@@ -12,6 +13,7 @@ import { SemanticInternalAttributes } from "../semanticInternalAttributes.js";
 import type { TriggerTracer } from "../tracer.js";
 import { randomUUID } from "../utils/crypto.js";
 import { accessoryAttributes } from "../utils/styleAttributes.js";
+import type { AnyZodSchema, inferZodSchemaOutput } from "../types/schemas.js";
 import type {
   CursorPageParams,
   CursorPageResponse,
@@ -71,16 +73,16 @@ interface FetchOffsetLimitPageParams extends OffsetLimitPageParams {
   query?: URLSearchParams;
 }
 
-export function zodfetch<TResponseBodySchema extends z.ZodTypeAny>(
+export function zodfetch<TResponseBodySchema extends AnyZodSchema>(
   schema: TResponseBodySchema,
   url: string,
   requestInit?: RequestInit,
-  options?: ZodFetchOptions<z.output<TResponseBodySchema>>
-): ApiPromise<z.output<TResponseBodySchema>> {
+  options?: ZodFetchOptions<inferZodSchemaOutput<TResponseBodySchema>>
+): ApiPromise<inferZodSchemaOutput<TResponseBodySchema>> {
   return new ApiPromise(_doZodFetch(schema, url, requestInit, options));
 }
 
-export function zodfetchCursorPage<TItemSchema extends z.ZodTypeAny>(
+export function zodfetchCursorPage<TItemSchema extends AnyZodSchema>(
   schema: TItemSchema,
   url: string,
   params: FetchCursorPageParams,
@@ -101,13 +103,22 @@ export function zodfetchCursorPage<TItemSchema extends z.ZodTypeAny>(
     query.set("page[before]", params.before);
   }
 
-  const cursorPageSchema = z.object({
-    data: z.array(schema),
-    pagination: z.object({
-      next: z.string().optional(),
-      previous: z.string().optional(),
-    }),
-  });
+  const cursorPageSchema =
+    "_zod" in schema
+      ? z.object({
+          data: z.array(schema as any),
+          pagination: z.object({
+            next: z.string().optional(),
+            previous: z.string().optional(),
+          }),
+        })
+      : z3.object({
+          data: z3.array(schema as any),
+          pagination: z3.object({
+            next: z3.string().optional(),
+            previous: z3.string().optional(),
+          }),
+        });
 
   const $url = new URL(url);
   $url.search = query.toString();
@@ -117,7 +128,7 @@ export function zodfetchCursorPage<TItemSchema extends z.ZodTypeAny>(
   return new CursorPagePromise(fetchResult, schema, url, params, requestInit, options);
 }
 
-export function zodfetchOffsetLimitPage<TItemSchema extends z.ZodTypeAny>(
+export function zodfetchOffsetLimitPage<TItemSchema extends AnyZodSchema>(
   schema: TItemSchema,
   url: string,
   params: FetchOffsetLimitPageParams,
@@ -134,14 +145,24 @@ export function zodfetchOffsetLimitPage<TItemSchema extends z.ZodTypeAny>(
     query.set("page", String(params.page));
   }
 
-  const offsetLimitPageSchema = z.object({
-    data: z.array(schema),
-    pagination: z.object({
-      currentPage: z.coerce.number(),
-      totalPages: z.coerce.number(),
-      count: z.coerce.number(),
-    }),
-  });
+  const offsetLimitPageSchema =
+    "_zod" in schema
+      ? z.object({
+          data: z.array(schema as any),
+          pagination: z.object({
+            currentPage: z.coerce.number(),
+            totalPages: z.coerce.number(),
+            count: z.coerce.number(),
+          }),
+        })
+      : z3.object({
+          data: z3.array(schema as any),
+          pagination: z3.object({
+            currentPage: z3.coerce.number(),
+            totalPages: z3.coerce.number(),
+            count: z3.coerce.number(),
+          }),
+        });
 
   const $url = new URL(url);
   $url.search = query.toString();
@@ -149,7 +170,9 @@ export function zodfetchOffsetLimitPage<TItemSchema extends z.ZodTypeAny>(
   const fetchResult = _doZodFetch(offsetLimitPageSchema, $url.href, requestInit, options);
 
   return new OffsetLimitPagePromise(
-    fetchResult as Promise<ZodFetchResult<OffsetLimitPageResponse<z.output<TItemSchema>>>>,
+    fetchResult as Promise<
+      ZodFetchResult<OffsetLimitPageResponse<inferZodSchemaOutput<TItemSchema>>>
+    >,
     schema,
     url,
     params,
@@ -195,12 +218,12 @@ async function traceZodFetch<T>(
   );
 }
 
-async function _doZodFetch<TResponseBodySchema extends z.ZodTypeAny>(
+async function _doZodFetch<TResponseBodySchema extends AnyZodSchema>(
   schema: TResponseBodySchema,
   url: string,
   requestInit?: PromiseOrValue<RequestInit>,
-  options?: ZodFetchOptions<z.output<TResponseBodySchema>>
-): Promise<ZodFetchResult<z.output<TResponseBodySchema>>> {
+  options?: ZodFetchOptions<inferZodSchemaOutput<TResponseBodySchema>>
+): Promise<ZodFetchResult<inferZodSchemaOutput<TResponseBodySchema>>> {
   let $requestInit = await requestInit;
 
   return traceZodFetch({ url, requestInit: $requestInit, options }, async (span) => {
@@ -223,13 +246,13 @@ async function _doZodFetch<TResponseBodySchema extends z.ZodTypeAny>(
   });
 }
 
-async function _doZodFetchWithRetries<TResponseBodySchema extends z.ZodTypeAny>(
+async function _doZodFetchWithRetries<TResponseBodySchema extends AnyZodSchema>(
   schema: TResponseBodySchema,
   url: string,
   requestInit?: RequestInit,
   options?: ZodFetchOptions,
   attempt = 1
-): Promise<ZodFetchResult<z.output<TResponseBodySchema>>> {
+): Promise<ZodFetchResult<inferZodSchemaOutput<TResponseBodySchema>>> {
   try {
     const response = await context.with(suppressTracing(context.active()), () =>
       fetch(url, requestInitWithCache(requestInit))
@@ -470,12 +493,12 @@ export class ApiPromise<T> extends Promise<T> {
   }
 }
 
-export class CursorPagePromise<TItemSchema extends z.ZodTypeAny>
-  extends ApiPromise<CursorPage<z.output<TItemSchema>>>
-  implements AsyncIterable<z.output<TItemSchema>>
+export class CursorPagePromise<TItemSchema extends AnyZodSchema>
+  extends ApiPromise<CursorPage<inferZodSchemaOutput<TItemSchema>>>
+  implements AsyncIterable<inferZodSchemaOutput<TItemSchema>>
 {
   constructor(
-    result: Promise<ZodFetchResult<CursorPageResponse<z.output<TItemSchema>>>>,
+    result: Promise<ZodFetchResult<CursorPageResponse<inferZodSchemaOutput<TItemSchema>>>>,
     private schema: TItemSchema,
     private url: string,
     private params: FetchCursorPageParams,
@@ -490,7 +513,9 @@ export class CursorPagePromise<TItemSchema extends z.ZodTypeAny>
     );
   }
 
-  #fetchPage(params: Omit<CursorPageParams, "limit">): Promise<CursorPage<z.output<TItemSchema>>> {
+  #fetchPage(
+    params: Omit<CursorPageParams, "limit">
+  ): Promise<CursorPage<inferZodSchemaOutput<TItemSchema>>> {
     return zodfetchCursorPage(
       this.schema,
       this.url,
@@ -515,12 +540,12 @@ export class CursorPagePromise<TItemSchema extends z.ZodTypeAny>
   }
 }
 
-export class OffsetLimitPagePromise<TItemSchema extends z.ZodTypeAny>
-  extends ApiPromise<OffsetLimitPage<z.output<TItemSchema>>>
-  implements AsyncIterable<z.output<TItemSchema>>
+export class OffsetLimitPagePromise<TItemSchema extends AnyZodSchema>
+  extends ApiPromise<OffsetLimitPage<inferZodSchemaOutput<TItemSchema>>>
+  implements AsyncIterable<inferZodSchemaOutput<TItemSchema>>
 {
   constructor(
-    result: Promise<ZodFetchResult<OffsetLimitPageResponse<z.output<TItemSchema>>>>,
+    result: Promise<ZodFetchResult<OffsetLimitPageResponse<inferZodSchemaOutput<TItemSchema>>>>,
     private schema: TItemSchema,
     private url: string,
     private params: FetchOffsetLimitPageParams,
@@ -541,7 +566,7 @@ export class OffsetLimitPagePromise<TItemSchema extends z.ZodTypeAny>
 
   #fetchPage(
     params: Omit<FetchOffsetLimitPageParams, "limit">
-  ): Promise<OffsetLimitPage<z.output<TItemSchema>>> {
+  ): Promise<OffsetLimitPage<inferZodSchemaOutput<TItemSchema>>> {
     return zodfetchOffsetLimitPage(
       this.schema,
       this.url,
@@ -644,17 +669,17 @@ function injectRequestIdempotencyKey(
   };
 }
 
-export type ZodFetchSSEMessageValueSchema<
-  TDiscriminatedUnion extends z.ZodDiscriminatedUnion<any, any>,
-> = z.ZodFirstPartySchemaTypes | TDiscriminatedUnion;
+export type ZodFetchSSEMessageValueSchema<TSchema extends AnyZodSchema = AnyZodSchema> = TSchema;
 
 export interface ZodFetchSSEMessageCatalogSchema {
-  [key: string]: ZodFetchSSEMessageValueSchema<any>;
+  [key: string]: AnyZodSchema;
 }
 
 export type ZodFetchSSEMessageHandlers<TCatalogSchema extends ZodFetchSSEMessageCatalogSchema> =
   Partial<{
-    [K in keyof TCatalogSchema]: (payload: z.infer<TCatalogSchema[K]>) => Promise<void> | void;
+    [K in keyof TCatalogSchema]: (
+      payload: inferZodSchemaOutput<TCatalogSchema[K]>
+    ) => Promise<void> | void;
   }>;
 
 export type ZodFetchSSEOptions<TMessageCatalog extends ZodFetchSSEMessageCatalogSchema> = {
@@ -699,6 +724,10 @@ export class ZodFetchSSEResult<TMessageCatalog extends ZodFetchSSEMessageCatalog
 
       const schema = this.options.messages[type];
 
+      if (!schema) {
+        return;
+      }
+
       const result = schema.safeParse(payload);
 
       if (result.success) {
@@ -734,12 +763,12 @@ export type ApiResult<TSuccessResult> =
       statusCode?: number;
     };
 
-export async function wrapZodFetch<T extends z.ZodTypeAny>(
+export async function wrapZodFetch<T extends AnyZodSchema>(
   schema: T,
   url: string,
   requestInit?: RequestInit,
-  options?: ZodFetchOptions<z.output<T>>
-): Promise<ApiResult<z.infer<T>>> {
+  options?: ZodFetchOptions<inferZodSchemaOutput<T>>
+): Promise<ApiResult<inferZodSchemaOutput<T>>> {
   try {
     const response = await zodfetch(schema, url, requestInit, {
       retry: {
diff --git a/packages/core/src/v3/apiClient/index.ts b/packages/core/src/v3/apiClient/index.ts
index 23f13f37573..e2ce190e3f5 100644
--- a/packages/core/src/v3/apiClient/index.ts
+++ b/packages/core/src/v3/apiClient/index.ts
@@ -1,5 +1,5 @@
 import { nanoid } from "nanoid";
-import { z } from "zod";
+import { z } from "zod/v4";
 import { VERSION } from "../../version.js";
 import { isAdditionalApiKey } from "../apiKeys.js";
 import type { ApiClientConfiguration } from "../apiClientManager-api.js";
@@ -1903,7 +1903,7 @@ export class ApiClient {
 
   async generateJWTClaims(requestOptions?: ZodFetchOptions): Promise<Record<string, any>> {
     return zodfetch(
-      z.record(z.any()),
+      z.record(z.string(), z.any()),
       `${this.baseUrl}/api/v1/auth/jwt/claims`,
       {
         method: "POST",
diff --git a/packages/core/src/v3/apiClient/stream.ts b/packages/core/src/v3/apiClient/stream.ts
index ec35f1deb63..0124b140172 100644
--- a/packages/core/src/v3/apiClient/stream.ts
+++ b/packages/core/src/v3/apiClient/stream.ts
@@ -1,4 +1,4 @@
-import type { z } from "zod";
+import type { AnyZodSchema, inferZodSchemaOutput } from "../types/schemas.js";
 import {
   type Offset,
   FetchError,
@@ -22,12 +22,12 @@ export type ZodShapeStreamOptions = {
   onError?: (e: Error) => void;
 };
 
-export type ZodShapeStreamInstance<TShapeSchema extends z.ZodTypeAny> = {
-  stream: AsyncIterableStream<z.output<TShapeSchema>>;
+export type ZodShapeStreamInstance<TShapeSchema extends AnyZodSchema> = {
+  stream: AsyncIterableStream<inferZodSchemaOutput<TShapeSchema>>;
   stop: (delay?: number) => void;
 };
 
-export function zodShapeStream<TShapeSchema extends z.ZodTypeAny>(
+export function zodShapeStream<TShapeSchema extends AnyZodSchema>(
   schema: TShapeSchema,
   url: string,
   options?: ZodShapeStreamOptions
@@ -59,7 +59,7 @@ export function zodShapeStream<TShapeSchema extends z.ZodTypeAny>(
   const readableShape = new ReadableShapeStream(shapeStream);
 
   const stream = readableShape.stream.pipeThrough(
-    new TransformStream<unknown, z.output<TShapeSchema>>({
+    new TransformStream<unknown, inferZodSchemaOutput<TShapeSchema>>({
       async transform(chunk, controller) {
         const result = schema.safeParse(chunk);
 
@@ -73,7 +73,7 @@ export function zodShapeStream<TShapeSchema extends z.ZodTypeAny>(
   );
 
   return {
-    stream: stream as AsyncIterableStream<z.output<TShapeSchema>>,
+    stream: stream as AsyncIterableStream<inferZodSchemaOutput<TShapeSchema>>,
     stop: (delay?: number) => {
       if (delay) {
         setTimeout(() => {
diff --git a/packages/core/src/v3/apiClient/zodCompatibility.test.ts b/packages/core/src/v3/apiClient/zodCompatibility.test.ts
new file mode 100644
index 00000000000..9d091a51395
--- /dev/null
+++ b/packages/core/src/v3/apiClient/zodCompatibility.test.ts
@@ -0,0 +1,65 @@
+import { afterAll, beforeAll, describe, expect, it } from "vitest";
+import { createServer, type Server } from "node:http";
+import type { AddressInfo } from "node:net";
+import { z as z3 } from "zod/v3";
+import { z as z4 } from "zod/v4";
+import { zodfetchCursorPage, zodfetchOffsetLimitPage } from "./core.js";
+
+describe("Zod pagination compatibility", () => {
+  let server: Server;
+  let baseUrl: string;
+
+  beforeAll(async () => {
+    server = createServer((request, response) => {
+      response.setHeader("content-type", "application/json");
+
+      if (request.url?.startsWith("/cursor")) {
+        response.end(
+          JSON.stringify({
+            data: [{ value: "42" }],
+            pagination: {},
+          })
+        );
+        return;
+      }
+
+      response.end(
+        JSON.stringify({
+          data: [{ value: "42" }],
+          pagination: { currentPage: "1", totalPages: "1", count: "1" },
+        })
+      );
+    });
+
+    await new Promise<void>((resolve) => {
+      server.listen(0, "127.0.0.1", () => {
+        const address = server.address() as AddressInfo;
+        baseUrl = `http://127.0.0.1:${address.port}`;
+        resolve();
+      });
+    });
+  });
+
+  afterAll(async () => {
+    await new Promise<void>((resolve) => server.close(() => resolve()));
+  });
+
+  it.each([
+    ["Zod 3", z3.object({ value: z3.coerce.number() })],
+    ["Zod 4", z4.object({ value: z4.coerce.number() })],
+  ])("parses cursor pages with %s caller schemas", async (_name, schema) => {
+    const page = await zodfetchCursorPage(schema, `${baseUrl}/cursor`, {});
+
+    expect(page.data).toEqual([{ value: 42 }]);
+  });
+
+  it.each([
+    ["Zod 3", z3.object({ value: z3.coerce.number() })],
+    ["Zod 4", z4.object({ value: z4.coerce.number() })],
+  ])("parses offset pages with %s caller schemas", async (_name, schema) => {
+    const page = await zodfetchOffsetLimitPage(schema, `${baseUrl}/offset`, {});
+
+    expect(page.data).toEqual([{ value: 42 }]);
+    expect(page.pagination).toEqual({ currentPage: 1, totalPages: 1, count: 1 });
+  });
+});
diff --git a/packages/core/src/v3/errors.ts b/packages/core/src/v3/errors.ts
index 1fc7c5bce6c..d42da7c5326 100644
--- a/packages/core/src/v3/errors.ts
+++ b/packages/core/src/v3/errors.ts
@@ -1,4 +1,4 @@
-import type { z } from "zod";
+import type { z } from "zod/v4";
 import type { DeploymentErrorData } from "./schemas/api.js";
 import type { WorkerManifest } from "./schemas/build.js";
 import { ImportTaskFileErrors } from "./schemas/build.js";
@@ -8,6 +8,7 @@ import { TaskMetadataFailedToParseData } from "./schemas/messages.js";
 import { links } from "./links.js";
 import type { ExceptionEventProperties } from "./schemas/openTelemetry.js";
 import { assertExhaustive } from "../utils.js";
+import type { ZodIssueLike } from "./types/schemas.js";
 
 /**
  * If you throw this, it will get converted into an INTERNAL_ERROR
@@ -484,7 +485,7 @@ function correctStackTraceLine(line: string, projectDir?: string, isDev?: boolea
   return line.trim();
 }
 
-export function groupTaskMetadataIssuesByTask(tasks: any, issues: z.ZodIssue[]) {
+export function groupTaskMetadataIssuesByTask(tasks: any, issues: ReadonlyArray<ZodIssueLike>) {
   return issues.reduce(
     (acc, issue) => {
       if (issue.path.length === 0) {
@@ -553,7 +554,7 @@ export class UncaughtExceptionError extends Error {
 
 export class TaskMetadataParseError extends Error {
   constructor(
-    public readonly zodIssues: z.ZodIssue[],
+    public readonly zodIssues: ReadonlyArray<ZodIssueLike>,
     public readonly tasks: any
   ) {
     super(`Failed to parse task metadata`);
diff --git a/packages/core/src/v3/index.ts b/packages/core/src/v3/index.ts
index 10551fca6f6..41af37e9754 100644
--- a/packages/core/src/v3/index.ts
+++ b/packages/core/src/v3/index.ts
@@ -83,8 +83,13 @@ export * from "./config.js";
 export {
   getSchemaParseFn,
   type AnySchemaParseFn,
+  type AnyZodSchema,
   type SchemaParseFn,
+  type ZodErrorLike,
+  type ZodIssueLike,
   type inferSchemaOut,
+  type inferZodSchemaInput,
+  type inferZodSchemaOutput,
   isSchemaZodEsque,
   isSchemaValibotEsque,
   isSchemaArkTypeEsque,
diff --git a/packages/core/src/v3/runEngineWorker/supervisor/http.ts b/packages/core/src/v3/runEngineWorker/supervisor/http.ts
index 450be432577..a80edccc202 100644
--- a/packages/core/src/v3/runEngineWorker/supervisor/http.ts
+++ b/packages/core/src/v3/runEngineWorker/supervisor/http.ts
@@ -1,4 +1,4 @@
-import { z } from "zod";
+import { z } from "zod/v4";
 import type {
   WorkerApiConnectRequestBody,
   WorkerApiDequeueRequestBody,
@@ -27,6 +27,7 @@ import { wrapZodFetch, type ApiResult, type ZodFetchOptions } from "../../zodfet
 import { createHeaders } from "../util.js";
 import { WORKER_HEADERS } from "../consts.js";
 import { SimpleStructuredLogger } from "../../utils/structuredLogger.js";
+import type { AnyZodSchema, inferZodSchemaOutput } from "../../types/schemas.js";
 
 type SupervisorHttpClientOptions = SupervisorClientCommonOptions;
 
@@ -61,13 +62,13 @@ export class SupervisorHttpClient {
     }
   }
 
-  private async request<T extends z.ZodTypeAny>(
+  private async request<T extends AnyZodSchema>(
     name: string,
     schema: T,
     url: string,
     requestInit?: RequestInit,
-    options?: ZodFetchOptions<z.output<T>>
-  ): Promise<ApiResult<z.infer<T>>> {
+    options?: ZodFetchOptions<inferZodSchemaOutput<T>>
+  ): Promise<ApiResult<inferZodSchemaOutput<T>>> {
     const start = performance.now();
     const result = await wrapZodFetch(schema, url, requestInit, options);
 
diff --git a/packages/core/src/v3/runEngineWorker/supervisor/schemas.ts b/packages/core/src/v3/runEngineWorker/supervisor/schemas.ts
index e5360c6ed6b..37be07030e9 100644
--- a/packages/core/src/v3/runEngineWorker/supervisor/schemas.ts
+++ b/packages/core/src/v3/runEngineWorker/supervisor/schemas.ts
@@ -1,4 +1,5 @@
-import { z } from "zod";
+import { z } from "zod/v4";
+import { discriminatedUnion } from "../../utils/zod.js";
 import { TaskRunExecutionResult } from "../../schemas/common.js";
 import {
   MachineResources,
@@ -28,7 +29,7 @@ export const WorkerApiHeartbeatResponseBody = z.object({
 });
 export type WorkerApiHeartbeatResponseBody = z.infer<typeof WorkerApiHeartbeatResponseBody>;
 
-export const WorkerApiSuspendRunRequestBody = z.discriminatedUnion("success", [
+export const WorkerApiSuspendRunRequestBody = discriminatedUnion("success", [
   z.object({
     success: z.literal(true),
     checkpoint: CheckpointInput,
@@ -51,7 +52,7 @@ export type WorkerApiContinueRunExecutionRequestBody = z.infer<
 >;
 
 export const WorkerApiConnectRequestBody = z.object({
-  metadata: z.record(z.any()),
+  metadata: z.record(z.string(), z.any()),
 });
 export type WorkerApiConnectRequestBody = z.infer<typeof WorkerApiConnectRequestBody>;
 
@@ -104,7 +105,7 @@ export type WorkerApiRunAttemptStartRequestBody = z.infer<
 
 export const WorkerApiRunAttemptStartResponseBody = StartRunAttemptResult.and(
   z.object({
-    envVars: z.record(z.string()),
+    envVars: z.record(z.string(), z.string()),
   })
 );
 export type WorkerApiRunAttemptStartResponseBody = z.infer<
diff --git a/packages/core/src/v3/runEngineWorker/workload/http.ts b/packages/core/src/v3/runEngineWorker/workload/http.ts
index 02e5d80b911..b2581c11849 100644
--- a/packages/core/src/v3/runEngineWorker/workload/http.ts
+++ b/packages/core/src/v3/runEngineWorker/workload/http.ts
@@ -1,4 +1,4 @@
-import { z } from "zod";
+import { z } from "zod/v4";
 import type {
   WorkloadHeartbeatRequestBody,
   WorkloadRunAttemptCompleteRequestBody,
diff --git a/packages/core/src/v3/runEngineWorker/workload/schemas.ts b/packages/core/src/v3/runEngineWorker/workload/schemas.ts
index 14f3b8efe35..1abe9214de5 100644
--- a/packages/core/src/v3/runEngineWorker/workload/schemas.ts
+++ b/packages/core/src/v3/runEngineWorker/workload/schemas.ts
@@ -1,4 +1,5 @@
-import { z } from "zod";
+import { z } from "zod/v4";
+import { discriminatedUnion } from "../../utils/zod.js";
 import {
   WorkerApiRunHeartbeatRequestBody,
   WorkerApiHeartbeatResponseBody,
@@ -19,7 +20,7 @@ export type WorkloadHeartbeatRequestBody = z.infer<typeof WorkloadHeartbeatReque
 export const WorkloadHeartbeatResponseBody = WorkerApiHeartbeatResponseBody;
 export type WorkloadHeartbeatResponseBody = z.infer<typeof WorkloadHeartbeatResponseBody>;
 
-export const WorkloadSuspendRunResponseBody = z.discriminatedUnion("ok", [
+export const WorkloadSuspendRunResponseBody = discriminatedUnion("ok", [
   z.object({
     ok: z.literal(true),
   }),
diff --git a/packages/core/src/v3/schemas/api-type.test.ts b/packages/core/src/v3/schemas/api-type.test.ts
index 39fb3131ce1..73c697969cd 100644
--- a/packages/core/src/v3/schemas/api-type.test.ts
+++ b/packages/core/src/v3/schemas/api-type.test.ts
@@ -141,6 +141,14 @@ describe("InitializeDeploymentRequestBody", () => {
 });
 
 describe("TriggerTaskRequestBody", () => {
+  it("accepts a missing payload", () => {
+    const result = TriggerTaskRequestBody.safeParse({
+      options: {},
+    });
+
+    expect(result.success).toBe(true);
+  });
+
   it("accepts application/store payload as a non-empty string", () => {
     const result = TriggerTaskRequestBody.safeParse({
       payload: "packets/payloads/file.json",
diff --git a/packages/core/src/v3/schemas/api.ts b/packages/core/src/v3/schemas/api.ts
index 3f6ba0aeced..31902a6b15f 100644
--- a/packages/core/src/v3/schemas/api.ts
+++ b/packages/core/src/v3/schemas/api.ts
@@ -1,4 +1,5 @@
-import { z } from "zod";
+import { z } from "zod/v4";
+import { discriminatedUnion } from "../utils/zod.js";
 import { DeserializedJsonSchema } from "../../schemas/json.js";
 import {
   FlushedRunMetadata,
@@ -202,8 +203,8 @@ const ConcurrencyKeySchema = z.union([z.string(), z.number()]).transform((value)
 
 export const TriggerTaskRequestBody = z
   .object({
-    payload: z.any(),
-    context: z.any(),
+    payload: z.any().optional(),
+    context: z.any().optional(),
     options: z
       .object({
         /** @deprecated engine v1 only */
@@ -254,7 +255,7 @@ export const TriggerTaskRequestBody = z
         machine: MachinePresetName.optional(),
         maxAttempts: z.number().int().optional(),
         maxDuration: z.number().optional(),
-        metadata: z.any(),
+        metadata: z.any().optional(),
         metadataType: z.string().optional(),
         payloadType: z.string().optional(),
         /**
@@ -312,8 +313,8 @@ export type BatchTriggerTaskRequestBody = z.infer<typeof BatchTriggerTaskRequest
 
 export const BatchTriggerTaskItem = z.object({
   task: z.string(),
-  payload: z.any(),
-  context: z.any(),
+  payload: z.any().optional(),
+  context: z.any().optional(),
   options: z
     .object({
       concurrencyKey: ConcurrencyKeySchema.optional(),
@@ -332,7 +333,7 @@ export const BatchTriggerTaskItem = z.object({
       machine: MachinePresetName.optional(),
       maxAttempts: z.number().int().optional(),
       maxDuration: z.number().optional(),
-      metadata: z.any(),
+      metadata: z.any().optional(),
       metadataType: z.string().optional(),
       parentAttempt: z.string().optional(),
       payloadType: z.string().optional(),
@@ -472,7 +473,7 @@ export type CreateBatchResponse = z.infer<typeof CreateBatchResponse>;
  *
  * `options` reuses the strict shape from BatchTriggerTaskItem so that the
  * Phase-2 streaming path validates option fields identically to the V2/V3
- * batch trigger endpoints — historically this used z.record(z.unknown()) and
+ * batch trigger endpoints — historically this used z.record(z.string(), z.unknown()) and
  * let invalid values (e.g. numeric concurrencyKey) reach Prisma.
  */
 export const BatchItemNDJSON = z.object({
@@ -544,7 +545,7 @@ export const RescheduleRunRequestBody = z.object({
 export type RescheduleRunRequestBody = z.infer<typeof RescheduleRunRequestBody>;
 
 export const GetEnvironmentVariablesResponseBody = z.object({
-  variables: z.record(z.string()),
+  variables: z.record(z.string(), z.string()),
 });
 
 export type GetEnvironmentVariablesResponseBody = z.infer<
@@ -658,7 +659,7 @@ export type CreateArtifactRequestBody = z.infer<typeof CreateArtifactRequestBody
 export const CreateArtifactResponseBody = z.object({
   artifactKey: z.string(),
   uploadUrl: z.string(),
-  uploadFields: z.record(z.string()),
+  uploadFields: z.record(z.string(), z.string()),
   expiresAt: z.string().datetime(),
 });
 
@@ -855,7 +856,7 @@ export const DeploymentFinalizedEvent = z.object({
   }),
 });
 
-export const DeploymentEvent = z.discriminatedUnion("type", [
+export const DeploymentEvent = discriminatedUnion("type", [
   DeploymentLogEvent,
   DeploymentFinalizedEvent,
 ]);
@@ -1204,7 +1205,7 @@ const CommonRunFields = {
   costInCents: z.number(),
   baseCostInCents: z.number(),
   durationMs: z.number(),
-  metadata: z.record(z.any()).optional(),
+  metadata: z.record(z.string(), z.any()).optional(),
   taskKind: z.string().optional(),
   region: z.string().optional(),
 };
@@ -1302,22 +1303,20 @@ const BulkActionSelectionRequestBody = {
   name: z.string().max(255, "Name must be less than 255 characters").optional(),
 };
 
-export const CreateBulkActionRequestBody = z
-  .discriminatedUnion("action", [
-    z.object({
-      action: z.literal("cancel"),
-      targetRegion: z.never().optional(),
-      ...BulkActionSelectionRequestBody,
-    }),
-    z.object({
-      action: z.literal("replay"),
-      targetRegion: z.string().optional(),
-      ...BulkActionSelectionRequestBody,
-    }),
-  ])
-  .refine((body) => (body.filter ? 1 : 0) + (body.runIds ? 1 : 0) === 1, {
-    message: "Exactly one of filter or runIds must be provided",
-  });
+export const CreateBulkActionRequestBody = discriminatedUnion("action", [
+  z.object({
+    action: z.literal("cancel"),
+    targetRegion: z.never().optional(),
+    ...BulkActionSelectionRequestBody,
+  }),
+  z.object({
+    action: z.literal("replay"),
+    targetRegion: z.string().optional(),
+    ...BulkActionSelectionRequestBody,
+  }),
+]).refine((body) => (body.filter ? 1 : 0) + (body.runIds ? 1 : 0) === 1, {
+  message: "Exactly one of filter or runIds must be provided",
+});
 
 export type CreateBulkActionRequestBody = z.infer<typeof CreateBulkActionRequestBody>;
 
@@ -1385,17 +1384,15 @@ export type UpdateEnvironmentVariableRequestBody = z.infer<
 >;
 
 export const ImportEnvironmentVariablesRequestBody = z.object({
-  variables: z.record(z.string()),
-  parentVariables: z.record(z.string()).optional(),
+  variables: z.record(z.string(), z.string()),
+  parentVariables: z.record(z.string(), z.string()).optional(),
   override: z.boolean().optional(),
   // When omitted, variables default to non-secret (the DB default is false).
   isSecret: z.boolean().optional(),
-  source: z
-    .discriminatedUnion("type", [
-      z.object({ type: z.literal("user"), userId: z.string() }),
-      z.object({ type: z.literal("integration"), integration: z.string() }),
-    ])
-    .optional(),
+  source: discriminatedUnion("type", [
+    z.object({ type: z.literal("user"), userId: z.string() }),
+    z.object({ type: z.literal("integration"), integration: z.string() }),
+  ]).optional(),
 });
 
 export type ImportEnvironmentVariablesRequestBody = z.infer<
@@ -1443,7 +1440,7 @@ export const UpdateMetadataRequestBody = FlushedRunMetadata;
 export type UpdateMetadataRequestBody = z.infer<typeof UpdateMetadataRequestBody>;
 
 export const UpdateMetadataResponseBody = z.object({
-  metadata: z.record(DeserializedJsonSchema),
+  metadata: z.record(z.string(), DeserializedJsonSchema),
 });
 
 export type UpdateMetadataResponseBody = z.infer<typeof UpdateMetadataResponseBody>;
@@ -1715,7 +1712,7 @@ export type CompleteWaitpointTokenRequestBody = z.infer<typeof CompleteWaitpoint
  * server's trigger machinery.
  */
 export const SessionTriggerConfig = z.object({
-  basePayload: z.record(z.unknown()),
+  basePayload: z.record(z.string(), z.unknown()),
   machine: MachinePresetName.optional(),
   queue: z.string().max(128).optional(),
   tags: z.array(z.string().max(128)).max(5).optional(),
@@ -1758,7 +1755,7 @@ export const CreateSessionRequestBody = z.object({
   /** Up to 10 tags for dashboard filtering. */
   tags: z.array(z.string().max(128)).max(10).optional(),
   /** Arbitrary JSON metadata. */
-  metadata: z.record(z.unknown()).optional(),
+  metadata: z.record(z.string(), z.unknown()).optional(),
   /** Absolute expiry timestamp for retention. */
   expiresAt: z.coerce.date().optional(),
 });
@@ -1783,7 +1780,7 @@ export const SessionItem = z.object({
    */
   currentRunId: z.string().nullable().optional(),
   tags: z.array(z.string()),
-  metadata: z.record(z.unknown()).nullable(),
+  metadata: z.record(z.string(), z.unknown()).nullable(),
   closedAt: z.coerce.date().nullable(),
   closedReason: z.string().nullable(),
   expiresAt: z.coerce.date().nullable(),
@@ -1835,7 +1832,7 @@ export type EndAndContinueSessionResponseBody = z.infer<typeof EndAndContinueSes
 
 export const UpdateSessionRequestBody = z.object({
   tags: z.array(z.string().max(128)).max(10).optional(),
-  metadata: z.record(z.unknown()).nullable().optional(),
+  metadata: z.record(z.string(), z.unknown()).nullable().optional(),
   // Null explicitly clears the externalId; non-null values must be non-empty.
   externalId: z
     .union([
@@ -2045,7 +2042,7 @@ export const ApiDeploymentListResponseItem = z.object({
     "TIMED_OUT",
   ]),
   deployedAt: z.coerce.date().optional(),
-  git: z.record(z.any()).optional(),
+  git: z.record(z.string(), z.any()).optional(),
   error: DeploymentErrorData.optional(),
 });
 
@@ -2061,7 +2058,7 @@ export const ApiBranchListResponseBody = z.object({
       name: z.string(),
       createdAt: z.coerce.date(),
       updatedAt: z.coerce.date(),
-      git: z.record(z.any()).optional(),
+      git: z.record(z.string(), z.any()).optional(),
       isPaused: z.boolean(),
     })
   ),
@@ -2087,7 +2084,7 @@ export const RetrieveRunTraceSpanSchema = z.object({
     workerVersion: z.string().optional(),
     queueName: z.string().optional(),
     machinePreset: z.string().optional(),
-    properties: z.record(z.any()).optional(),
+    properties: z.record(z.string(), z.any()).optional(),
     output: z.unknown().optional(),
   }),
 });
@@ -2121,7 +2118,7 @@ export const RetrieveSpanDetailResponseBody = z.object({
   level: z.string(),
   startTime: z.coerce.date(),
   durationMs: z.number(),
-  properties: z.record(z.any()).optional(),
+  properties: z.record(z.string(), z.any()).optional(),
   events: z.array(z.any()).optional(),
   entityType: z.string().optional(),
   ai: z
@@ -2210,7 +2207,7 @@ export type ReadSessionStreamRecordsResponseBody = z.infer<
 >;
 
 export const ResolvePromptRequestBody = z.object({
-  variables: z.record(z.unknown()).default({}),
+  variables: z.record(z.string(), z.unknown()).default({}),
   label: z.string().optional(),
   version: z.number().optional(),
 });
@@ -2225,7 +2222,7 @@ export const ResolvePromptResponseBody = z.object({
     template: z.string().optional(),
     text: z.string().optional(),
     model: z.string().optional().nullable(),
-    config: z.record(z.unknown()).optional().nullable(),
+    config: z.record(z.string(), z.unknown()).optional().nullable(),
   }),
 });
 export type ResolvePromptResponseBody = z.infer<typeof ResolvePromptResponseBody>;
diff --git a/packages/core/src/v3/schemas/batchItemNDJSON.test.ts b/packages/core/src/v3/schemas/batchItemNDJSON.test.ts
index f130bba4450..3eb7004c197 100644
--- a/packages/core/src/v3/schemas/batchItemNDJSON.test.ts
+++ b/packages/core/src/v3/schemas/batchItemNDJSON.test.ts
@@ -58,6 +58,15 @@ describe("concurrencyKey coercion", () => {
   });
 
   describe("BatchTriggerTaskItem", () => {
+    it("accepts a missing payload", () => {
+      const result = BatchTriggerTaskItem.safeParse({
+        task: "user-workflow-tick",
+        options: {},
+      });
+
+      expect(result.success).toBe(true);
+    });
+
     it("coerces a numeric concurrencyKey to a string", () => {
       const result = BatchTriggerTaskItem.safeParse({
         task: "user-workflow-tick",
diff --git a/packages/core/src/v3/schemas/build.ts b/packages/core/src/v3/schemas/build.ts
index 52cae0b2385..a0a0330a09a 100644
--- a/packages/core/src/v3/schemas/build.ts
+++ b/packages/core/src/v3/schemas/build.ts
@@ -1,4 +1,4 @@
-import { z } from "zod";
+import { z } from "zod/v4";
 import { ConfigManifest } from "./config.js";
 import { PromptManifest, QueueManifest, SkillManifest, TaskFile, TaskManifest } from "./schemas.js";
 
@@ -41,6 +41,7 @@ export const BuildManifest = z.object({
   config: ConfigManifest,
   files: z.array(TaskFile),
   sources: z.record(
+    z.string(),
     z.object({
       contents: z.string(),
       contentHash: z.string(),
@@ -56,18 +57,18 @@ export const BuildManifest = z.object({
   configPath: z.string(),
   externals: BuildExternal.array().optional(),
   build: z.object({
-    env: z.record(z.string()).optional(),
+    env: z.record(z.string(), z.string()).optional(),
     commands: z.array(z.string()).optional(),
   }),
   customConditions: z.array(z.string()).optional(),
   deploy: z.object({
-    env: z.record(z.string()).optional(),
+    env: z.record(z.string(), z.string()).optional(),
     sync: z
       .object({
-        env: z.record(z.string()).optional(),
-        parentEnv: z.record(z.string()).optional(),
-        secretEnv: z.record(z.string()).optional(),
-        secretParentEnv: z.record(z.string()).optional(),
+        env: z.record(z.string(), z.string()).optional(),
+        parentEnv: z.record(z.string(), z.string()).optional(),
+        secretEnv: z.record(z.string(), z.string()).optional(),
+        secretParentEnv: z.record(z.string(), z.string()).optional(),
       })
       .optional(),
   }),
@@ -84,7 +85,7 @@ export const BuildManifest = z.object({
     })
     .optional(),
   /** Maps output file paths to their content hashes for deduplication during dev */
-  outputHashes: z.record(z.string()).optional(),
+  outputHashes: z.record(z.string(), z.string()).optional(),
   /** Skills discovered and bundled into `.trigger/skills/{id}/` under `outputPath`. */
   skills: SkillManifest.array().optional(),
 });
@@ -113,7 +114,7 @@ export const WorkerManifest = z.object({
   runtime: BuildRuntime,
   runtimeVersion: z.string().optional(),
   customConditions: z.array(z.string()).optional(),
-  timings: z.record(z.number()).optional(),
+  timings: z.record(z.string(), z.number()).optional(),
   processKeepAlive: z
     .object({
       enabled: z.boolean(),
diff --git a/packages/core/src/v3/schemas/checkpoints.ts b/packages/core/src/v3/schemas/checkpoints.ts
index f11698f2df7..1f8b032966b 100644
--- a/packages/core/src/v3/schemas/checkpoints.ts
+++ b/packages/core/src/v3/schemas/checkpoints.ts
@@ -1,5 +1,5 @@
 import { CheckpointType, DequeuedMessage } from "./runEngine.js";
-import z from "zod";
+import z from "zod/v4";
 
 const _CallbackUrl = z
   .string()
diff --git a/packages/core/src/v3/schemas/common.ts b/packages/core/src/v3/schemas/common.ts
index a6ec4b1002d..8574dbf33bd 100644
--- a/packages/core/src/v3/schemas/common.ts
+++ b/packages/core/src/v3/schemas/common.ts
@@ -1,4 +1,5 @@
-import { z } from "zod";
+import { z } from "zod/v4";
+import { discriminatedUnion } from "../utils/zod.js";
 import { DeserializedJsonSchema } from "../../schemas/json.js";
 import type { RuntimeEnvironmentType as DBRuntimeEnvironmentType } from "@trigger.dev/database";
 
@@ -25,7 +26,7 @@ const MetadataOperationKey = z.string().refine(isSafeMetadataKey, {
 
 export const RunMetadataUpdateOperation = z.object({
   type: z.literal("update"),
-  value: z.record(z.unknown()),
+  value: z.record(z.string(), z.unknown()),
 });
 
 export type RunMetadataUpdateOperation = z.infer<typeof RunMetadataUpdateOperation>;
@@ -69,7 +70,7 @@ export const RunMetadataIncrementKeyOperation = z.object({
 
 export type RunMetadataIncrementKeyOperation = z.infer<typeof RunMetadataIncrementKeyOperation>;
 
-export const RunMetadataChangeOperation = z.discriminatedUnion("type", [
+export const RunMetadataChangeOperation = discriminatedUnion("type", [
   RunMetadataUpdateOperation,
   RunMetadataSetKeyOperation,
   RunMetadataDeleteKeyOperation,
@@ -81,7 +82,7 @@ export const RunMetadataChangeOperation = z.discriminatedUnion("type", [
 export type RunMetadataChangeOperation = z.infer<typeof RunMetadataChangeOperation>;
 
 export const FlushedRunMetadata = z.object({
-  metadata: z.record(DeserializedJsonSchema).optional(),
+  metadata: z.record(z.string(), DeserializedJsonSchema).optional(),
   operations: z.array(RunMetadataChangeOperation).optional(),
   parentOperations: z.array(RunMetadataChangeOperation).optional(),
   rootOperations: z.array(RunMetadataChangeOperation).optional(),
@@ -220,7 +221,7 @@ export type TaskRunInternalError = z.infer<typeof TaskRunInternalError>;
 export const TaskRunErrorCodes = TaskRunInternalError.shape.code.enum;
 export type TaskRunErrorCodes = TaskRunInternalError["code"];
 
-export const TaskRunError = z.discriminatedUnion("type", [
+export const TaskRunError = discriminatedUnion("type", [
   TaskRunBuiltInError,
   TaskRunCustomErrorObject,
   TaskRunStringError,
@@ -244,7 +245,7 @@ export const TaskRun = z.object({
   idempotencyKeyScope: z.enum(["run", "attempt", "global"]).optional(),
   maxAttempts: z.number().optional(),
   version: z.string().optional(),
-  metadata: z.record(DeserializedJsonSchema).optional(),
+  metadata: z.record(z.string(), DeserializedJsonSchema).optional(),
   maxDuration: z.number().optional(),
   /** The priority of the run. Wih a value of 10 it will be dequeued before runs that were triggered 9 seconds before it (assuming they had no priority set).  */
   priority: z.number().optional(),
@@ -365,7 +366,7 @@ export const TaskRunExecution = z.object({
   attempt: TaskRunExecutionAttempt.passthrough(),
   run: TaskRun.and(
     z.object({
-      traceContext: z.record(z.unknown()).optional(),
+      traceContext: z.record(z.string(), z.unknown()).optional(),
       realtimeStreamsVersion: z.string().optional(),
     })
   ),
@@ -408,7 +409,7 @@ export const V3TaskRun = z.object({
   idempotencyKeyScope: z.enum(["run", "attempt", "global"]).optional(),
   maxAttempts: z.number().optional(),
   version: z.string().optional(),
-  metadata: z.record(DeserializedJsonSchema).optional(),
+  metadata: z.record(z.string(), DeserializedJsonSchema).optional(),
   maxDuration: z.number().optional(),
   context: z.unknown(),
   durationMs: z.number(),
@@ -423,7 +424,7 @@ export const V3TaskRunExecution = z.object({
   attempt: V3TaskRunExecutionAttempt,
   run: V3TaskRun.and(
     z.object({
-      traceContext: z.record(z.unknown()).optional(),
+      traceContext: z.record(z.string(), z.unknown()).optional(),
     })
   ),
   queue: TaskRunExecutionQueue,
@@ -537,7 +538,7 @@ export const TaskRunSuccessfulExecutionResult = z.object({
 
 export type TaskRunSuccessfulExecutionResult = z.infer<typeof TaskRunSuccessfulExecutionResult>;
 
-export const TaskRunExecutionResult = z.discriminatedUnion("ok", [
+export const TaskRunExecutionResult = discriminatedUnion("ok", [
   TaskRunSuccessfulExecutionResult,
   TaskRunFailedExecutionResult,
 ]);
diff --git a/packages/core/src/v3/schemas/config.ts b/packages/core/src/v3/schemas/config.ts
index f94098f2802..fa7570125f2 100644
--- a/packages/core/src/v3/schemas/config.ts
+++ b/packages/core/src/v3/schemas/config.ts
@@ -1,4 +1,4 @@
-import { z } from "zod";
+import { z } from "zod/v4";
 
 export const ConfigManifest = z.object({
   project: z.string(),
diff --git a/packages/core/src/v3/schemas/errors.ts b/packages/core/src/v3/schemas/errors.ts
index 192da5b6de7..9862d25f93e 100644
--- a/packages/core/src/v3/schemas/errors.ts
+++ b/packages/core/src/v3/schemas/errors.ts
@@ -1,4 +1,4 @@
-import { z } from "zod";
+import { z } from "zod/v4";
 
 /**
  * The lifecycle state of an error group. Mirrors the dashboard's
diff --git a/packages/core/src/v3/schemas/eventFilter.ts b/packages/core/src/v3/schemas/eventFilter.ts
index 6ddda362108..11d3b8753dc 100644
--- a/packages/core/src/v3/schemas/eventFilter.ts
+++ b/packages/core/src/v3/schemas/eventFilter.ts
@@ -1,4 +1,4 @@
-import { z } from "zod";
+import { z } from "zod/v4";
 
 export const stringPatternMatchers = [
   z.object({
@@ -65,5 +65,5 @@ type EventMatcher = z.infer<typeof EventMatcher>;
 export type EventFilter = { [key: string]: EventMatcher | EventFilter };
 
 export const EventFilter: z.ZodType<EventFilter> = z.lazy(() =>
-  z.record(z.union([EventMatcher, EventFilter]))
+  z.record(z.string(), z.union([EventMatcher, EventFilter]))
 );
diff --git a/packages/core/src/v3/schemas/fetch.ts b/packages/core/src/v3/schemas/fetch.ts
index 88ccad4e357..edf5f581aac 100644
--- a/packages/core/src/v3/schemas/fetch.ts
+++ b/packages/core/src/v3/schemas/fetch.ts
@@ -1,4 +1,5 @@
-import { z } from "zod";
+import { z } from "zod/v4";
+import { discriminatedUnion } from "../utils/zod.js";
 import { RetryOptions } from "./schemas.js";
 import { EventFilter } from "./eventFilter.js";
 import type { Prettify } from "../types/index.js";
@@ -39,7 +40,7 @@ export const FetchRetryBackoffStrategy = RetryOptions.extend({
 /** The `backoff` strategy retries the request with an exponential backoff. */
 export type FetchRetryBackoffStrategy = z.infer<typeof FetchRetryBackoffStrategy>;
 
-export const FetchRetryStrategy = z.discriminatedUnion("strategy", [
+export const FetchRetryStrategy = discriminatedUnion("strategy", [
   FetchRetryHeadersStrategy,
   FetchRetryBackoffStrategy,
 ]);
diff --git a/packages/core/src/v3/schemas/messages.ts b/packages/core/src/v3/schemas/messages.ts
index 1389fcddc40..d70a032b479 100644
--- a/packages/core/src/v3/schemas/messages.ts
+++ b/packages/core/src/v3/schemas/messages.ts
@@ -1,9 +1,10 @@
-import { z } from "zod";
+import { z } from "zod/v4";
 import { ImportTaskFileErrors, WorkerManifest } from "./build.js";
 import { TaskRunExecution, TaskRunExecutionResult } from "./common.js";
 import { RunEngineVersionSchema, TaskRunExecutionMetrics } from "./schemas.js";
 import { CompletedWaitpoint } from "./runEngine.js";
 import { DebugLogPropertiesInput } from "../runEngineWorker/supervisor/schemas.js";
+import type { ZodIssueLike } from "../types/schemas.js";
 
 export const ServerBackgroundWorker = z.object({
   id: z.string(),
@@ -27,7 +28,7 @@ export const UncaughtExceptionMessage = z.object({
 export const TaskMetadataFailedToParseData = z.object({
   version: z.literal("v1").default("v1"),
   tasks: z.unknown(),
-  zodIssues: z.custom<z.ZodIssue[]>((v) => {
+  zodIssues: z.custom<ReadonlyArray<ZodIssueLike>>((v) => {
     return Array.isArray(v) && v.every((issue) => typeof issue === "object" && "message" in issue);
   }),
 });
@@ -90,10 +91,10 @@ export const WorkerToExecutorMessageCatalog = {
     message: z.object({
       version: z.literal("v1").default("v1"),
       execution: TaskRunExecution,
-      traceContext: z.record(z.unknown()),
+      traceContext: z.record(z.string(), z.unknown()),
       metadata: ServerBackgroundWorker,
       metrics: TaskRunExecutionMetrics.optional(),
-      env: z.record(z.string()).optional(),
+      env: z.record(z.string(), z.string()).optional(),
       isWarmStart: z.boolean().optional(),
     }),
   },
diff --git a/packages/core/src/v3/schemas/openTelemetry.ts b/packages/core/src/v3/schemas/openTelemetry.ts
index 47d9d9a50d9..2a21f9ad894 100644
--- a/packages/core/src/v3/schemas/openTelemetry.ts
+++ b/packages/core/src/v3/schemas/openTelemetry.ts
@@ -1,4 +1,4 @@
-import { z } from "zod";
+import { z } from "zod/v4";
 
 export const ExceptionEventProperties = z.object({
   type: z.string().optional(),
@@ -43,7 +43,7 @@ export type AttemptFailedSpanEvent = z.infer<typeof AttemptFailedSpanEvent>;
 export const OtherSpanEvent = z.object({
   name: z.string(),
   time: z.coerce.date(),
-  properties: z.record(z.unknown()),
+  properties: z.record(z.string(), z.unknown()),
 });
 
 export type OtherSpanEvent = z.infer<typeof OtherSpanEvent>;
diff --git a/packages/core/src/v3/schemas/query.ts b/packages/core/src/v3/schemas/query.ts
index 027259e8b74..3735ddfdff2 100644
--- a/packages/core/src/v3/schemas/query.ts
+++ b/packages/core/src/v3/schemas/query.ts
@@ -1,4 +1,5 @@
-import { z } from "zod";
+import { z } from "zod/v4";
+import { discriminatedUnion } from "../utils/zod.js";
 import type { IdempotencyKeyScope } from "../idempotency-key-catalog/catalog.js";
 import type { MachinePresetName, RuntimeEnvironmentType } from "./common.js";
 
@@ -21,7 +22,7 @@ export type QueryExecuteRequestBody = z.infer<typeof QueryExecuteRequestBody>;
  */
 export const QueryExecuteJSONResponseBody = z.object({
   format: z.literal("json"),
-  results: z.array(z.record(z.any())),
+  results: z.array(z.record(z.string(), z.any())),
 });
 
 export type QueryExecuteJSONResponseBody = z.infer<typeof QueryExecuteJSONResponseBody>;
@@ -36,7 +37,7 @@ export const QueryExecuteCSVResponseBody = z.object({
 
 export type QueryExecuteCSVResponseBody = z.infer<typeof QueryExecuteCSVResponseBody>;
 
-export const QueryExecuteResponseBody = z.discriminatedUnion("format", [
+export const QueryExecuteResponseBody = discriminatedUnion("format", [
   QueryExecuteJSONResponseBody,
   QueryExecuteCSVResponseBody,
 ]);
diff --git a/packages/core/src/v3/schemas/queues.ts b/packages/core/src/v3/schemas/queues.ts
index 34a47b34e3e..78d310174dd 100644
--- a/packages/core/src/v3/schemas/queues.ts
+++ b/packages/core/src/v3/schemas/queues.ts
@@ -1,4 +1,4 @@
-import { z } from "zod";
+import { z } from "zod/v4";
 
 const queueTypes = ["task", "custom"] as const;
 
diff --git a/packages/core/src/v3/schemas/resources.ts b/packages/core/src/v3/schemas/resources.ts
index 753324d1257..8dd89aa974b 100644
--- a/packages/core/src/v3/schemas/resources.ts
+++ b/packages/core/src/v3/schemas/resources.ts
@@ -1,4 +1,4 @@
-import { z } from "zod";
+import { z } from "zod/v4";
 import { QueueManifest, RetryOptions, ScheduleMetadata } from "./schemas.js";
 import { MachineConfig } from "./common.js";
 
@@ -46,7 +46,7 @@ export const PromptResource = z.object({
   /** Default model identifier */
   model: z.string().optional(),
   /** Default model config (temperature, maxTokens, etc.) */
-  config: z.record(z.unknown()).optional(),
+  config: z.record(z.string(), z.unknown()).optional(),
   /** JSONSchema7 for template variables */
   variableSchema: z.unknown().optional(),
 });
diff --git a/packages/core/src/v3/schemas/runEngine.ts b/packages/core/src/v3/schemas/runEngine.ts
index 92144364494..b96d823eb67 100644
--- a/packages/core/src/v3/schemas/runEngine.ts
+++ b/packages/core/src/v3/schemas/runEngine.ts
@@ -1,4 +1,5 @@
-import { z } from "zod";
+import { z } from "zod/v4";
+import { discriminatedUnion } from "../utils/zod.js";
 import type { Enum, RuntimeEnvironmentType } from "./common.js";
 import { MachinePreset, TaskRunExecution } from "./common.js";
 import { EnvironmentType } from "./schemas.js";
@@ -223,7 +224,7 @@ export const RunExecutionData = z.object({
 });
 export type RunExecutionData = z.infer<typeof RunExecutionData>;
 
-export const CreateCheckpointResult = z.discriminatedUnion("ok", [
+export const CreateCheckpointResult = discriminatedUnion("ok", [
   z
     .object({
       ok: z.literal(true),
@@ -288,7 +289,7 @@ export const DequeuedMessage = z.object({
     machine: MachinePreset,
     attemptNumber: z.number(),
     masterQueue: z.string(),
-    traceContext: z.record(z.unknown()),
+    traceContext: z.record(z.string(), z.unknown()),
     annotations: RunAnnotations.optional(),
   }),
   environment: z.object({
diff --git a/packages/core/src/v3/schemas/schemas.ts b/packages/core/src/v3/schemas/schemas.ts
index 0b12e7ae3db..8d6b6b79c01 100644
--- a/packages/core/src/v3/schemas/schemas.ts
+++ b/packages/core/src/v3/schemas/schemas.ts
@@ -1,4 +1,5 @@
-import { z } from "zod";
+import { z } from "zod/v4";
+import { discriminatedUnion } from "../utils/zod.js";
 import type { RequireKeys } from "../types/index.js";
 import {
   MachineConfig,
@@ -31,8 +32,8 @@ export type TaskRunExecutionMetrics = z.infer<typeof TaskRunExecutionMetrics>;
 
 export const TaskRunExecutionPayload = z.object({
   execution: TaskRunExecution,
-  traceContext: z.record(z.unknown()),
-  environment: z.record(z.string()).optional(),
+  traceContext: z.record(z.string(), z.unknown()),
+  environment: z.record(z.string(), z.string()).optional(),
   metrics: TaskRunExecutionMetrics.optional(),
 });
 
@@ -56,8 +57,8 @@ export type V3ProdTaskRunExecution = z.infer<typeof V3ProdTaskRunExecution>;
 
 export const V3ProdTaskRunExecutionPayload = z.object({
   execution: V3ProdTaskRunExecution,
-  traceContext: z.record(z.unknown()),
-  environment: z.record(z.string()).optional(),
+  traceContext: z.record(z.string(), z.unknown()),
+  environment: z.record(z.string(), z.string()).optional(),
   metrics: TaskRunExecutionMetrics.optional(),
 });
 
@@ -95,7 +96,7 @@ export const SlidingWindowRateLimit = z.object({
   ]),
 });
 
-export const RateLimitOptions = z.discriminatedUnion("type", [
+export const RateLimitOptions = discriminatedUnion("type", [
   FixedWindowRateLimit,
   SlidingWindowRateLimit,
 ]);
@@ -231,7 +232,7 @@ const promptMetadata = {
   description: z.string().optional(),
   content: z.string().optional(),
   model: z.string().optional(),
-  config: z.record(z.unknown()).optional(),
+  config: z.record(z.string(), z.unknown()).optional(),
   variableSchema: z.unknown().optional(),
 };
 
@@ -320,8 +321,8 @@ export const TaskRunExecutionLazyAttemptPayload = z.object({
   messageId: z.string(),
   isTest: z.boolean(),
   isReplay: z.boolean().default(false),
-  traceContext: z.record(z.unknown()),
-  environment: z.record(z.string()).optional(),
+  traceContext: z.record(z.string(), z.unknown()),
+  environment: z.record(z.string(), z.string()).optional(),
   metrics: TaskRunExecutionMetrics.optional(),
 });
 
diff --git a/packages/core/src/v3/schemas/style.ts b/packages/core/src/v3/schemas/style.ts
index 2f833b800ac..b34b7406fbb 100644
--- a/packages/core/src/v3/schemas/style.ts
+++ b/packages/core/src/v3/schemas/style.ts
@@ -1,4 +1,4 @@
-import { z } from "zod";
+import { z } from "zod/v4";
 
 export const PRIMARY_VARIANT = "primary";
 export const WARM_VARIANT = "warm";
diff --git a/packages/core/src/v3/schemas/tokens.ts b/packages/core/src/v3/schemas/tokens.ts
index ba01f240cdf..c1cd4914b1d 100644
--- a/packages/core/src/v3/schemas/tokens.ts
+++ b/packages/core/src/v3/schemas/tokens.ts
@@ -1,4 +1,4 @@
-import { z } from "zod";
+import { z } from "zod/v4";
 
 export const CreateAuthorizationCodeResponseSchema = z.object({
   url: z.string().url(),
diff --git a/packages/core/src/v3/schemas/warmStart.ts b/packages/core/src/v3/schemas/warmStart.ts
index 1d0e43268e4..56b7a09cf20 100644
--- a/packages/core/src/v3/schemas/warmStart.ts
+++ b/packages/core/src/v3/schemas/warmStart.ts
@@ -1,4 +1,4 @@
-import { z } from "zod";
+import { z } from "zod/v4";
 
 export const WarmStartConnectResponse = z.object({
   connectionTimeoutMs: z.number().optional(),
diff --git a/packages/core/src/v3/schemas/webhooks.ts b/packages/core/src/v3/schemas/webhooks.ts
index b5ed927602e..98b99f86f8a 100644
--- a/packages/core/src/v3/schemas/webhooks.ts
+++ b/packages/core/src/v3/schemas/webhooks.ts
@@ -1,4 +1,5 @@
-import { z } from "zod";
+import { z } from "zod/v4";
+import { discriminatedUnion } from "../utils/zod.js";
 import { RunStatus } from "./api.js";
 import { RuntimeEnvironmentTypeSchema, TaskRunError } from "./common.js";
 
@@ -257,7 +258,7 @@ const commonProperties = {
 };
 
 /** Represents all possible webhook types */
-export const Webhook = z.discriminatedUnion("type", [
+export const Webhook = discriminatedUnion("type", [
   /** Run failed alert webhook */
   z.object({
     ...commonProperties,
diff --git a/packages/core/src/v3/serverOnly/httpServer.ts b/packages/core/src/v3/serverOnly/httpServer.ts
index 8360067d583..c6b26785068 100644
--- a/packages/core/src/v3/serverOnly/httpServer.ts
+++ b/packages/core/src/v3/serverOnly/httpServer.ts
@@ -1,30 +1,31 @@
 import { createServer, type IncomingMessage, type ServerResponse } from "node:http";
-import { z } from "zod";
+import { z } from "zod/v4";
 import { SimpleStructuredLogger } from "../utils/structuredLogger.js";
 import { HttpReply, getJsonBody } from "../apps/http.js";
 import type { Registry } from "prom-client";
 import { Histogram, Counter } from "prom-client";
 import { tryCatch } from "../../utils.js";
+import type { AnyZodSchema, inferZodSchemaOutput } from "../types/schemas.js";
 
 const logger = new SimpleStructuredLogger("http-server");
 
 type RouteHandler<
-  TParams extends z.ZodFirstPartySchemaTypes = z.ZodUnknown,
-  TQuery extends z.ZodFirstPartySchemaTypes = z.ZodUnknown,
-  TBody extends z.ZodFirstPartySchemaTypes = z.ZodUnknown,
+  TParams extends AnyZodSchema = z.ZodUnknown,
+  TQuery extends AnyZodSchema = z.ZodUnknown,
+  TBody extends AnyZodSchema = z.ZodUnknown,
 > = (ctx: {
-  params: z.infer<TParams>;
-  queryParams: z.infer<TQuery>;
-  body: z.infer<TBody>;
+  params: inferZodSchemaOutput<TParams>;
+  queryParams: inferZodSchemaOutput<TQuery>;
+  body: inferZodSchemaOutput<TBody>;
   req: IncomingMessage;
   res: ServerResponse;
   reply: HttpReply;
 }) => Promise<any>;
 
 interface RouteDefinition<
-  TParams extends z.ZodFirstPartySchemaTypes = z.ZodUnknown,
-  TQuery extends z.ZodFirstPartySchemaTypes = z.ZodUnknown,
-  TBody extends z.ZodFirstPartySchemaTypes = z.ZodUnknown,
+  TParams extends AnyZodSchema = z.ZodUnknown,
+  TQuery extends AnyZodSchema = z.ZodUnknown,
+  TBody extends AnyZodSchema = z.ZodUnknown,
 > {
   paramsSchema?: TParams;
   querySchema?: TQuery;
@@ -235,9 +236,9 @@ export class HttpServer {
   }
 
   route<
-    TParams extends z.ZodFirstPartySchemaTypes = z.ZodUnknown,
-    TQuery extends z.ZodFirstPartySchemaTypes = z.ZodUnknown,
-    TBody extends z.ZodFirstPartySchemaTypes = z.ZodUnknown,
+    TParams extends AnyZodSchema = z.ZodUnknown,
+    TQuery extends AnyZodSchema = z.ZodUnknown,
+    TBody extends AnyZodSchema = z.ZodUnknown,
   >(path: `/${string}`, method: HttpMethod, definition: RouteDefinition<TParams, TQuery, TBody>) {
     this.routes[path] = {
       ...this.routes[path],
@@ -284,8 +285,8 @@ export class HttpServer {
   }
 
   private optionalSchema<
-    TSchema extends z.ZodFirstPartySchemaTypes | undefined,
-    TData extends TSchema extends z.ZodFirstPartySchemaTypes ? z.TypeOf<TSchema> : TData,
+    TSchema extends AnyZodSchema | undefined,
+    TData extends TSchema extends AnyZodSchema ? inferZodSchemaOutput<TSchema> : TData,
   >(
     schema: TSchema,
     data: TData
@@ -296,7 +297,7 @@ export class HttpServer {
       }
     | {
         success: true;
-        data: TSchema extends z.ZodFirstPartySchemaTypes ? z.infer<TSchema> : TData;
+        data: TSchema extends AnyZodSchema ? inferZodSchemaOutput<TSchema> : TData;
       } {
     if (!schema) {
       return { success: true, data };
@@ -308,7 +309,10 @@ export class HttpServer {
       return { success: false, error: parsed.error.message };
     }
 
-    return { success: true, data: parsed.data };
+    return {
+      success: true,
+      data: parsed.data as TSchema extends AnyZodSchema ? inferZodSchemaOutput<TSchema> : TData,
+    };
   }
 
   private parseQueryParams(url: string): Record<string, string> {
diff --git a/packages/core/src/v3/sessionStreams/chatSnapshot.ts b/packages/core/src/v3/sessionStreams/chatSnapshot.ts
index 84b204a134d..565a00a57ae 100644
--- a/packages/core/src/v3/sessionStreams/chatSnapshot.ts
+++ b/packages/core/src/v3/sessionStreams/chatSnapshot.ts
@@ -17,7 +17,7 @@
  * recognise a version silently fall back to no-snapshot behaviour.
  */
 
-import { z } from "zod";
+import { z } from "zod/v4";
 
 import type { UIMessage } from "ai";
 
diff --git a/packages/core/src/v3/types/schemas.test.ts b/packages/core/src/v3/types/schemas.test.ts
new file mode 100644
index 00000000000..764c1d89ebf
--- /dev/null
+++ b/packages/core/src/v3/types/schemas.test.ts
@@ -0,0 +1,36 @@
+import { describe, expect, expectTypeOf, it } from "vitest";
+import { z as z3 } from "zod/v3";
+import { z as z4 } from "zod/v4";
+import { getSchemaParseFn, isSchemaZodEsque } from "./schemas.js";
+import { convertToolParametersToSchema, type inferToolParameters } from "./tools.js";
+
+describe("Zod schema compatibility", () => {
+  it("detects and parses Zod 3 schemas", async () => {
+    const schema = z3.object({ name: z3.string() });
+
+    expect(isSchemaZodEsque(schema)).toBe(true);
+    expect(convertToolParametersToSchema(schema)).toBe(schema);
+    await expect(getSchemaParseFn(schema)({ name: "Trigger.dev" })).resolves.toEqual({
+      name: "Trigger.dev",
+    });
+
+    expectTypeOf<inferToolParameters<typeof schema>>().toEqualTypeOf<{ name: string }>();
+  });
+
+  it("detects and parses Zod 4 schemas", async () => {
+    const schema = z4.object({ name: z4.string() });
+
+    expect(isSchemaZodEsque(schema)).toBe(true);
+    expect(convertToolParametersToSchema(schema)).toBe(schema);
+    await expect(getSchemaParseFn(schema)({ name: "Trigger.dev" })).resolves.toEqual({
+      name: "Trigger.dev",
+    });
+
+    expectTypeOf<inferToolParameters<typeof schema>>().toEqualTypeOf<{ name: string }>();
+  });
+
+  it("does not identify non-schemas as Zod schemas", () => {
+    expect(isSchemaZodEsque(null)).toBe(false);
+    expect(isSchemaZodEsque({})).toBe(false);
+  });
+});
diff --git a/packages/core/src/v3/types/schemas.ts b/packages/core/src/v3/types/schemas.ts
index b4121029925..e90ab2cd11f 100644
--- a/packages/core/src/v3/types/schemas.ts
+++ b/packages/core/src/v3/types/schemas.ts
@@ -1,14 +1,34 @@
 export type SchemaZodEsque<TInput, TParsedInput> = {
   _input: TInput;
   _output: TParsedInput;
+  parse: (input: unknown) => TParsedInput;
+  parseAsync: (input: unknown) => Promise<TParsedInput>;
+  safeParse: (
+    input: unknown
+  ) => { success: true; data: TParsedInput } | { success: false; error: any };
+};
+
+export type AnyZodSchema = SchemaZodEsque<any, any>;
+export type inferZodSchemaInput<TSchema extends AnyZodSchema> = TSchema["_input"];
+export type inferZodSchemaOutput<TSchema extends AnyZodSchema> = TSchema["_output"];
+
+export type ZodIssueLike = {
+  message: string;
+  path: ReadonlyArray<PropertyKey>;
+};
+
+export type ZodErrorLike = {
+  message: string;
+  issues: ReadonlyArray<ZodIssueLike>;
 };
 
 export function isSchemaZodEsque<TInput, TParsedInput>(
-  schema: Schema
+  schema: unknown
 ): schema is SchemaZodEsque<TInput, TParsedInput> {
   return (
     typeof schema === "object" &&
-    "_def" in schema &&
+    schema !== null &&
+    ("_zod" in schema || "_def" in schema) &&
     "parse" in schema &&
     "parseAsync" in schema &&
     "safeParse" in schema
diff --git a/packages/core/src/v3/types/tools.ts b/packages/core/src/v3/types/tools.ts
index 9df741dc0ad..52fcf6f3c99 100644
--- a/packages/core/src/v3/types/tools.ts
+++ b/packages/core/src/v3/types/tools.ts
@@ -1,22 +1,26 @@
-import { z } from "zod";
 import type { Schema as AISchema } from "ai";
-import type { Schema } from "./schemas.js";
+import {
+  isSchemaZodEsque,
+  type AnyZodSchema,
+  type inferZodSchemaOutput,
+  type Schema,
+} from "./schemas.js";
 
-export type ToolTaskParameters = z.ZodTypeAny | AISchema<any>;
+export type ToolTaskParameters = AnyZodSchema | AISchema<any>;
 
 export type inferToolParameters<PARAMETERS extends ToolTaskParameters> =
   PARAMETERS extends AISchema<any>
     ? PARAMETERS["_type"]
-    : PARAMETERS extends z.ZodTypeAny
-      ? z.infer<PARAMETERS>
+    : PARAMETERS extends AnyZodSchema
+      ? inferZodSchemaOutput<PARAMETERS>
       : never;
 
 export function convertToolParametersToSchema<TToolParameters extends ToolTaskParameters>(
   toolParameters: TToolParameters
 ): Schema {
-  return toolParameters instanceof z.ZodSchema
+  return isSchemaZodEsque(toolParameters)
     ? toolParameters
-    : convertAISchemaToTaskSchema(toolParameters);
+    : convertAISchemaToTaskSchema(toolParameters as AISchema<any>);
 }
 
 function convertAISchemaToTaskSchema(schema: AISchema<any>): Schema {
diff --git a/packages/core/src/v3/utils/ioSerialization.ts b/packages/core/src/v3/utils/ioSerialization.ts
index 5502afb0981..a63a4397303 100644
--- a/packages/core/src/v3/utils/ioSerialization.ts
+++ b/packages/core/src/v3/utils/ioSerialization.ts
@@ -1,6 +1,6 @@
 import { JSONHeroPath } from "@jsonhero/path";
 import type { Attributes, Span } from "@opentelemetry/api";
-import { z } from "zod";
+import { z } from "zod/v4";
 import type { ApiClient } from "../apiClient/index.js";
 import { apiClientManager } from "../apiClientManager-api.js";
 import {
diff --git a/packages/core/src/v3/utils/zod.ts b/packages/core/src/v3/utils/zod.ts
new file mode 100644
index 00000000000..8f35be3e181
--- /dev/null
+++ b/packages/core/src/v3/utils/zod.ts
@@ -0,0 +1,20 @@
+import { z } from "zod/v4";
+
+/**
+ * Preserve the Zod 4.0-compatible declaration shape while using newer Zod 4
+ * implementations at runtime. Newer releases infer the discriminator as a
+ * second type parameter, which older `zod/v4` permalinks cannot consume.
+ */
+export type CompatibleZodDiscriminatedUnion<
+  Types extends readonly [z.ZodTypeAny, ...z.ZodTypeAny[]],
+> = z.ZodDiscriminatedUnion<Types>;
+
+export function discriminatedUnion<const Types extends readonly [z.ZodTypeAny, ...z.ZodTypeAny[]]>(
+  discriminator: string,
+  options: Types
+): CompatibleZodDiscriminatedUnion<Types> {
+  return z.discriminatedUnion(
+    discriminator,
+    options as any
+  ) as CompatibleZodDiscriminatedUnion<Types>;
+}
diff --git a/packages/core/src/v3/workloadDeploymentToken.ts b/packages/core/src/v3/workloadDeploymentToken.ts
index 4f0d367038f..0fd1fc3543e 100644
--- a/packages/core/src/v3/workloadDeploymentToken.ts
+++ b/packages/core/src/v3/workloadDeploymentToken.ts
@@ -1,4 +1,4 @@
-import { z } from "zod";
+import { z } from "zod/v4";
 import { generateJWT, validateJWT } from "./jwt.js";
 
 /**
diff --git a/packages/core/src/v3/zodIpc.ts b/packages/core/src/v3/zodIpc.ts
index d810d255d7f..ebd5a685df7 100644
--- a/packages/core/src/v3/zodIpc.ts
+++ b/packages/core/src/v3/zodIpc.ts
@@ -1,10 +1,12 @@
 import { randomUUID } from "crypto";
-import { z } from "zod";
+import { z } from "zod/v4";
+import { discriminatedUnion } from "./utils/zod.js";
 import type {
   ExecutorToWorkerMessageCatalog,
   WorkerToExecutorMessageCatalog,
 } from "./schemas/messages.js";
 import { ZodSchemaParsedError } from "./zodMessageHandler.js";
+import type { inferZodSchemaInput, inferZodSchemaOutput } from "./types/schemas.js";
 import type {
   GetSocketCallbackSchema,
   GetSocketMessageSchema,
@@ -18,13 +20,13 @@ import type {
 interface ZodIpcMessageSender<TEmitCatalog extends ZodSocketMessageCatalogSchema> {
   send<K extends GetSocketMessagesWithoutCallback<TEmitCatalog>>(
     type: K,
-    payload: z.input<GetSocketMessageSchema<TEmitCatalog, K>>
+    payload: inferZodSchemaInput<GetSocketMessageSchema<TEmitCatalog, K>>
   ): Promise<void>;
 
   sendWithAck<K extends GetSocketMessagesWithCallback<TEmitCatalog>>(
     type: K,
-    payload: z.input<GetSocketMessageSchema<TEmitCatalog, K>>
-  ): Promise<z.infer<GetSocketCallbackSchema<TEmitCatalog, K>>>;
+    payload: inferZodSchemaInput<GetSocketMessageSchema<TEmitCatalog, K>>
+  ): Promise<inferZodSchemaOutput<GetSocketCallbackSchema<TEmitCatalog, K>>>;
 }
 
 type ZodIpcMessageHandlers<
@@ -32,11 +34,11 @@ type ZodIpcMessageHandlers<
   TEmitCatalog extends ZodSocketMessageCatalogSchema,
 > = Partial<{
   [K in keyof TListenCatalog]: (
-    payload: z.infer<GetSocketMessageSchema<TListenCatalog, K>>,
+    payload: inferZodSchemaOutput<GetSocketMessageSchema<TListenCatalog, K>>,
     sender: ZodIpcMessageSender<TEmitCatalog>
   ) => Promise<
     SocketMessageHasCallback<TListenCatalog, K> extends true
-      ? z.input<GetSocketCallbackSchema<TListenCatalog, K>>
+      ? inferZodSchemaInput<GetSocketCallbackSchema<TListenCatalog, K>>
       : void
   >;
 }>;
@@ -84,7 +86,8 @@ class ZodIpcMessageHandler<
       return;
     }
 
-    const ack = await handler(parsedMessage.payload, this.#sender);
+    // parsedMessage.payload is parsed output at runtime; zod v4 distinguishes input/output
+    const ack = await handler(parsedMessage.payload as Parameters<typeof handler>[0], this.#sender);
 
     return ack;
   }
@@ -114,7 +117,7 @@ class ZodIpcMessageHandler<
   }
 }
 
-const Packet = z.discriminatedUnion("type", [
+const Packet = discriminatedUnion("type", [
   z.object({
     type: z.literal("CONNECT"),
     sessionId: z.string().optional(),
@@ -274,7 +277,7 @@ export class ZodIpcConnection<
 
   async send<K extends GetSocketMessagesWithoutCallback<TEmitCatalog>>(
     type: K,
-    payload: z.input<GetSocketMessageSchema<TEmitCatalog, K>>
+    payload: inferZodSchemaInput<GetSocketMessageSchema<TEmitCatalog, K>>
   ): Promise<void> {
     const schema = this.opts.emitSchema[type]?.["message"];
 
@@ -300,9 +303,9 @@ export class ZodIpcConnection<
 
   public async sendWithAck<K extends GetSocketMessagesWithCallback<TEmitCatalog>>(
     type: K,
-    payload: z.input<GetSocketMessageSchema<TEmitCatalog, K>>,
+    payload: inferZodSchemaInput<GetSocketMessageSchema<TEmitCatalog, K>>,
     timeoutInMs?: number
-  ): Promise<z.infer<GetSocketCallbackSchema<TEmitCatalog, K>>> {
+  ): Promise<inferZodSchemaOutput<GetSocketCallbackSchema<TEmitCatalog, K>>> {
     const currentId = this.#messageCounter++;
 
     return new Promise((resolve, reject) => {
@@ -320,7 +323,7 @@ export class ZodIpcConnection<
         );
       }, timeoutInMs ?? defaultTimeoutInMs);
 
-      this.#acks.set(currentId, { resolve, reject, timeout });
+      this.#acks.set(currentId, { resolve: resolve as (value: unknown) => void, reject, timeout });
 
       const schema = this.opts.emitSchema[type]?.["message"];
 
diff --git a/packages/core/src/v3/zodMessageHandler.test.ts b/packages/core/src/v3/zodMessageHandler.test.ts
new file mode 100644
index 00000000000..7f9db90e5b6
--- /dev/null
+++ b/packages/core/src/v3/zodMessageHandler.test.ts
@@ -0,0 +1,41 @@
+import { describe, expect, it, vi } from "vitest";
+import { z as z3 } from "zod/v3";
+import { z as z4 } from "zod/v4";
+import { ZodMessageSender, sendMessageInCatalog } from "./zodMessageHandler.js";
+
+const schemas = [
+  [
+    "Zod 3",
+    z3.object({ value: z3.string().transform(Number), added: z3.string().default("default") }),
+  ],
+  [
+    "Zod 4",
+    z4.object({ value: z4.string().transform(Number), added: z4.string().default("default") }),
+  ],
+] as const;
+
+describe("Zod message sending", () => {
+  it.each(schemas)("ZodMessageSender preserves the original %s payload", async (_name, schema) => {
+    const catalog = { TEST: schema };
+    const payload = { value: "42", extra: "preserved" };
+    const sender = vi.fn(async (_message: unknown) => {});
+    const messageSender = new ZodMessageSender({ schema: catalog, sender });
+
+    await messageSender.send("TEST", payload);
+
+    expect(sender).toHaveBeenCalledWith({ type: "TEST", payload, version: "v1" });
+  });
+
+  it.each(schemas)(
+    "sendMessageInCatalog preserves the original %s payload",
+    async (_name, schema) => {
+      const catalog = { TEST: schema };
+      const payload = { value: "42", extra: "preserved" };
+      const sender = vi.fn(async (_message: unknown) => {});
+
+      await sendMessageInCatalog(catalog, "TEST", payload, sender);
+
+      expect(sender).toHaveBeenCalledWith({ type: "TEST", payload, version: "v1" });
+    }
+  );
+});
diff --git a/packages/core/src/v3/zodMessageHandler.ts b/packages/core/src/v3/zodMessageHandler.ts
index 2836822faf5..27662d677bf 100644
--- a/packages/core/src/v3/zodMessageHandler.ts
+++ b/packages/core/src/v3/zodMessageHandler.ts
@@ -1,25 +1,29 @@
-import { z } from "zod";
+import { z } from "zod/v4";
+import type {
+  AnyZodSchema,
+  ZodErrorLike,
+  inferZodSchemaInput,
+  inferZodSchemaOutput,
+} from "./types/schemas.js";
 import type { StructuredLogger } from "./utils/structuredLogger.js";
 
 export class ZodSchemaParsedError extends Error {
   constructor(
-    public error: z.ZodError,
+    public error: ZodErrorLike,
     public payload: unknown
   ) {
     super(error.message);
   }
 }
 
-export type ZodMessageValueSchema<TDiscriminatedUnion extends z.ZodDiscriminatedUnion<any, any>> =
-  | z.ZodFirstPartySchemaTypes
-  | TDiscriminatedUnion;
+export type ZodMessageValueSchema<TSchema extends AnyZodSchema = AnyZodSchema> = TSchema;
 
 export interface ZodMessageCatalogSchema {
-  [key: string]: ZodMessageValueSchema<any>;
+  [key: string]: AnyZodSchema;
 }
 
 export type ZodMessageHandlers<TCatalogSchema extends ZodMessageCatalogSchema> = Partial<{
-  [K in keyof TCatalogSchema]: (payload: z.infer<TCatalogSchema[K]>) => Promise<any>;
+  [K in keyof TCatalogSchema]: (payload: inferZodSchemaOutput<TCatalogSchema[K]>) => Promise<any>;
 }>;
 
 export type ZodMessageHandlerOptions<TMessageCatalog extends ZodMessageCatalogSchema> = {
@@ -33,13 +37,13 @@ export type MessageFromSchema<
   TMessageCatalog extends ZodMessageCatalogSchema,
 > = {
   type: K;
-  payload: z.input<TMessageCatalog[K]>;
+  payload: inferZodSchemaInput<TMessageCatalog[K]>;
 };
 
 export type MessagePayloadFromSchema<
   K extends keyof TMessageCatalog,
   TMessageCatalog extends ZodMessageCatalogSchema,
-> = z.output<TMessageCatalog[K]>;
+> = inferZodSchemaOutput<TMessageCatalog[K]>;
 
 export type MessageFromCatalog<TMessageCatalog extends ZodMessageCatalogSchema> = {
   [K in keyof TMessageCatalog]: MessageFromSchema<K, TMessageCatalog>;
@@ -109,7 +113,8 @@ export class ZodMessageHandler<TMessageCatalog extends ZodMessageCatalogSchema>
       };
     }
 
-    const ack = await handler(parsedMessage.data.payload);
+    // parsedMessage.data.payload is parsed output at runtime; zod v4 distinguishes input/output
+    const ack = await handler(parsedMessage.data.payload as Parameters<typeof handler>[0]);
 
     return {
       success: true,
@@ -232,7 +237,7 @@ export function parseMessageFromCatalog<TMessageCatalog extends ZodMessageCatalo
 
 type ZodMessageSenderCallback<TMessageCatalog extends ZodMessageCatalogSchema> = (message: {
   type: keyof TMessageCatalog;
-  payload: z.infer<TMessageCatalog[keyof TMessageCatalog]>;
+  payload: inferZodSchemaOutput<TMessageCatalog[keyof TMessageCatalog]>;
   version: "v1";
 }) => Promise<void>;
 
@@ -262,7 +267,7 @@ export class ZodMessageSender<TMessageCatalog extends ZodMessageCatalogSchema> {
 
   public async send<K extends keyof TMessageCatalog>(
     type: K,
-    payload: z.input<TMessageCatalog[K]>
+    payload: inferZodSchemaInput<TMessageCatalog[K]>
   ) {
     const schema = this.#schema[type];
 
@@ -277,7 +282,13 @@ export class ZodMessageSender<TMessageCatalog extends ZodMessageCatalogSchema> {
     }
 
     try {
-      await this.#sender({ type, payload, version: "v1" });
+      // Preserve the original payload on the wire for backwards compatibility. Validation is
+      // intentionally side-effect-free here; receivers parse the payload into the schema output.
+      await this.#sender({
+        type,
+        payload: payload as unknown as inferZodSchemaOutput<TMessageCatalog[keyof TMessageCatalog]>,
+        version: "v1",
+      });
     } catch (error) {
       console.error("[ZodMessageSender] Failed to send message", error);
     }
@@ -317,7 +328,7 @@ export class ZodMessageSender<TMessageCatalog extends ZodMessageCatalogSchema> {
 export async function sendMessageInCatalog<TMessageCatalog extends ZodMessageCatalogSchema>(
   catalog: TMessageCatalog,
   type: keyof TMessageCatalog,
-  payload: z.input<TMessageCatalog[keyof TMessageCatalog]>,
+  payload: inferZodSchemaInput<TMessageCatalog[keyof TMessageCatalog]>,
   sender: ZodMessageSenderCallback<TMessageCatalog>
 ) {
   const schema = catalog[type];
@@ -332,9 +343,15 @@ export async function sendMessageInCatalog<TMessageCatalog extends ZodMessageCat
     throw new ZodSchemaParsedError(parsedPayload.error, payload);
   }
 
-  await sender({ type, payload, version: "v1" });
+  // Preserve the original payload on the wire for backwards compatibility. Validation is
+  // intentionally side-effect-free here; receivers parse the payload into the schema output.
+  await sender({
+    type,
+    payload: payload as unknown as inferZodSchemaOutput<TMessageCatalog[keyof TMessageCatalog]>,
+    version: "v1",
+  });
 }
 
 export type MessageCatalogToSocketIoEvents<TCatalog extends ZodMessageCatalogSchema> = {
-  [K in keyof TCatalog]: (message: z.infer<TCatalog[K]>) => void;
+  [K in keyof TCatalog]: (message: inferZodSchemaOutput<TCatalog[K]>) => void;
 };
diff --git a/packages/core/src/v3/zodSocket.ts b/packages/core/src/v3/zodSocket.ts
index 32488dd3551..db9afafdaab 100644
--- a/packages/core/src/v3/zodSocket.ts
+++ b/packages/core/src/v3/zodSocket.ts
@@ -1,7 +1,8 @@
 import type { ManagerOptions, Socket, SocketOptions } from "socket.io-client";
 import { io } from "socket.io-client";
-import { z } from "zod";
-import { fromZodError } from "zod-validation-error";
+import { z } from "zod/v4";
+import { fromZodError } from "zod-validation-error/v4";
+import type { inferZodSchemaInput, inferZodSchemaOutput } from "./types/schemas.js";
 import type { StructuredLogger } from "./utils/structuredLogger.js";
 import { LogLevel, SimpleStructuredLogger } from "./utils/structuredLogger.js";
 import type { EventEmitterLike, ZodMessageValueSchema } from "./zodMessageHandler.js";
@@ -20,10 +21,10 @@ export interface ZodSocketMessageCatalogSchema {
 export type ZodMessageCatalogToSocketIoEvents<TCatalog extends ZodSocketMessageCatalogSchema> = {
   [K in keyof TCatalog]: SocketMessageHasCallback<TCatalog, K> extends true
     ? (
-        message: z.infer<GetSocketMessageSchema<TCatalog, K>>,
-        callback: (ack: z.infer<GetSocketCallbackSchema<TCatalog, K>>) => void
+        message: inferZodSchemaOutput<GetSocketMessageSchema<TCatalog, K>>,
+        callback: (ack: inferZodSchemaOutput<GetSocketCallbackSchema<TCatalog, K>>) => void
       ) => void
-    : (message: z.infer<GetSocketMessageSchema<TCatalog, K>>) => void;
+    : (message: inferZodSchemaOutput<GetSocketMessageSchema<TCatalog, K>>) => void;
 };
 
 export type GetSocketMessageSchema<
@@ -34,7 +35,7 @@ export type GetSocketMessageSchema<
 export type InferSocketMessageSchema<
   TRPCCatalog extends ZodSocketMessageCatalogSchema,
   TMessageType extends keyof TRPCCatalog,
-> = z.infer<GetSocketMessageSchema<TRPCCatalog, TMessageType>>;
+> = inferZodSchemaOutput<GetSocketMessageSchema<TRPCCatalog, TMessageType>>;
 
 export type GetSocketCallbackSchema<
   TRPCCatalog extends ZodSocketMessageCatalogSchema,
@@ -46,7 +47,7 @@ export type GetSocketCallbackSchema<
 export type InferSocketCallbackSchema<
   TRPCCatalog extends ZodSocketMessageCatalogSchema,
   TMessageType extends keyof TRPCCatalog,
-> = z.infer<GetSocketCallbackSchema<TRPCCatalog, TMessageType>>;
+> = inferZodSchemaOutput<GetSocketCallbackSchema<TRPCCatalog, TMessageType>>;
 
 export type SocketMessageHasCallback<
   TRPCCatalog extends ZodSocketMessageCatalogSchema,
@@ -56,10 +57,10 @@ export type SocketMessageHasCallback<
 export type ZodSocketMessageHandlers<TCatalogSchema extends ZodSocketMessageCatalogSchema> =
   Partial<{
     [K in keyof TCatalogSchema]: (
-      payload: z.infer<GetSocketMessageSchema<TCatalogSchema, K>>
+      payload: inferZodSchemaOutput<GetSocketMessageSchema<TCatalogSchema, K>>
     ) => Promise<
       SocketMessageHasCallback<TCatalogSchema, K> extends true
-        ? z.input<GetSocketCallbackSchema<TCatalogSchema, K>>
+        ? inferZodSchemaInput<GetSocketCallbackSchema<TCatalogSchema, K>>
         : void
     >;
   }>;
@@ -77,7 +78,7 @@ type MessageFromSocketSchema<
   TMessageCatalog extends ZodSocketMessageCatalogSchema,
 > = {
   type: K;
-  payload: z.input<GetSocketMessageSchema<TMessageCatalog, K>>;
+  payload: inferZodSchemaInput<GetSocketMessageSchema<TMessageCatalog, K>>;
 };
 
 export type MessagesFromSocketCatalog<TMessageCatalog extends ZodSocketMessageCatalogSchema> = {
@@ -128,7 +129,8 @@ export class ZodSocketMessageHandler<TRPCCatalog extends ZodSocketMessageCatalog
       return;
     }
 
-    const ack = await handler(payload);
+    // payload is the parsed output at runtime; zod v4 distinguishes input/output so cast to the handler's expected arg
+    const ack = await handler(payload as Parameters<typeof handler>[0]);
 
     return ack;
   }
@@ -269,7 +271,7 @@ export class ZodSocketMessageSender<TMessageCatalog extends ZodSocketMessageCata
 
   public send<K extends GetSocketMessagesWithoutCallback<TMessageCatalog>>(
     type: K,
-    payload: z.input<GetSocketMessageSchema<TMessageCatalog, K>>
+    payload: inferZodSchemaInput<GetSocketMessageSchema<TMessageCatalog, K>>
   ): void {
     const schema = this.#schema[type]?.["message"];
 
@@ -294,9 +296,9 @@ export class ZodSocketMessageSender<TMessageCatalog extends ZodSocketMessageCata
 
   public async sendWithAck<K extends GetSocketMessagesWithCallback<TMessageCatalog>>(
     type: K,
-    payload: z.input<GetSocketMessageSchema<TMessageCatalog, K>>,
+    payload: inferZodSchemaInput<GetSocketMessageSchema<TMessageCatalog, K>>,
     timeout?: number
-  ): Promise<z.infer<GetSocketCallbackSchema<TMessageCatalog, K>>> {
+  ): Promise<inferZodSchemaOutput<GetSocketCallbackSchema<TMessageCatalog, K>>> {
     const schema = this.#schema[type]?.["message"];
 
     if (!schema) {
@@ -314,7 +316,7 @@ export class ZodSocketMessageSender<TMessageCatalog extends ZodSocketMessageCata
     // @ts-expect-error
     const callbackResult = await socket.emitWithAck(type, { payload, version: "v1" });
 
-    return callbackResult;
+    return callbackResult as inferZodSchemaOutput<GetSocketCallbackSchema<TMessageCatalog, K>>;
   }
 }
 
diff --git a/packages/redis-worker/package.json b/packages/redis-worker/package.json
index 7c014c23436..ef49dfb37f5 100644
--- a/packages/redis-worker/package.json
+++ b/packages/redis-worker/package.json
@@ -28,7 +28,7 @@
     "nanoid": "^5.0.7",
     "p-limit": "^6.2.0",
     "seedrandom": "^3.0.5",
-    "zod": "3.25.76",
+    "zod": "^3.25.76 || ^4.0.0",
     "cron-parser": "^4.9.0"
   },
   "devDependencies": {
@@ -53,5 +53,8 @@
       "import": "./dist/index.js",
       "require": "./dist/index.cjs"
     }
+  },
+  "peerDependencies": {
+    "zod": "^3.25.76 || ^4.0.0"
   }
 }
diff --git a/packages/redis-worker/src/fair-queue/index.ts b/packages/redis-worker/src/fair-queue/index.ts
index e24de876d85..0cc7ec659f3 100644
--- a/packages/redis-worker/src/fair-queue/index.ts
+++ b/packages/redis-worker/src/fair-queue/index.ts
@@ -1,9 +1,10 @@
 import { createRedisClient, type Redis } from "@internal/redis";
 import { SpanKind, type Span } from "@internal/tracing";
 import { Logger } from "@trigger.dev/core/logger";
+import type { AnyZodSchema, inferZodSchemaOutput } from "@trigger.dev/core/v3";
 import { nanoid } from "nanoid";
 import { setInterval } from "node:timers/promises";
-import { type z } from "zod";
+import { type z } from "zod/v4";
 import { isAbortError } from "../utils.js";
 import { ConcurrencyManager } from "./concurrency.js";
 import { MasterQueue } from "./masterQueue.js";
@@ -63,7 +64,7 @@ export * from "./workerQueue.js";
  *
  * @typeParam TPayloadSchema - Zod schema for message payload validation
  */
-export class FairQueue<TPayloadSchema extends z.ZodTypeAny = z.ZodUnknown> {
+export class FairQueue<TPayloadSchema extends AnyZodSchema = z.ZodUnknown> {
   private redis: Redis;
   private keys: FairQueueKeyProducer;
   private scheduler: FairScheduler;
@@ -85,7 +86,9 @@ export class FairQueue<TPayloadSchema extends z.ZodTypeAny = z.ZodUnknown> {
   private visibilityTimeoutMs: number;
   private heartbeatIntervalMs: number;
   private reclaimIntervalMs: number;
-  private workerQueueResolver: (message: StoredMessage<z.infer<TPayloadSchema>>) => string;
+  private workerQueueResolver: (
+    message: StoredMessage<inferZodSchemaOutput<TPayloadSchema>>
+  ) => string;
   private batchClaimSize: number;
 
   // Cooloff state
@@ -264,7 +267,7 @@ export class FairQueue<TPayloadSchema extends z.ZodTypeAny = z.ZodUnknown> {
   /**
    * Enqueue a single message to a queue.
    */
-  async enqueue(options: EnqueueOptions<z.infer<TPayloadSchema>>): Promise<string> {
+  async enqueue(options: EnqueueOptions<inferZodSchemaOutput<TPayloadSchema>>): Promise<string> {
     return this.telemetry.trace(
       "enqueue",
       async (span) => {
@@ -293,7 +296,7 @@ export class FairQueue<TPayloadSchema extends z.ZodTypeAny = z.ZodUnknown> {
         this.queueDescriptorCache.set(options.queueId, descriptor);
 
         // Build stored message
-        const storedMessage: StoredMessage<z.infer<TPayloadSchema>> = {
+        const storedMessage: StoredMessage<inferZodSchemaOutput<TPayloadSchema>> = {
           id: messageId,
           queueId: options.queueId,
           tenantId: options.tenantId,
@@ -356,7 +359,9 @@ export class FairQueue<TPayloadSchema extends z.ZodTypeAny = z.ZodUnknown> {
   /**
    * Enqueue multiple messages to a queue.
    */
-  async enqueueBatch(options: EnqueueBatchOptions<z.infer<TPayloadSchema>>): Promise<string[]> {
+  async enqueueBatch(
+    options: EnqueueBatchOptions<inferZodSchemaOutput<TPayloadSchema>>
+  ): Promise<string[]> {
     return this.telemetry.trace(
       "enqueueBatch",
       async (span) => {
@@ -392,7 +397,7 @@ export class FairQueue<TPayloadSchema extends z.ZodTypeAny = z.ZodUnknown> {
             }
           }
 
-          const storedMessage: StoredMessage<z.infer<TPayloadSchema>> = {
+          const storedMessage: StoredMessage<inferZodSchemaOutput<TPayloadSchema>> = {
             id: messageId,
             queueId: options.queueId,
             tenantId: options.tenantId,
@@ -463,7 +468,7 @@ export class FairQueue<TPayloadSchema extends z.ZodTypeAny = z.ZodUnknown> {
   async getDeadLetterMessages(
     tenantId: string,
     limit: number = 100
-  ): Promise<DeadLetterMessage<z.infer<TPayloadSchema>>[]> {
+  ): Promise<DeadLetterMessage<inferZodSchemaOutput<TPayloadSchema>>[]> {
     if (!this.deadLetterQueueEnabled) {
       return [];
     }
@@ -474,7 +479,7 @@ export class FairQueue<TPayloadSchema extends z.ZodTypeAny = z.ZodUnknown> {
     // Get message IDs with scores (deadLetteredAt timestamps)
     const results = await this.redis.zrange(dlqKey, 0, limit - 1, "WITHSCORES");
 
-    const messages: DeadLetterMessage<z.infer<TPayloadSchema>>[] = [];
+    const messages: DeadLetterMessage<inferZodSchemaOutput<TPayloadSchema>>[] = [];
 
     for (let i = 0; i < results.length; i += 2) {
       const messageId = results[i];
@@ -485,7 +490,9 @@ export class FairQueue<TPayloadSchema extends z.ZodTypeAny = z.ZodUnknown> {
       if (!dataJson) continue;
 
       try {
-        const data = JSON.parse(dataJson) as DeadLetterMessage<z.infer<TPayloadSchema>>;
+        const data = JSON.parse(dataJson) as DeadLetterMessage<
+          inferZodSchemaOutput<TPayloadSchema>
+        >;
         data.deadLetteredAt = parseFloat(deadLetteredAtStr);
         messages.push(data);
       } catch {
@@ -516,7 +523,9 @@ export class FairQueue<TPayloadSchema extends z.ZodTypeAny = z.ZodUnknown> {
           return false;
         }
 
-        const dlqMessage = JSON.parse(dataJson) as DeadLetterMessage<z.infer<TPayloadSchema>>;
+        const dlqMessage = JSON.parse(dataJson) as DeadLetterMessage<
+          inferZodSchemaOutput<TPayloadSchema>
+        >;
 
         // Re-enqueue with reset attempt count
         await this.enqueue({
@@ -1124,7 +1133,7 @@ export class FairQueue<TPayloadSchema extends z.ZodTypeAny = z.ZodUnknown> {
 
     // Claim batch of messages with visibility timeout
     const claimedMessages = await this.visibilityManager.claimBatch<
-      StoredMessage<z.infer<TPayloadSchema>>
+      StoredMessage<inferZodSchemaOutput<TPayloadSchema>>
     >(queueId, queueKey, queueItemsKey, loopId, maxClaimCount, this.visibilityTimeoutMs);
 
     if (claimedMessages.length === 0) {
@@ -1194,7 +1203,7 @@ export class FairQueue<TPayloadSchema extends z.ZodTypeAny = z.ZodUnknown> {
   async getMessageData(
     messageId: string,
     queueId: string
-  ): Promise<StoredMessage<z.infer<TPayloadSchema>> | null> {
+  ): Promise<StoredMessage<inferZodSchemaOutput<TPayloadSchema>> | null> {
     const shardId = this.masterQueue.getShardForQueue(queueId);
     const inflightDataKey = this.keys.inflightDataKey(shardId);
     const dataJson = await this.redis.hget(inflightDataKey, messageId);
@@ -1204,7 +1213,7 @@ export class FairQueue<TPayloadSchema extends z.ZodTypeAny = z.ZodUnknown> {
     }
 
     try {
-      return JSON.parse(dataJson) as StoredMessage<z.infer<TPayloadSchema>>;
+      return JSON.parse(dataJson) as StoredMessage<inferZodSchemaOutput<TPayloadSchema>>;
     } catch {
       this.logger.error("Failed to parse message data", { messageId, queueId });
       return null;
@@ -1236,7 +1245,7 @@ export class FairQueue<TPayloadSchema extends z.ZodTypeAny = z.ZodUnknown> {
 
     // Get stored message for concurrency release
     const dataJson = await this.redis.hget(inflightDataKey, messageId);
-    let storedMessage: StoredMessage<z.infer<TPayloadSchema>> | null = null;
+    let storedMessage: StoredMessage<inferZodSchemaOutput<TPayloadSchema>> | null = null;
     if (dataJson) {
       try {
         storedMessage = JSON.parse(dataJson);
@@ -1291,7 +1300,7 @@ export class FairQueue<TPayloadSchema extends z.ZodTypeAny = z.ZodUnknown> {
 
     // Get stored message for concurrency release
     const dataJson = await this.redis.hget(inflightDataKey, messageId);
-    let storedMessage: StoredMessage<z.infer<TPayloadSchema>> | null = null;
+    let storedMessage: StoredMessage<inferZodSchemaOutput<TPayloadSchema>> | null = null;
     if (dataJson) {
       try {
         storedMessage = JSON.parse(dataJson);
@@ -1356,7 +1365,7 @@ export class FairQueue<TPayloadSchema extends z.ZodTypeAny = z.ZodUnknown> {
       return;
     }
 
-    let storedMessage: StoredMessage<z.infer<TPayloadSchema>>;
+    let storedMessage: StoredMessage<inferZodSchemaOutput<TPayloadSchema>>;
     try {
       storedMessage = JSON.parse(dataJson);
     } catch {
@@ -1390,7 +1399,7 @@ export class FairQueue<TPayloadSchema extends z.ZodTypeAny = z.ZodUnknown> {
   // ============================================================================
 
   async #handleMessageFailure(
-    storedMessage: StoredMessage<z.infer<TPayloadSchema>>,
+    storedMessage: StoredMessage<inferZodSchemaOutput<TPayloadSchema>>,
     queueId: string,
     queueKey: string,
     queueItemsKey: string,
@@ -1455,7 +1464,7 @@ export class FairQueue<TPayloadSchema extends z.ZodTypeAny = z.ZodUnknown> {
   }
 
   async #moveToDeadLetterQueue(
-    storedMessage: StoredMessage<z.infer<TPayloadSchema>>,
+    storedMessage: StoredMessage<inferZodSchemaOutput<TPayloadSchema>>,
     errorMessage?: string
   ): Promise<void> {
     if (!this.deadLetterQueueEnabled) {
@@ -1468,7 +1477,7 @@ export class FairQueue<TPayloadSchema extends z.ZodTypeAny = z.ZodUnknown> {
     const dlqDataKey = this.keys.deadLetterQueueDataKey(storedMessage.tenantId);
     const _shardId = this.masterQueue.getShardForQueue(storedMessage.queueId);
 
-    const dlqMessage: DeadLetterMessage<z.infer<TPayloadSchema>> = {
+    const dlqMessage: DeadLetterMessage<inferZodSchemaOutput<TPayloadSchema>> = {
       id: storedMessage.id,
       queueId: storedMessage.queueId,
       tenantId: storedMessage.tenantId,
diff --git a/packages/redis-worker/src/fair-queue/tests/fairQueue.test.ts b/packages/redis-worker/src/fair-queue/tests/fairQueue.test.ts
index 5ae1f390f9f..9e7c8c6834d 100644
--- a/packages/redis-worker/src/fair-queue/tests/fairQueue.test.ts
+++ b/packages/redis-worker/src/fair-queue/tests/fairQueue.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, vi } from "vitest";
 import { redisTest } from "@internal/testcontainers";
-import { z } from "zod";
+import { z } from "zod/v4";
 import {
   FairQueue,
   DefaultFairQueueKeyProducer,
diff --git a/packages/redis-worker/src/fair-queue/tests/raceConditions.test.ts b/packages/redis-worker/src/fair-queue/tests/raceConditions.test.ts
index a497e2d738d..c6c8e2d5a6a 100644
--- a/packages/redis-worker/src/fair-queue/tests/raceConditions.test.ts
+++ b/packages/redis-worker/src/fair-queue/tests/raceConditions.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, vi } from "vitest";
 import { redisTest } from "@internal/testcontainers";
-import { z } from "zod";
+import { z } from "zod/v4";
 import {
   FairQueue,
   DefaultFairQueueKeyProducer,
diff --git a/packages/redis-worker/src/fair-queue/tests/tenantDispatch.test.ts b/packages/redis-worker/src/fair-queue/tests/tenantDispatch.test.ts
index 5f02ac331f5..e03e0b31ad6 100644
--- a/packages/redis-worker/src/fair-queue/tests/tenantDispatch.test.ts
+++ b/packages/redis-worker/src/fair-queue/tests/tenantDispatch.test.ts
@@ -1,7 +1,7 @@
 import { describe, expect } from "vitest";
 import { redisTest } from "@internal/testcontainers";
 import { createRedisClient } from "@internal/redis";
-import { z } from "zod";
+import { z } from "zod/v4";
 import {
   FairQueue,
   DefaultFairQueueKeyProducer,
diff --git a/packages/redis-worker/src/fair-queue/types.ts b/packages/redis-worker/src/fair-queue/types.ts
index 3bc56b599fa..098c1116080 100644
--- a/packages/redis-worker/src/fair-queue/types.ts
+++ b/packages/redis-worker/src/fair-queue/types.ts
@@ -1,7 +1,8 @@
 import type { RedisOptions } from "@internal/redis";
 import type { Logger } from "@trigger.dev/core/logger";
+import type { AnyZodSchema, inferZodSchemaOutput } from "@trigger.dev/core/v3";
 import type { Tracer, Meter } from "@internal/tracing";
-import type { z } from "zod";
+import type { z } from "zod/v4";
 import type { RetryStrategy } from "./retry.js";
 
 // ============================================================================
@@ -371,7 +372,7 @@ export interface CooloffOptions {
  *
  * @typeParam TPayloadSchema - Zod schema for message payload validation
  */
-export interface FairQueueOptions<TPayloadSchema extends z.ZodTypeAny = z.ZodUnknown> {
+export interface FairQueueOptions<TPayloadSchema extends AnyZodSchema = z.ZodUnknown> {
   /** Redis connection options */
   redis: RedisOptions;
 
@@ -400,7 +401,7 @@ export interface FairQueueOptions<TPayloadSchema extends z.ZodTypeAny = z.ZodUnk
    * Worker queue configuration.
    * FairQueue routes messages to worker queues; external consumers handle consumption.
    */
-  workerQueue: WorkerQueueOptions<z.infer<TPayloadSchema>>;
+  workerQueue: WorkerQueueOptions<inferZodSchemaOutput<TPayloadSchema>>;
 
   // Retry and DLQ
   /** Retry and dead letter queue configuration */
diff --git a/packages/redis-worker/src/mollifier/schemas.ts b/packages/redis-worker/src/mollifier/schemas.ts
index db75ed6e452..4d3b77a7b11 100644
--- a/packages/redis-worker/src/mollifier/schemas.ts
+++ b/packages/redis-worker/src/mollifier/schemas.ts
@@ -1,4 +1,4 @@
-import { z } from "zod";
+import { z } from "zod/v4";
 
 export const BufferEntryStatus = z.enum(["QUEUED", "DRAINING", "FAILED"]);
 export type BufferEntryStatus = z.infer<typeof BufferEntryStatus>;
@@ -56,12 +56,12 @@ export const BufferEntrySchema = z.object({
   // so an entry written by an accept Lua predating this field — or one
   // surviving across the deploy that introduced it — still parses instead
   // of being silently dropped on pop.
-  createdAtMicros: stringToInt.default("0"),
+  createdAtMicros: stringToInt.default(0),
   // Drainer-ack flag: `true` once the drainer has materialised this run
   // into PG. The hash persists for a short grace TTL after ack so direct
   // reads (retrieve, trace, etc.) still resolve while PG replica lag
   // settles. Absent on pre-ack entries.
-  materialised: stringToBool.default("false"),
+  materialised: stringToBool.default(false),
   // Denormalised pointer to the Redis idempotency lookup key (set when
   // the run was accepted with an idempotency key, empty otherwise). The
   // ack Lua reads this to DEL the lookup atomically with marking the
@@ -71,7 +71,7 @@ export const BufferEntrySchema = z.object({
   // Incremented atomically by the CAS metadata Lua. Matches the
   // semantic of `TaskRun.metadataVersion` on the PG side (which the
   // UpdateMetadataService uses for the same retry-on-conflict pattern).
-  metadataVersion: stringToInt.default("0"),
+  metadataVersion: stringToInt.default(0),
   lastError: stringToError.optional(),
 });
 
diff --git a/packages/redis-worker/src/queue.test.ts b/packages/redis-worker/src/queue.test.ts
index 8d72c2ca0b9..26b0e1ccab9 100644
--- a/packages/redis-worker/src/queue.test.ts
+++ b/packages/redis-worker/src/queue.test.ts
@@ -1,7 +1,7 @@
 import { redisTest } from "@internal/testcontainers";
 import { describe } from "node:test";
 import { expect } from "vitest";
-import { z } from "zod";
+import { z } from "zod/v4";
 import { SimpleQueue } from "./queue.js";
 import { Logger } from "@trigger.dev/core/logger";
 import { createRedisClient } from "@internal/redis";
diff --git a/packages/redis-worker/src/queue.ts b/packages/redis-worker/src/queue.ts
index becfb3813ea..0918b827f63 100644
--- a/packages/redis-worker/src/queue.ts
+++ b/packages/redis-worker/src/queue.ts
@@ -6,18 +6,18 @@ import {
   type Result,
 } from "@internal/redis";
 import { Logger } from "@trigger.dev/core/logger";
+import type { AnyZodSchema, inferZodSchemaOutput } from "@trigger.dev/core/v3";
 import { nanoid } from "nanoid";
-import type { z } from "zod";
 
 export interface MessageCatalogSchema {
-  [key: string]: z.ZodFirstPartySchemaTypes | z.ZodDiscriminatedUnion<any, any>;
+  [key: string]: AnyZodSchema;
 }
 
 export type MessageCatalogKey<TMessageCatalog extends MessageCatalogSchema> = keyof TMessageCatalog;
 export type MessageCatalogValue<
   TMessageCatalog extends MessageCatalogSchema,
   TKey extends MessageCatalogKey<TMessageCatalog>,
-> = z.infer<TMessageCatalog[TKey]>;
+> = inferZodSchemaOutput<TMessageCatalog[TKey]>;
 
 export type AnyMessageCatalog = MessageCatalogSchema;
 export type QueueItem<TMessageCatalog extends MessageCatalogSchema> = {
@@ -217,6 +217,7 @@ export class SimpleQueue<TMessageCatalog extends MessageCatalogSchema> {
           continue;
         }
 
+        // zod v4 narrows the generic schema union here; cast to public ZodType (has safeParse in v3 & v4)
         const validatedItem = schema.safeParse(parsedItem.item);
 
         if (!validatedItem.success) {
@@ -236,7 +237,7 @@ export class SimpleQueue<TMessageCatalog extends MessageCatalogSchema> {
         dequeuedItems.push({
           id,
           job: parsedItem.job,
-          item: validatedItem.data,
+          item: validatedItem.data as QueueItem<TMessageCatalog>["item"],
           visibilityTimeoutMs,
           attempt: parsedItem.attempt ?? 0,
           timestamp,
diff --git a/packages/redis-worker/src/worker.test.ts b/packages/redis-worker/src/worker.test.ts
index f5659f3795b..10f373b3c79 100644
--- a/packages/redis-worker/src/worker.test.ts
+++ b/packages/redis-worker/src/worker.test.ts
@@ -2,7 +2,7 @@ import { isolatedRedisTest as redisTest } from "@internal/testcontainers";
 import { Logger } from "@trigger.dev/core/logger";
 import { describe } from "node:test";
 import { expect } from "vitest";
-import { z } from "zod";
+import { z } from "zod/v4";
 import { Worker } from "./worker.js";
 import { createRedisClient } from "@internal/redis";
 
diff --git a/packages/redis-worker/src/worker.ts b/packages/redis-worker/src/worker.ts
index b9240acaa63..dc4fe092f26 100644
--- a/packages/redis-worker/src/worker.ts
+++ b/packages/redis-worker/src/worker.ts
@@ -12,12 +12,16 @@ import {
   ValueType,
 } from "@internal/tracing";
 import { Logger } from "@trigger.dev/core/logger";
-import { calculateNextRetryDelay } from "@trigger.dev/core/v3";
+import {
+  calculateNextRetryDelay,
+  type AnyZodSchema,
+  type inferZodSchemaOutput,
+} from "@trigger.dev/core/v3";
 import { type RetryOptions } from "@trigger.dev/core/v3/schemas";
 import { shutdownManager } from "@trigger.dev/core/v3/serverOnly";
 import { nanoid } from "nanoid";
 import pLimit from "p-limit";
-import { z } from "zod";
+import { z } from "zod/v4";
 import { type AnyQueueItem, SimpleQueue } from "./queue.js";
 import { parseExpression } from "cron-parser";
 
@@ -36,7 +40,7 @@ export type BatchConfig = {
 
 export type WorkerCatalog = {
   [key: string]: {
-    schema: z.ZodFirstPartySchemaTypes | z.ZodDiscriminatedUnion<any, any>;
+    schema: AnyZodSchema;
     visibilityTimeoutMs: number;
     retry?: RetryOptions;
     cron?: string;
@@ -56,7 +60,7 @@ type QueueCatalogFromWorkerCatalog<Catalog extends WorkerCatalog> = {
 
 export type JobHandlerParams<Catalog extends WorkerCatalog, K extends keyof Catalog> = {
   id: string;
-  payload: z.infer<Catalog[K]["schema"]>;
+  payload: inferZodSchemaOutput<Catalog[K]["schema"]>;
   visibilityTimeoutMs: number;
   attempt: number;
   deduplicationKey?: string;
@@ -311,7 +315,7 @@ class Worker<TCatalog extends WorkerCatalog> {
   }: {
     id?: string;
     job: K;
-    payload: z.infer<TCatalog[K]["schema"]>;
+    payload: inferZodSchemaOutput<TCatalog[K]["schema"]>;
     visibilityTimeoutMs?: number;
     availableAt?: Date;
     cancellationKey?: string;
@@ -373,7 +377,7 @@ class Worker<TCatalog extends WorkerCatalog> {
   }: {
     id: string;
     job: K;
-    payload: z.infer<TCatalog[K]["schema"]>;
+    payload: inferZodSchemaOutput<TCatalog[K]["schema"]>;
     visibilityTimeoutMs?: number;
     availableAt?: Date;
   }) {
@@ -1088,11 +1092,13 @@ class Worker<TCatalog extends WorkerCatalog> {
     const enqueued = await this.enqueueOnce({
       id: identifier,
       job,
+      // job is a runtime string here, so K widens and the payload can't match a
+      // single catalog entry statically; the shape is correct for the cron job.
       payload: {
         timestamp: scheduledAt.getTime(),
         lastTimestamp: lastTimestamp?.getTime(),
         cron,
-      },
+      } as inferZodSchemaOutput<TCatalog[string]["schema"]>,
       availableAt,
     });
 
diff --git a/packages/schema-to-json/package.json b/packages/schema-to-json/package.json
index 0a590345abc..795dfc51651 100644
--- a/packages/schema-to-json/package.json
+++ b/packages/schema-to-json/package.json
@@ -42,9 +42,9 @@
   },
   "dependencies": {
     "@trigger.dev/core": "workspace:*",
-    "zod-to-json-schema": "^3.24.0",
+    "zod-to-json-schema": "^3.25.0",
     "@sodaru/yup-to-json-schema": "^2",
-    "zod": "3.25.76",
+    "zod": "^3.25.76 || ^4.0.0",
     "effect": "^3"
   },
   "devDependencies": {
@@ -59,6 +59,7 @@
     "@arethetypeswrong/cli": "^0.18.5"
   },
   "peerDependencies": {
+    "zod": "^3.25.76 || ^4.0.0",
     "arktype": ">=2.0.0",
     "runtypes": ">=5.0.0",
     "superstruct": ">=0.14.2",
diff --git a/packages/schema-to-json/src/index.ts b/packages/schema-to-json/src/index.ts
index a02eef07aa3..ebaf45c7348 100644
--- a/packages/schema-to-json/src/index.ts
+++ b/packages/schema-to-json/src/index.ts
@@ -1,7 +1,7 @@
 // Import JSONSchema from core to ensure compatibility
 import type { JSONSchema } from "@trigger.dev/core/v3";
 import { zodToJsonSchema } from "zod-to-json-schema";
-import * as z4 from "zod/v4";
+import * as z4 from "zod/v4/core";
 import { convertSchema } from "@sodaru/yup-to-json-schema";
 import { JSONSchema as EffectJSONSchema } from "effect";
 
@@ -41,28 +41,32 @@ export function schemaToJsonSchema(
   schema: Schema,
   options?: ConversionOptions
 ): ConversionResult | undefined {
+  if (schema === null || (typeof schema !== "object" && typeof schema !== "function")) {
+    return undefined;
+  }
+
   const parser = schema as any;
 
-  // Check if schema has a built-in toJsonSchema method (e.g., ArkType, Zod 4)
-  if (typeof parser.toJsonSchema === "function") {
-    try {
-      const jsonSchema = parser.toJsonSchema();
+  if (isZodSchema(parser)) {
+    const jsonSchema = convertZodSchema(parser, options);
 
+    if (jsonSchema) {
       return {
-        jsonSchema,
+        jsonSchema: jsonSchema,
       };
-    } catch (_error) {
-      // If toJsonSchema fails, continue to other checks
     }
   }
 
-  if (isZodSchema(parser)) {
-    const jsonSchema = convertZodSchema(parser, options);
+  // Check if schema has a built-in toJsonSchema method (e.g., ArkType)
+  if (typeof parser.toJsonSchema === "function") {
+    try {
+      const jsonSchema = parser.toJsonSchema();
 
-    if (jsonSchema) {
       return {
-        jsonSchema: jsonSchema,
+        jsonSchema,
       };
+    } catch (_error) {
+      // If toJsonSchema fails, continue to other checks
     }
   }
 
@@ -111,11 +115,18 @@ export function isZodSchema(schema: any): boolean {
 }
 
 function isZod3Schema(schema: any): boolean {
-  return "_def" in schema && "parse" in schema && "parseAsync" in schema && "safeParse" in schema;
+  return (
+    typeof schema === "object" &&
+    schema !== null &&
+    "_def" in schema &&
+    "parse" in schema &&
+    "parseAsync" in schema &&
+    "safeParse" in schema
+  );
 }
 
 function isZod4Schema(schema: any): boolean {
-  return "_zod" in schema;
+  return typeof schema === "object" && schema !== null && "_zod" in schema;
 }
 
 function convertZodSchema(schema: any, options?: ConversionOptions): JSONSchema | undefined {
diff --git a/packages/schema-to-json/tests/index.test.ts b/packages/schema-to-json/tests/index.test.ts
index b266a42b3b0..a886085588f 100644
--- a/packages/schema-to-json/tests/index.test.ts
+++ b/packages/schema-to-json/tests/index.test.ts
@@ -265,6 +265,7 @@ describe("canConvertSchema", () => {
   });
 
   it("should return false for unsupported schemas", () => {
+    expect(canConvertSchema(null)).toBe(false);
     expect(canConvertSchema({ notASchema: true })).toBe(false);
     expect(canConvertSchema(() => true)).toBe(false);
   });
diff --git a/packages/trigger-sdk/package.json b/packages/trigger-sdk/package.json
index 64de5ea6d96..07b5ae8b6d5 100644
--- a/packages/trigger-sdk/package.json
+++ b/packages/trigger-sdk/package.json
@@ -101,13 +101,13 @@
     "tshy": "^3.0.2",
     "tsx": "4.17.0",
     "typed-emitter": "^2.1.0",
-    "zod": "3.25.76"
+    "zod": "4.4.3"
   },
   "peerDependencies": {
     "@ai-sdk/otel": ">=1.0.0-0 <2",
     "ai": "^5.0.0 || ^6.0.0 || >=7.0.0-canary <8",
     "react": "^18.0 || ^19.0",
-    "zod": "^3.0.0 || ^4.0.0"
+    "zod": "^3.25.76 || ^4.0.0"
   },
   "peerDependenciesMeta": {
     "@ai-sdk/otel": {
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 45163c161bb..71ed63149f8 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -53,6 +53,7 @@ overrides:
   brace-expansion@>=5 <5.0.6: 5.0.6
   '@jsonhero/json-infer-types>ip-address': ^10.2.0
   '@modelcontextprotocol/sdk@>=1.26.0>express-rate-limit': ^8.6.0
+  zod: 4.4.3
 
 patchedDependencies:
   '@changesets/assemble-release-plan@5.2.4':
@@ -191,8 +192,8 @@ importers:
         specifier: ^3.8.0
         version: 3.8.1
       zod:
-        specifier: 3.25.76
-        version: 3.25.76
+        specifier: 4.4.3
+        version: 4.4.3
     devDependencies:
       '@internal/testcontainers':
         specifier: workspace:*
@@ -205,13 +206,13 @@ importers:
     dependencies:
       '@ai-sdk/anthropic':
         specifier: ^3.0.0
-        version: 3.0.84(zod@3.25.76)
+        version: 3.0.84(zod@4.4.3)
       '@ai-sdk/openai':
         specifier: ^3.0.0
-        version: 3.0.41(zod@3.25.76)
+        version: 3.0.41(zod@4.4.3)
       '@ai-sdk/react':
         specifier: ^3.0.0
-        version: 3.0.170(react@18.3.1)(zod@3.25.76)
+        version: 3.0.170(react@18.3.1)(zod@4.4.3)
       '@ariakit/react':
         specifier: ^0.4.6
         version: 0.4.6(react-dom@18.3.1(react@18.3.1))(react@18.3.1)
@@ -268,7 +269,7 @@ importers:
         version: 1.19.4(react-dom@18.3.1(react@18.3.1))(react@18.3.1)
       '@conform-to/zod':
         specifier: ^1.2.2
-        version: 1.19.4(zod@3.25.76)
+        version: 1.19.4(zod@4.4.3)
       '@depot/cli':
         specifier: 0.0.1-cli.2.80.0
         version: 0.0.1-cli.2.80.0
@@ -489,8 +490,8 @@ importers:
         specifier: workspace:*
         version: link:../../internal-packages/otlp-importer
       '@trigger.dev/platform':
-        specifier: 1.3.0
-        version: 1.3.0(zod@3.25.76)
+        specifier: 1.3.1
+        version: 1.3.1(zod@4.4.3)
       '@trigger.dev/plugins':
         specifier: workspace:*
         version: link:../../packages/plugins
@@ -526,7 +527,7 @@ importers:
         version: 1.1.3(react-dom@18.3.1(react@18.3.1))(react@18.3.1)
       ai:
         specifier: 6.0.116
-        version: 6.0.116(zod@3.25.76)
+        version: 6.0.116(zod@4.4.3)
       assert:
         specifier: ^2.1.0
         version: 2.1.0
@@ -727,7 +728,7 @@ importers:
         version: 0.3.1(@remix-run/react@2.17.5(react-dom@18.3.1(react@18.3.1))(react@18.3.1)(typescript@6.0.3))(@remix-run/server-runtime@2.17.5(typescript@6.0.3))(react@18.3.1)
       remix-utils:
         specifier: ^7.7.0
-        version: 7.7.0(@remix-run/node@2.17.5(typescript@6.0.3))(@remix-run/react@2.17.5(react-dom@18.3.1(react@18.3.1))(react@18.3.1)(typescript@6.0.3))(@remix-run/router@1.23.3(patch_hash=33e2966e9ef36aa09955cec9922c5063227b83429157a71ba226369a08627ac9))(crypto-js@4.2.0)(intl-parse-accept-language@1.0.0)(react@18.3.1)(zod@3.25.76)
+        version: 7.7.0(@remix-run/node@2.17.5(typescript@6.0.3))(@remix-run/react@2.17.5(react-dom@18.3.1(react@18.3.1))(react@18.3.1)(typescript@6.0.3))(@remix-run/router@1.23.3(patch_hash=33e2966e9ef36aa09955cec9922c5063227b83429157a71ba226369a08627ac9))(crypto-js@4.2.0)(intl-parse-accept-language@1.0.0)(react@18.3.1)(zod@4.4.3)
       semver:
         specifier: ^7.5.0
         version: 7.8.1
@@ -777,14 +778,14 @@ importers:
         specifier: 8.21.0
         version: 8.21.0(bufferutil@4.0.9)
       zod:
-        specifier: 3.25.76
-        version: 3.25.76
+        specifier: 4.4.3
+        version: 4.4.3
       zod-error:
-        specifier: 1.5.0
-        version: 1.5.0
+        specifier: 2.0.0
+        version: 2.0.0(zod@4.4.3)
       zod-validation-error:
-        specifier: ^1.5.0
-        version: 1.5.0(zod@3.25.76)
+        specifier: ^5.0.0
+        version: 5.0.0(zod@4.4.3)
     devDependencies:
       '@internal/clickhouse':
         specifier: workspace:*
@@ -899,7 +900,7 @@ importers:
         version: 0.15.18
       evalite:
         specifier: 1.0.0-beta.16
-        version: 1.0.0-beta.16(ai@6.0.116(zod@3.25.76))(better-sqlite3@11.10.0)(bufferutil@4.0.9)
+        version: 1.0.0-beta.16(ai@6.0.116(zod@4.4.3))(better-sqlite3@11.10.0)(bufferutil@4.0.9)
       npm-run-all:
         specifier: ^4.1.5
         version: 4.1.5
@@ -975,11 +976,11 @@ importers:
         specifier: workspace:*
         version: link:../../packages/core
       zod:
-        specifier: 3.25.76
-        version: 3.25.76
+        specifier: 4.4.3
+        version: 4.4.3
       zod-error:
-        specifier: 1.5.0
-        version: 1.5.0
+        specifier: 2.0.0
+        version: 2.0.0(zod@4.4.3)
     devDependencies:
       '@internal/testcontainers':
         specifier: workspace:*
@@ -991,8 +992,8 @@ importers:
   internal-packages/compute:
     dependencies:
       zod:
-        specifier: 3.25.76
-        version: 3.25.76
+        specifier: 4.4.3
+        version: 4.4.3
     devDependencies:
       rimraf:
         specifier: 6.0.1
@@ -1002,7 +1003,7 @@ importers:
     dependencies:
       '@ai-sdk/anthropic':
         specifier: ^3.0.0
-        version: 3.0.84(zod@3.25.76)
+        version: 3.0.84(zod@4.4.3)
       '@internal/dashboard-agent-db':
         specifier: workspace:*
         version: link:../dashboard-agent-db
@@ -1011,10 +1012,10 @@ importers:
         version: link:../../packages/trigger-sdk
       ai:
         specifier: 6.0.116
-        version: 6.0.116(zod@3.25.76)
+        version: 6.0.116(zod@4.4.3)
       zod:
-        specifier: 3.25.76
-        version: 3.25.76
+        specifier: 4.4.3
+        version: 4.4.3
     devDependencies:
       '@ai-sdk/provider':
         specifier: 3.0.8
@@ -1088,8 +1089,8 @@ importers:
         specifier: ^1.2.0
         version: 1.3.1
       zod:
-        specifier: 3.25.76
-        version: 3.25.76
+        specifier: 4.4.3
+        version: 4.4.3
     devDependencies:
       '@types/nodemailer':
         specifier: ^8.0.0
@@ -1256,8 +1257,8 @@ importers:
         specifier: ^3.0.5
         version: 3.0.5
       zod:
-        specifier: 3.25.76
-        version: 3.25.76
+        specifier: 4.4.3
+        version: 4.4.3
     devDependencies:
       '@internal/testcontainers':
         specifier: workspace:*
@@ -1334,8 +1335,8 @@ importers:
         specifier: 3.3.8
         version: 3.3.8
       zod:
-        specifier: 3.25.76
-        version: 3.25.76
+        specifier: 4.4.3
+        version: 4.4.3
     devDependencies:
       '@internal/testcontainers':
         specifier: workspace:*
@@ -1446,8 +1447,8 @@ importers:
         specifier: 0.5.0-alpha.4
         version: 0.5.0-alpha.4(patch_hash=b5d41129ddbf7c4cbb0288244b2c8d041ee0803c5102c1181c180408d3b579f4)
       zod:
-        specifier: 3.25.76
-        version: 3.25.76
+        specifier: 4.4.3
+        version: 4.4.3
     devDependencies:
       antlr4ts-cli:
         specifier: 0.5.0-alpha.4
@@ -1506,7 +1507,7 @@ importers:
         version: 0.0.1-cli.2.80.0
       '@modelcontextprotocol/sdk':
         specifier: ^1.25.2
-        version: 1.25.2(hono@4.12.25)(supports-color@10.0.0)(zod@3.25.76)
+        version: 1.25.2(hono@4.12.25)(supports-color@10.0.0)(zod@4.4.3)
       '@opentelemetry/api':
         specifier: 1.9.1
         version: 1.9.1
@@ -1685,11 +1686,11 @@ importers:
         specifier: ^8.3.0
         version: 8.3.0
       zod:
-        specifier: 3.25.76
-        version: 3.25.76
+        specifier: 4.4.3
+        version: 4.4.3
       zod-validation-error:
-        specifier: ^1.5.0
-        version: 1.5.0(zod@3.25.76)
+        specifier: ^5.0.0
+        version: 5.0.0(zod@4.4.3)
     devDependencies:
       '@epic-web/test-server':
         specifier: ^0.1.0
@@ -1845,18 +1846,15 @@ importers:
         specifier: ^0.1.3
         version: 0.1.3
       zod:
-        specifier: 3.25.76
-        version: 3.25.76
-      zod-error:
-        specifier: 1.5.0
-        version: 1.5.0
+        specifier: 4.4.3
+        version: 4.4.3
       zod-validation-error:
-        specifier: ^1.5.0
-        version: 1.5.0(zod@3.25.76)
+        specifier: ^5.0.0
+        version: 5.0.0(zod@4.4.3)
     devDependencies:
       '@ai-sdk/provider-utils':
         specifier: ^1.0.22
-        version: 1.0.22(zod@3.25.76)
+        version: 1.0.22(zod@4.4.3)
       '@arethetypeswrong/cli':
         specifier: ^0.18.5
         version: 0.18.5
@@ -1877,10 +1875,10 @@ importers:
         version: 4.0.14
       ai:
         specifier: 6.0.116
-        version: 6.0.116(zod@3.25.76)
+        version: 6.0.116(zod@4.4.3)
       ai-v7:
         specifier: npm:ai@7.0.0-canary.159
-        version: ai@7.0.0-canary.159(zod@3.25.76)
+        version: ai@7.0.0-canary.159(zod@4.4.3)
       defu:
         specifier: ^6.1.5
         version: 6.1.7
@@ -2017,8 +2015,8 @@ importers:
         specifier: ^3.0.5
         version: 3.0.5
       zod:
-        specifier: 3.25.76
-        version: 3.25.76
+        specifier: 4.4.3
+        version: 4.4.3
     devDependencies:
       '@internal/redis':
         specifier: workspace:*
@@ -2097,11 +2095,11 @@ importers:
         specifier: ^3
         version: 3.17.1
       zod:
-        specifier: 3.25.76
-        version: 3.25.76
+        specifier: 4.4.3
+        version: 4.4.3
       zod-to-json-schema:
-        specifier: ^3.24.0
-        version: 3.24.6(zod@3.25.76)
+        specifier: ^3.25.0
+        version: 3.25.1(zod@4.4.3)
     devDependencies:
       '@arethetypeswrong/cli':
         specifier: ^0.18.5
@@ -2135,7 +2133,7 @@ importers:
     dependencies:
       '@ai-sdk/otel':
         specifier: '>=1.0.0-0 <2'
-        version: 1.0.0-beta.6(zod@3.25.76)
+        version: 1.0.0-beta.6(zod@4.4.3)
       '@opentelemetry/api':
         specifier: 1.9.1
         version: 1.9.1
@@ -2193,10 +2191,10 @@ importers:
         version: 8.5.4
       ai:
         specifier: 6.0.116
-        version: 6.0.116(zod@3.25.76)
+        version: 6.0.116(zod@4.4.3)
       ai-v7:
         specifier: npm:ai@7.0.0-canary.159
-        version: ai@7.0.0-canary.159(zod@3.25.76)
+        version: ai@7.0.0-canary.159(zod@4.4.3)
       encoding:
         specifier: ^0.1.13
         version: 0.1.13
@@ -2213,8 +2211,8 @@ importers:
         specifier: ^2.1.0
         version: 2.1.0
       zod:
-        specifier: 3.25.76
-        version: 3.25.76
+        specifier: 4.4.3
+        version: 4.4.3
 
 packages:
 
@@ -2222,31 +2220,31 @@ packages:
     resolution: {integrity: sha512-BIDaHmCHs6Sr5VUsEkTbbVlAN4GWjg97X9x/IfXyviLtzsXvffui9XIcZugkAi1Ri6FnvI5T5qDGh5YLnSuzRg==}
     engines: {node: '>=18'}
     peerDependencies:
-      zod: ^3.25.76 || ^4.1.8
+      zod: 4.4.3
 
   '@ai-sdk/gateway@3.0.66':
     resolution: {integrity: sha512-SIQ0YY0iMuv+07HLsZ+bB990zUJ6S4ujORAh+Jv1V2KGNn73qQKnGO0JBk+w+Res8YqOFSycwDoWcFlQrVxS4A==}
     engines: {node: '>=18'}
     peerDependencies:
-      zod: ^3.25.76 || ^4.1.8
+      zod: 4.4.3
 
   '@ai-sdk/gateway@4.0.0-beta.30':
     resolution: {integrity: sha512-05tWxCb+3SRj5LBY37nRQ8eUdolO5QvKAfsIAUY3zAxg0jc1cBkQNSpZEVwQUR4uFm/Y5fLJ+MIa+6hkol1//A==}
     engines: {node: '>=18'}
     peerDependencies:
-      zod: ^3.25.76 || ^4.1.8
+      zod: 4.4.3
 
   '@ai-sdk/gateway@4.0.0-canary.93':
     resolution: {integrity: sha512-/d0d/DfJRmdMJJww/ihrYezgKedJhrOCsREuAuSHmd/kVzFB5p2bBuCZH3EBxKFQ8NLtPJpOR+QJxOUmDLD8PA==}
     engines: {node: '>=22'}
     peerDependencies:
-      zod: ^3.25.76 || ^4.1.8
+      zod: 4.4.3
 
   '@ai-sdk/openai@3.0.41':
     resolution: {integrity: sha512-IZ42A+FO+vuEQCVNqlnAPYQnnUpUfdJIwn1BEDOBywiEHa23fw7PahxVtlX9zm3/zMvTW4JKPzWyvAgDu+SQ2A==}
     engines: {node: '>=18'}
     peerDependencies:
-      zod: ^3.25.76 || ^4.1.8
+      zod: 4.4.3
 
   '@ai-sdk/otel@1.0.0-beta.6':
     resolution: {integrity: sha512-K5VikyO3EKQkNk77ew9oMjM8FInKF+WWar599LmP8rQ0x0iB+P/DVS+h6zQvmecxMNPtQOOyt0uDQFx/AA0DGw==}
@@ -2256,7 +2254,7 @@ packages:
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     engines: {node: '>=18'}
     peerDependencies:
-      zod: ^3.0.0
+      zod: 4.4.3
     peerDependenciesMeta:
       zod:
         optional: true
@@ -2265,19 +2263,19 @@ packages:
     resolution: {integrity: sha512-uhukHaCBvqkwBHkT8C2PrnqKTCoLn3pdHXqtcR9I8ErH+flbzgW4o7VHSNIup9LRu+WBvZIZDQLsx6rwl2tiOA==}
     engines: {node: '>=18'}
     peerDependencies:
-      zod: ^3.25.76 || ^4.1.8
+      zod: 4.4.3
 
   '@ai-sdk/provider-utils@5.0.0-beta.9':
     resolution: {integrity: sha512-Ku/S1TV8ibqlweKQHa22eWT9QvKqR4hkl7KMJ0k7kw64Q7XObh12fJUnK4Mh8q+IR5ZeQGm95SLtx++d7FC6XA==}
     engines: {node: '>=18'}
     peerDependencies:
-      zod: ^3.25.76 || ^4.1.8
+      zod: 4.4.3
 
   '@ai-sdk/provider-utils@5.0.0-canary.44':
     resolution: {integrity: sha512-3h7gp8MEwXACWsW8ZPjzio53ynKq0jTNp4Hwr0BWdychMFzmkRRWyvijhg56JWxye16FU92SqQnfBoe2PN4I2A==}
     engines: {node: '>=22'}
     peerDependencies:
-      zod: ^3.25.76 || ^4.1.8
+      zod: 4.4.3
 
   '@ai-sdk/provider@0.0.26':
     resolution: {integrity: sha512-dQkfBDs2lTYpKM8389oopPdQgIU007GQyCbuPPrV+K6MtSII3HBfE0stUIMXUb44L+LK1t6GXPP7wjSzjO6uKg==}
@@ -3149,7 +3147,7 @@ packages:
   '@conform-to/zod@1.19.4':
     resolution: {integrity: sha512-g80QtotXLcXWCF86Xou/VpI6i+NBOQxYgLS9YCQYrgV27yilZFJYpgWWBsA8YwodmJVBIYm9RawJba7WnUoddA==}
     peerDependencies:
-      zod: ^3.21.0 || ^4.0.0
+      zod: 4.4.3
 
   '@connectrpc/connect-node@1.4.0':
     resolution: {integrity: sha512-0ANnrr6SvsjevsWEgdzHy7BaHkluZyS6s4xNoVt7RBHFR5V/kT9lPokoIbYUOU9JHzdRgTaS3x5595mwUsu15g==}
@@ -4607,7 +4605,7 @@ packages:
     engines: {node: '>=18'}
     peerDependencies:
       '@cfworker/json-schema': ^4.1.1
-      zod: ^3.25 || ^4.0
+      zod: 4.4.3
     peerDependenciesMeta:
       '@cfworker/json-schema':
         optional: true
@@ -4617,7 +4615,7 @@ packages:
     engines: {node: '>=18'}
     peerDependencies:
       '@cfworker/json-schema': ^4.1.1
-      zod: ^3.25 || ^4.0
+      zod: 4.4.3
     peerDependenciesMeta:
       '@cfworker/json-schema':
         optional: true
@@ -7727,10 +7725,10 @@ packages:
       react: 18.3.1
       react-dom: 18.3.1
 
-  '@trigger.dev/platform@1.3.0':
-    resolution: {integrity: sha512-DIJ5Sy4X5XKSHQdYA3GImkb0jdE9I/HTRRRB3c9CFuXjGzhK3rJkEzjIEbaNRjk6yAev67EVTWY8P+D+khorUw==}
+  '@trigger.dev/platform@1.3.1':
+    resolution: {integrity: sha512-eCmoeilJyat6APofjHnyiJzOYobHbukbmexDpZVbQlqAkJaXKsK/f07Ijuw8Cyx3kTj8Hc24fj2vMHFPwcE9VA==}
     peerDependencies:
-      zod: ^3.25.0 || ^4.0.0
+      zod: 4.4.3
 
   '@tybys/wasm-util@0.10.3':
     resolution: {integrity: sha512-F3fo1MYrRJYL3zER0OUOmkutjr1Vp23m7OsSgp7nq4SP6OqX6C/56XFIPAl5bt3zaBRjmW7SGz3u/6LwFpYcOg==}
@@ -8406,19 +8404,19 @@ packages:
     resolution: {integrity: sha512-7yM+cTmyRLeNIXwt4Vj+mrrJgVQ9RMIW5WO0ydoLoYkewIvsMcvUmqS4j2RJTUXaF1HphwmSKUMQ/HypNRGOmA==}
     engines: {node: '>=18'}
     peerDependencies:
-      zod: ^3.25.76 || ^4.1.8
+      zod: 4.4.3
 
   ai@7.0.0-beta.60:
     resolution: {integrity: sha512-grSKE/9kQtElLCnrhwriTLwXlV+5W8Ljco2KzVc5cY9egK1zwSwVyFQo3L3Al+WVxwvVT6fQjLyEdQpqJHLTrA==}
     engines: {node: '>=18'}
     peerDependencies:
-      zod: ^3.25.76 || ^4.1.8
+      zod: 4.4.3
 
   ai@7.0.0-canary.159:
     resolution: {integrity: sha512-9z8OkZdrISDjS3bguQ/mCYsthmr7mNbB1hTa8cRg8aAp31r1HCxVFqmc+ZXTA0FqhGb8aW46UUcjUuJcwxg5Mw==}
     engines: {node: '>=22'}
     peerDependencies:
-      zod: ^3.25.76 || ^4.1.8
+      zod: 4.4.3
 
   ajv-formats@2.1.1:
     resolution: {integrity: sha512-Wx0Kx52hxE7C18hkMEggYlEifqWZtYaRgouJor+WMdPnQyEK13vgEWyVNup7SoeeoLMsr4kf5h6dOW11I15MUA==}
@@ -12613,7 +12611,7 @@ packages:
     hasBin: true
     peerDependencies:
       ws: 8.21.0
-      zod: ^3.23.8
+      zod: 4.4.3
     peerDependenciesMeta:
       ws:
         optional: true
@@ -13769,7 +13767,7 @@ packages:
       intl-parse-accept-language: ^1.0.0
       is-ip: ^5.0.1
       react: 18.3.1
-      zod: ^3.22.4
+      zod: 4.4.3
     peerDependenciesMeta:
       '@remix-run/cloudflare':
         optional: true
@@ -15597,37 +15595,31 @@ packages:
     resolution: {integrity: sha512-zK7YHHz4ZXpW89AHXUPbQVGKI7uvkd3hzusTdotCg1UxyaVtg0zFJSTfW/Dq5f7OBBVnq6cZIaC8Ti4hb6dtCA==}
     engines: {node: '>= 14'}
 
-  zod-error@1.5.0:
-    resolution: {integrity: sha512-zzopKZ/skI9iXpqCEPj+iLCKl9b88E43ehcU+sbRoHuwGd9F1IDVGQ70TyO6kmfiRL1g4IXkjsXK+g1gLYl4WQ==}
+  zod-error@2.0.0:
+    resolution: {integrity: sha512-ivSoPm7h5SEGG8GUvQ7YTwrnEx36qNmUIU5hSIGcqcdl7+ZFoTrYXAdQEs3KP/rkihrrR9REEdOeGU+fWdMoNw==}
+    peerDependencies:
+      zod: 4.4.3
 
   zod-to-json-schema@3.24.5:
     resolution: {integrity: sha512-/AuWwMP+YqiPbsJx5D6TfgRTc4kTLjsh5SOcd4bLsfUg2RcEXrFMJl1DGgdHy2aCfsIA/cr/1JM0xcB2GZji8g==}
     peerDependencies:
-      zod: ^3.24.1
-
-  zod-to-json-schema@3.24.6:
-    resolution: {integrity: sha512-h/z3PKvcTcTetyjl1fkj79MHNEjm+HpD6NXheWjzOekY7kV+lwDYnHw+ivHkijnCSMz1yJaWBD9vu/Fcmk+vEg==}
-    peerDependencies:
-      zod: ^3.24.1
+      zod: 4.4.3
 
   zod-to-json-schema@3.25.0:
     resolution: {integrity: sha512-HvWtU2UG41LALjajJrML6uQejQhNJx+JBO9IflpSja4R03iNWfKXrj6W2h7ljuLyc1nKS+9yDyL/9tD1U/yBnQ==}
     peerDependencies:
-      zod: ^3.25 || ^4
+      zod: 4.4.3
 
   zod-to-json-schema@3.25.1:
     resolution: {integrity: sha512-pM/SU9d3YAggzi6MtR4h7ruuQlqKtad8e9S0fmxcMi+ueAK5Korys/aWcV9LIIHTVbj01NdzxcnXSN+O74ZIVA==}
     peerDependencies:
-      zod: ^3.25 || ^4
+      zod: 4.4.3
 
-  zod-validation-error@1.5.0:
-    resolution: {integrity: sha512-/7eFkAI4qV0tcxMBB/3+d2c1P6jzzZYdYSlBuAklzMuCrJu5bzJfHS0yVAS87dRHVlhftd6RFJDIvv03JgkSbw==}
-    engines: {node: '>=16.0.0'}
+  zod-validation-error@5.0.0:
+    resolution: {integrity: sha512-hmk+pkyKq7Q71PiWVSDUc3VfpzpvcRHZ3QPw9yEMVvmtCekaMeOHnbr3WbxfrgEnQTv6haGP4cmv0Ojmihzsxw==}
+    engines: {node: '>=18.0.0'}
     peerDependencies:
-      zod: ^3.18.0
-
-  zod@3.25.76:
-    resolution: {integrity: sha512-gzUt/qt81nXsFGKIFcC3YnfEAx5NkunCfnDlvuBSSFS02bcXu4Lmea0AFIUwbLWxWPx3d9p8S5QoaujKcNQxcQ==}
+      zod: 4.4.3
 
   zod@4.4.3:
     resolution: {integrity: sha512-ytENFjIJFl2UwYglde2jchW2Hwm4GJFLDiSXWdTrJQBIN9Fcyp7n4DhxJEiWNAJMV1/BqWfW/kkg71UDcHJyTQ==}
@@ -15637,77 +15629,77 @@ packages:
 
 snapshots:
 
-  '@ai-sdk/anthropic@3.0.84(zod@3.25.76)':
+  '@ai-sdk/anthropic@3.0.84(zod@4.4.3)':
     dependencies:
       '@ai-sdk/provider': 3.0.10
-      '@ai-sdk/provider-utils': 4.0.29(zod@3.25.76)
-      zod: 3.25.76
+      '@ai-sdk/provider-utils': 4.0.29(zod@4.4.3)
+      zod: 4.4.3
 
-  '@ai-sdk/gateway@3.0.66(zod@3.25.76)':
+  '@ai-sdk/gateway@3.0.66(zod@4.4.3)':
     dependencies:
       '@ai-sdk/provider': 3.0.8
-      '@ai-sdk/provider-utils': 4.0.29(zod@3.25.76)
+      '@ai-sdk/provider-utils': 4.0.29(zod@4.4.3)
       '@vercel/oidc': 3.1.0
-      zod: 3.25.76
+      zod: 4.4.3
 
-  '@ai-sdk/gateway@4.0.0-beta.30(zod@3.25.76)':
+  '@ai-sdk/gateway@4.0.0-beta.30(zod@4.4.3)':
     dependencies:
       '@ai-sdk/provider': 4.0.0-beta.5
-      '@ai-sdk/provider-utils': 5.0.0-beta.9(zod@3.25.76)
+      '@ai-sdk/provider-utils': 5.0.0-beta.9(zod@4.4.3)
       '@vercel/oidc': 3.2.0
-      zod: 3.25.76
+      zod: 4.4.3
 
-  '@ai-sdk/gateway@4.0.0-canary.93(zod@3.25.76)':
+  '@ai-sdk/gateway@4.0.0-canary.93(zod@4.4.3)':
     dependencies:
       '@ai-sdk/provider': 4.0.0-canary.17
-      '@ai-sdk/provider-utils': 5.0.0-canary.44(zod@3.25.76)
+      '@ai-sdk/provider-utils': 5.0.0-canary.44(zod@4.4.3)
       '@vercel/oidc': 3.2.0
-      zod: 3.25.76
+      zod: 4.4.3
 
-  '@ai-sdk/openai@3.0.41(zod@3.25.76)':
+  '@ai-sdk/openai@3.0.41(zod@4.4.3)':
     dependencies:
       '@ai-sdk/provider': 3.0.8
-      '@ai-sdk/provider-utils': 4.0.29(zod@3.25.76)
-      zod: 3.25.76
+      '@ai-sdk/provider-utils': 4.0.29(zod@4.4.3)
+      zod: 4.4.3
 
-  '@ai-sdk/otel@1.0.0-beta.6(zod@3.25.76)':
+  '@ai-sdk/otel@1.0.0-beta.6(zod@4.4.3)':
     dependencies:
       '@ai-sdk/provider': 4.0.0-beta.5
       '@opentelemetry/api': 1.9.0
-      ai: 7.0.0-beta.60(zod@3.25.76)
+      ai: 7.0.0-beta.60(zod@4.4.3)
     transitivePeerDependencies:
       - zod
 
-  '@ai-sdk/provider-utils@1.0.22(zod@3.25.76)':
+  '@ai-sdk/provider-utils@1.0.22(zod@4.4.3)':
     dependencies:
       '@ai-sdk/provider': 0.0.26
       eventsource-parser: 1.1.2
       nanoid: 3.3.8
       secure-json-parse: 2.7.0
     optionalDependencies:
-      zod: 3.25.76
+      zod: 4.4.3
 
-  '@ai-sdk/provider-utils@4.0.29(zod@3.25.76)':
+  '@ai-sdk/provider-utils@4.0.29(zod@4.4.3)':
     dependencies:
       '@ai-sdk/provider': 3.0.10
       '@standard-schema/spec': 1.1.0
       eventsource-parser: 3.1.0
-      zod: 3.25.76
+      zod: 4.4.3
 
-  '@ai-sdk/provider-utils@5.0.0-beta.9(zod@3.25.76)':
+  '@ai-sdk/provider-utils@5.0.0-beta.9(zod@4.4.3)':
     dependencies:
       '@ai-sdk/provider': 4.0.0-beta.5
       '@standard-schema/spec': 1.1.0
       eventsource-parser: 3.1.0
-      zod: 3.25.76
+      zod: 4.4.3
 
-  '@ai-sdk/provider-utils@5.0.0-canary.44(zod@3.25.76)':
+  '@ai-sdk/provider-utils@5.0.0-canary.44(zod@4.4.3)':
     dependencies:
       '@ai-sdk/provider': 4.0.0-canary.17
       '@standard-schema/spec': 1.1.0
       '@workflow/serde': 4.1.0
       eventsource-parser: 3.1.0
-      zod: 3.25.76
+      zod: 4.4.3
 
   '@ai-sdk/provider@0.0.26':
     dependencies:
@@ -15729,10 +15721,10 @@ snapshots:
     dependencies:
       json-schema: 0.4.0
 
-  '@ai-sdk/react@3.0.170(react@18.3.1)(zod@3.25.76)':
+  '@ai-sdk/react@3.0.170(react@18.3.1)(zod@4.4.3)':
     dependencies:
-      '@ai-sdk/provider-utils': 4.0.29(zod@3.25.76)
-      ai: 6.0.116(zod@3.25.76)
+      '@ai-sdk/provider-utils': 4.0.29(zod@4.4.3)
+      ai: 6.0.116(zod@4.4.3)
       react: 18.3.1
       swr: 2.2.5(react@18.3.1)
       throttleit: 2.1.0
@@ -17821,10 +17813,10 @@ snapshots:
       react: 18.3.1
       react-dom: 18.3.1(react@18.3.1)
 
-  '@conform-to/zod@1.19.4(zod@3.25.76)':
+  '@conform-to/zod@1.19.4(zod@4.4.3)':
     dependencies:
       '@conform-to/dom': 1.19.4
-      zod: 3.25.76
+      zod: 4.4.3
 
   '@connectrpc/connect-node@1.4.0(@bufbuild/protobuf@1.10.0)(@connectrpc/connect@1.4.0(@bufbuild/protobuf@1.10.0))':
     dependencies:
@@ -18899,7 +18891,7 @@ snapshots:
 
   '@microsoft/fetch-event-source@2.0.1': {}
 
-  '@modelcontextprotocol/sdk@1.25.2(hono@4.12.25)(supports-color@10.0.0)(zod@3.25.76)':
+  '@modelcontextprotocol/sdk@1.25.2(hono@4.12.25)(supports-color@10.0.0)(zod@4.4.3)':
     dependencies:
       '@hono/node-server': 1.19.9(hono@4.12.25)
       ajv: 8.18.0
@@ -18915,13 +18907,13 @@ snapshots:
       json-schema-typed: 8.0.2
       pkce-challenge: 5.0.0
       raw-body: 3.0.0
-      zod: 3.25.76
-      zod-to-json-schema: 3.25.0(zod@3.25.76)
+      zod: 4.4.3
+      zod-to-json-schema: 3.25.0(zod@4.4.3)
     transitivePeerDependencies:
       - hono
       - supports-color
 
-  '@modelcontextprotocol/sdk@1.26.0(zod@3.25.76)':
+  '@modelcontextprotocol/sdk@1.26.0(zod@4.4.3)':
     dependencies:
       '@hono/node-server': 1.19.9(hono@4.12.25)
       ajv: 8.18.0
@@ -18938,8 +18930,8 @@ snapshots:
       json-schema-typed: 8.0.2
       pkce-challenge: 5.0.0
       raw-body: 3.0.0
-      zod: 3.25.76
-      zod-to-json-schema: 3.25.1(zod@3.25.76)
+      zod: 4.4.3
+      zod-to-json-schema: 3.25.1(zod@4.4.3)
     transitivePeerDependencies:
       - supports-color
 
@@ -22368,9 +22360,9 @@ snapshots:
       react: 18.3.1
       react-dom: 18.3.1(react@18.3.1)
 
-  '@trigger.dev/platform@1.3.0(zod@3.25.76)':
+  '@trigger.dev/platform@1.3.1(zod@4.4.3)':
     dependencies:
-      zod: 3.25.76
+      zod: 4.4.3
 
   '@tybys/wasm-util@0.10.3':
     dependencies:
@@ -22889,7 +22881,7 @@ snapshots:
 
   '@unkey/error@0.2.0':
     dependencies:
-      zod: 3.25.76
+      zod: 4.4.3
 
   '@upsetjs/venn.js@2.0.0':
     optionalDependencies:
@@ -22961,8 +22953,8 @@ snapshots:
 
   '@vercel/sdk@1.19.1':
     dependencies:
-      '@modelcontextprotocol/sdk': 1.26.0(zod@3.25.76)
-      zod: 3.25.76
+      '@modelcontextprotocol/sdk': 1.26.0(zod@4.4.3)
+      zod: 4.4.3
     transitivePeerDependencies:
       - '@cfworker/json-schema'
       - supports-color
@@ -23197,27 +23189,27 @@ snapshots:
 
   ahocorasick@1.0.2: {}
 
-  ai@6.0.116(zod@3.25.76):
+  ai@6.0.116(zod@4.4.3):
     dependencies:
-      '@ai-sdk/gateway': 3.0.66(zod@3.25.76)
+      '@ai-sdk/gateway': 3.0.66(zod@4.4.3)
       '@ai-sdk/provider': 3.0.8
-      '@ai-sdk/provider-utils': 4.0.29(zod@3.25.76)
+      '@ai-sdk/provider-utils': 4.0.29(zod@4.4.3)
       '@opentelemetry/api': 1.9.0
-      zod: 3.25.76
+      zod: 4.4.3
 
-  ai@7.0.0-beta.60(zod@3.25.76):
+  ai@7.0.0-beta.60(zod@4.4.3):
     dependencies:
-      '@ai-sdk/gateway': 4.0.0-beta.30(zod@3.25.76)
+      '@ai-sdk/gateway': 4.0.0-beta.30(zod@4.4.3)
       '@ai-sdk/provider': 4.0.0-beta.5
-      '@ai-sdk/provider-utils': 5.0.0-beta.9(zod@3.25.76)
-      zod: 3.25.76
+      '@ai-sdk/provider-utils': 5.0.0-beta.9(zod@4.4.3)
+      zod: 4.4.3
 
-  ai@7.0.0-canary.159(zod@3.25.76):
+  ai@7.0.0-canary.159(zod@4.4.3):
     dependencies:
-      '@ai-sdk/gateway': 4.0.0-canary.93(zod@3.25.76)
+      '@ai-sdk/gateway': 4.0.0-canary.93(zod@4.4.3)
       '@ai-sdk/provider': 4.0.0-canary.17
-      '@ai-sdk/provider-utils': 5.0.0-canary.44(zod@3.25.76)
-      zod: 3.25.76
+      '@ai-sdk/provider-utils': 5.0.0-canary.44(zod@4.4.3)
+      zod: 4.4.3
 
   ajv-formats@2.1.1(ajv@8.20.0):
     optionalDependencies:
@@ -23404,9 +23396,9 @@ snapshots:
       js-yaml: 4.1.1
       linear-sum-assignment: 1.0.7
       mustache: 4.2.0
-      openai: 4.97.0(encoding@0.1.13)(ws@8.21.0(bufferutil@4.0.9))(zod@3.25.76)
-      zod: 3.25.76
-      zod-to-json-schema: 3.24.5(zod@3.25.76)
+      openai: 4.97.0(encoding@0.1.13)(ws@8.21.0(bufferutil@4.0.9))(zod@4.4.3)
+      zod: 4.4.3
+      zod-to-json-schema: 3.24.5(zod@4.4.3)
     transitivePeerDependencies:
       - encoding
       - ws
@@ -25307,7 +25299,7 @@ snapshots:
     dependencies:
       require-like: 0.1.2
 
-  evalite@1.0.0-beta.16(ai@6.0.116(zod@3.25.76))(better-sqlite3@11.10.0)(bufferutil@4.0.9):
+  evalite@1.0.0-beta.16(ai@6.0.116(zod@4.4.3))(better-sqlite3@11.10.0)(bufferutil@4.0.9):
     dependencies:
       '@fastify/static': 8.2.0
       '@fastify/websocket': 11.2.0(bufferutil@4.0.9)
@@ -25324,7 +25316,7 @@ snapshots:
       table: 6.9.0
       tinyrainbow: 3.1.0
     optionalDependencies:
-      ai: 6.0.116(zod@3.25.76)
+      ai: 6.0.116(zod@4.4.3)
       better-sqlite3: 11.10.0
     transitivePeerDependencies:
       - bufferutil
@@ -28219,7 +28211,7 @@ snapshots:
     transitivePeerDependencies:
       - encoding
 
-  openai@4.97.0(encoding@0.1.13)(ws@8.21.0(bufferutil@4.0.9))(zod@3.25.76):
+  openai@4.97.0(encoding@0.1.13)(ws@8.21.0(bufferutil@4.0.9))(zod@4.4.3):
     dependencies:
       '@types/node': 24.13.3
       '@types/node-fetch': 2.6.12
@@ -28230,7 +28222,7 @@ snapshots:
       node-fetch: 2.6.12(encoding@0.1.13)
     optionalDependencies:
       ws: 8.21.0(bufferutil@4.0.9)
-      zod: 3.25.76
+      zod: 4.4.3
     transitivePeerDependencies:
       - encoding
 
@@ -29561,7 +29553,7 @@ snapshots:
       '@remix-run/server-runtime': 2.17.5(typescript@6.0.3)
       react: 18.3.1
 
-  remix-utils@7.7.0(@remix-run/node@2.17.5(typescript@6.0.3))(@remix-run/react@2.17.5(react-dom@18.3.1(react@18.3.1))(react@18.3.1)(typescript@6.0.3))(@remix-run/router@1.23.3(patch_hash=33e2966e9ef36aa09955cec9922c5063227b83429157a71ba226369a08627ac9))(crypto-js@4.2.0)(intl-parse-accept-language@1.0.0)(react@18.3.1)(zod@3.25.76):
+  remix-utils@7.7.0(@remix-run/node@2.17.5(typescript@6.0.3))(@remix-run/react@2.17.5(react-dom@18.3.1(react@18.3.1))(react@18.3.1)(typescript@6.0.3))(@remix-run/router@1.23.3(patch_hash=33e2966e9ef36aa09955cec9922c5063227b83429157a71ba226369a08627ac9))(crypto-js@4.2.0)(intl-parse-accept-language@1.0.0)(react@18.3.1)(zod@4.4.3):
     dependencies:
       type-fest: 4.33.0
     optionalDependencies:
@@ -29571,7 +29563,7 @@ snapshots:
       crypto-js: 4.2.0
       intl-parse-accept-language: 1.0.0
       react: 18.3.1
-      zod: 3.25.76
+      zod: 4.4.3
 
   remove-accents@0.5.0: {}
 
@@ -31686,31 +31678,25 @@ snapshots:
       compress-commons: 6.0.2
       readable-stream: 4.7.0
 
-  zod-error@1.5.0:
+  zod-error@2.0.0(zod@4.4.3):
     dependencies:
-      zod: 3.25.76
-
-  zod-to-json-schema@3.24.5(zod@3.25.76):
-    dependencies:
-      zod: 3.25.76
+      zod: 4.4.3
 
-  zod-to-json-schema@3.24.6(zod@3.25.76):
+  zod-to-json-schema@3.24.5(zod@4.4.3):
     dependencies:
-      zod: 3.25.76
+      zod: 4.4.3
 
-  zod-to-json-schema@3.25.0(zod@3.25.76):
+  zod-to-json-schema@3.25.0(zod@4.4.3):
     dependencies:
-      zod: 3.25.76
+      zod: 4.4.3
 
-  zod-to-json-schema@3.25.1(zod@3.25.76):
+  zod-to-json-schema@3.25.1(zod@4.4.3):
     dependencies:
-      zod: 3.25.76
+      zod: 4.4.3
 
-  zod-validation-error@1.5.0(zod@3.25.76):
+  zod-validation-error@5.0.0(zod@4.4.3):
     dependencies:
-      zod: 3.25.76
-
-  zod@3.25.76: {}
+      zod: 4.4.3
 
   zod@4.4.3: {}