diff --git a/tests/release/packages/solid-reactivity/.gitignore b/tests/release/packages/solid-reactivity/.gitignore
new file mode 100644
index 0000000000..8861e2a33d
--- /dev/null
+++ b/tests/release/packages/solid-reactivity/.gitignore
@@ -0,0 +1,3 @@
+/out
+/*.log
+/*-out.txt
diff --git a/tests/release/packages/solid-reactivity/README.md b/tests/release/packages/solid-reactivity/README.md
new file mode 100644
index 0000000000..6ee2f59cfa
--- /dev/null
+++ b/tests/release/packages/solid-reactivity/README.md
@@ -0,0 +1,91 @@
+# Solid client-runtime audit
+
+This is the first prerequisite for the native UI bridge in [#4644](https://github.com/PerryTS/perry/issues/4644).
+It compiles the installed, unmodified Solid 1.9.15 core, store, and universal
+renderer to native code and compares their output with Node. No display server
+or JavaScript runtime is needed by the resulting binary.
+
+```sh
+PERRY_BIN=/absolute/path/to/perry \
+  tests/release/packages/_harness.sh --filter solid-reactivity
+```
+
+Use the repository's `.node-version` for the oracle. The release sweep's
+package tier discovers this fixture automatically. Its lockfile pins Solid
+and its transitive dependencies; `fixture.sh` uses `npm ci` on a fresh checkout.
+
+The fixture exercises:
+
+- Signals, memo invalidation, batched updates, equality suppression, and disposal.
+- Dynamic effect dependencies and cleanup before reruns and disposal.
+- Store proxies, nested reads, updater functions, `produce`, keyed `reconcile`,
+  preserved item identity, and `unwrap`.
+- The real universal renderer over an in-memory host: keyed insertion,
+  anchored reordering, replacement, removal, owner cleanup, and text updates
+  that preserve node identity.
+
+## Selecting the reactive build
+
+Solid's `node` export selects its server implementation. That implementation
+does not subscribe effects to updates. Perry's normal Node-compatible package
+resolution therefore needs these existing project aliases for a reactive app:
+
+```json
+{
+  "perry": {
+    "compilePackages": ["solid-js"],
+    "allow": { "compilePackages": ["solid-js"] },
+    "packageAliases": {
+      "solid-js": "solid-js/dist/solid.js",
+      "solid-js/store": "solid-js/store/dist/store.js"
+    }
+  }
+}
+```
+
+The core alias also applies to imports inside the store and universal renderer,
+so they share the same owner and dependency state. Importing the client core
+only in the app would leave those internal imports pointing at the server
+build. The Node oracle uses `--conditions=browser` to select the corresponding
+client exports.
+
+This fixture does not establish a `perry/ui` adapter, native event handling,
+or a Solid JSX compiler mode. It also does not audit resources, transitions,
+hydration, or every store operation. Solid's bundled `h` and `html` entry
+points use its web renderer; they are not a native hyperscript API. See
+[Solid's universal-renderer contract](https://github.com/solidjs/solid/blob/main/packages/solid/universal/README.md)
+for the host operations and the separate universal JSX transform.
+
+## Moving-GC verification finding
+
+On main `d36a1af0c`, the normal fixture matches the Node oracle. A forced
+copying run with seed 4644 and protected from-space also matches (22 copying
+minors, 14,022 moved objects on macOS arm64). Enabling the evacuation verifier
+exposes a failure during store creation:
+
+```sh
+PERRY_GC_SCHEDULE_SEED=4644 PERRY_GC_SCHEDULE_RATE=1 \
+PERRY_GC_PROTECT_FROMSPACE=1 PERRY_GC_VERIFY_EVACUATION=1 \
+  tests/release/packages/solid-reactivity/out
+```
+
+The verifier reports `stale forwarded pointer in remembered dirty ranges` at
+the fifth scheduled collection. A store-only reduction also reproduces a
+stale pointer in `heap fields`. The signal-only probe passes verification.
+This finding needs resolution before declaring the native bridge's GC audit
+complete; normal output parity alone does not resolve it.
+
+Further isolation identified the reported field as the effect computation's
+`sources` array after growing from capacity 8 to 16. Both the old forwarding
+stub and its target are tenured. Array growth deliberately retains such
+aliases for `clean_arr_ptr` to follow, whereas the verifier currently rejects
+any forwarded reference. The follow-up needs to distinguish those retained
+growth aliases from evacuation originals that are about to be reclaimed.
+
+The correction is proposed in [#9822](https://github.com/PerryTS/perry/pull/9822).
+With that change, this fixture matches all 20 oracle lines with both protected
+from-space and evacuation verification enabled: seed 4644/rate 1 completes
+22 copying minors and moves 14,022 objects. Seeds 1/rate 0.25 and 42/rate 0.1
+also pass, completing six and one copying minors respectively. The runtime
+regressions also check that direct and indirect nursery forwarding references
+are still rejected.
diff --git a/tests/release/packages/solid-reactivity/entry.ts b/tests/release/packages/solid-reactivity/entry.ts
new file mode 100644
index 0000000000..caa14d4984
--- /dev/null
+++ b/tests/release/packages/solid-reactivity/entry.ts
@@ -0,0 +1,145 @@
+// #4644: exercise the installed client runtime, including the shared owner
+// and listener state used by solid-js/store and solid-js/universal.
+import {
+  batch, createComponent, createMemo, createRenderEffect, createRoot,
+  createSignal, For, onCleanup, untrack,
+} from "solid-js";
+import { createStore, produce, reconcile, unwrap } from "solid-js/store";
+import { createRenderer } from "solid-js/universal";
+
+const state = createRoot(dispose => {
+  const [count, setCount] = createSignal(1);
+  const doubled = createMemo(() => count() * 2);
+  const values: number[] = [];
+  createRenderEffect(() => { values.push(doubled()); });
+  onCleanup(() => console.log("signal cleanup"));
+  return { count, setCount, doubled, values, dispose };
+});
+console.log("initial", state.count(), state.doubled(), state.values.join(","));
+state.setCount(2);
+console.log("update", state.count(), state.doubled(), state.values.join(","));
+batch(() => { state.setCount(3); state.setCount(4); });
+state.setCount(4); // Equal writes must not notify.
+console.log("batch", state.count(), state.doubled(), state.values.join(","));
+console.log("untrack", untrack(state.count));
+state.dispose();
+state.setCount(5);
+console.log("disposed", state.values.join(","));
+
+const branch = createRoot(dispose => {
+  const [left, setLeft] = createSignal(true);
+  const [a, setA] = createSignal(1);
+  const [b, setB] = createSignal(10);
+  const seen: number[] = [];
+  let cleanups = 0;
+  createRenderEffect(() => {
+    seen.push(left() ? a() : b());
+    onCleanup(() => { cleanups++; });
+  });
+  return { setLeft, setA, setB, seen, cleanups: () => cleanups, dispose };
+});
+branch.setB(11); // The inactive dependency is not subscribed.
+branch.setA(2);
+branch.setLeft(false);
+branch.setA(3); // The old dependency must have been removed.
+branch.setB(12);
+console.log("branches", branch.seen.join(","), branch.cleanups());
+branch.dispose();
+console.log("branch cleanup", branch.cleanups());
+
+const store = createRoot(dispose => {
+  const [value, setValue] = createStore({
+    user: { name: "Ada", score: 1 },
+    items: [{ id: 1, value: "one" }, { id: 2, value: "two" }],
+  });
+  const seen: string[] = [];
+  createRenderEffect(() => {
+    seen.push(value.user.name + ":" + value.user.score + ":" +
+      value.items.map(item => item.value).join(","));
+  });
+  return { value, setValue, seen, dispose };
+});
+console.log("store", store.seen.join("|"));
+store.setValue("user", "score", score => score + 1);
+store.setValue("user", produce(user => { user.name = "Grace"; }));
+console.log("store updates", store.seen.join("|"));
+const first = store.value.items[0];
+store.setValue("items", reconcile([{ id: 2, value: "TWO" }, { id: 1, value: "ONE" }]));
+console.log("reconcile", store.seen.join("|"));
+console.log("store identity", first === store.value.items[1]);
+console.log("unwrap", unwrap(store.value).user.name);
+store.dispose();
+store.setValue("user", "score", 9);
+console.log("store disposed", store.seen.length);
+
+// An in-memory host keeps this audit independent of a display server. The
+// actual Solid renderer drives these operations, including anchored moves.
+interface HostNode {
+  kind: string;
+  value: string;
+  children: HostNode[];
+  parent: HostNode | undefined;
+}
+function hostNode(kind: string, value = ""): HostNode {
+  return { kind, value, children: [], parent: undefined };
+}
+function remove(parent: HostNode, node: HostNode): void {
+  const index = parent.children.indexOf(node);
+  if (index < 0) throw new Error("removing a non-child");
+  parent.children.splice(index, 1);
+  node.parent = undefined;
+}
+const renderer = createRenderer<HostNode>({
+  createElement: kind => hostNode(kind),
+  createTextNode: value => hostNode("text", value),
+  replaceText: (node, value) => { node.value = value; },
+  setProperty: (node, name, value) => {
+    if (name !== "value") throw new Error("unexpected property " + name);
+    node.value = String(value);
+  },
+  insertNode(parent, node, anchor) {
+    if (node === anchor) return;
+    if (node.parent) remove(node.parent, node);
+    const index = anchor ? parent.children.indexOf(anchor) : parent.children.length;
+    if (index < 0) throw new Error("anchor is not a child");
+    parent.children.splice(index, 0, node);
+    node.parent = parent;
+  },
+  isTextNode: node => node.kind === "text",
+  removeNode: remove,
+  getParentNode: node => node.parent,
+  getFirstChild: node => node.children[0],
+  getNextSibling: node => node.parent?.children[node.parent.children.indexOf(node) + 1],
+});
+
+const root = hostNode("root");
+const [rows, setRows] = createSignal(["a", "b", "c"]);
+let creations = 0;
+let rowCleanups = 0;
+const disposeRows = renderer.render(() => createComponent(For, {
+  get each() { return rows(); },
+  children: item => {
+    creations++;
+    onCleanup(() => { rowCleanups++; });
+    return renderer.createTextNode(item);
+  },
+}), root);
+const originalA = root.children[0];
+console.log("rows", root.children.map(node => node.value).join(","));
+setRows(["c", "a", "b"]);
+console.log("moved", root.children.map(node => node.value).join(","), root.children[1] === originalA, creations);
+setRows(["b", "d"]);
+console.log("replaced", root.children.map(node => node.value).join(","), creations, rowCleanups);
+setRows([]);
+console.log("empty", root.children.map(node => node.value).join(","), rowCleanups);
+disposeRows();
+setRows(["after disposal"]);
+console.log("rows disposed", creations, rowCleanups);
+
+const labelRoot = hostNode("root");
+const [label, setLabel] = createSignal("before");
+const disposeLabel = renderer.render(() => label, labelRoot);
+const originalLabel = labelRoot.children[0];
+setLabel("after");
+console.log("text update", labelRoot.children[0].value, labelRoot.children[0] === originalLabel);
+disposeLabel();
diff --git a/tests/release/packages/solid-reactivity/expected.txt b/tests/release/packages/solid-reactivity/expected.txt
new file mode 100644
index 0000000000..cfccf83928
--- /dev/null
+++ b/tests/release/packages/solid-reactivity/expected.txt
@@ -0,0 +1,20 @@
+initial 1 2 2
+update 2 4 2,4
+batch 4 8 2,4,8
+untrack 4
+signal cleanup
+disposed 2,4,8
+branches 1,2,11,12 3
+branch cleanup 4
+store Ada:1:one,two
+store updates Ada:1:one,two|Ada:2:one,two|Grace:2:one,two
+reconcile Ada:1:one,two|Ada:2:one,two|Grace:2:one,two|Grace:2:TWO,ONE
+store identity true
+unwrap Grace
+store disposed 4
+rows a,b,c
+moved c,a,b true 3
+replaced b,d 4 2
+empty  4
+rows disposed 4 4
+text update after true
diff --git a/tests/release/packages/solid-reactivity/fixture.sh b/tests/release/packages/solid-reactivity/fixture.sh
new file mode 100755
index 0000000000..2f97ec7aab
--- /dev/null
+++ b/tests/release/packages/solid-reactivity/fixture.sh
@@ -0,0 +1,21 @@
+#!/usr/bin/env bash
+set -euo pipefail
+[[ "${1:-}" == "--__did-skip-marker" ]] && exit 1
+cd "$(dirname "$0")"
+source ../_fixture_lib.sh
+if [[ ! -d node_modules ]]; then
+  npm ci --ignore-scripts --no-audit --no-fund
+fi
+fixture_setup "solid-reactivity"
+
+# Solid's default Node export is intentionally non-reactive SSR. Use the
+# client condition for the oracle, matching packageAliases in package.json.
+node --conditions=browser entry.ts > node-out.txt
+diff -u expected.txt node-out.txt
+# A whole-build cache hit emits no module census. Keep object-cache reuse,
+# but perform module collection so the native-only assertion is meaningful.
+PERRY_DISABLE_BUILD_CACHE=1 fixture_compile_run_diff "solid-reactivity"
+if ! grep -Eq 'Found [0-9]+ module\(s\): [1-9][0-9]* native, 0 JavaScript' perry-compile.log; then
+  echo "FAIL solid-reactivity — expected every module to compile natively"
+  exit 1
+fi
diff --git a/tests/release/packages/solid-reactivity/package-lock.json b/tests/release/packages/solid-reactivity/package-lock.json
new file mode 100644
index 0000000000..ba2d9fd35b
--- /dev/null
+++ b/tests/release/packages/solid-reactivity/package-lock.json
@@ -0,0 +1,53 @@
+{
+  "name": "perry-release-fixture-solid-reactivity",
+  "version": "0.0.0",
+  "lockfileVersion": 3,
+  "requires": true,
+  "packages": {
+    "": {
+      "name": "perry-release-fixture-solid-reactivity",
+      "version": "0.0.0",
+      "dependencies": {
+        "solid-js": "1.9.15"
+      }
+    },
+    "node_modules/csstype": {
+      "version": "3.2.3",
+      "resolved": "https://registry.npmjs.org/csstype/-/csstype-3.2.3.tgz",
+      "integrity": "sha512-z1HGKcYy2xA8AGQfwrn0PAy+PB7X/GSj3UVJW9qKyn43xWa+gl5nXmU4qqLMRzWVLFC8KusUX8T/0kCiOYpAIQ==",
+      "license": "MIT"
+    },
+    "node_modules/seroval": {
+      "version": "1.5.6",
+      "resolved": "https://registry.npmjs.org/seroval/-/seroval-1.5.6.tgz",
+      "integrity": "sha512-rVQVWjjSvlINzaQPZH5JFqsqEsIWdTxY3iJZCnTL/5gQbXIRooVZKI60tVCkOVfzcRPejboxO2t0P89dg5mQaA==",
+      "license": "MIT",
+      "engines": {
+        "node": ">=10"
+      }
+    },
+    "node_modules/seroval-plugins": {
+      "version": "1.5.6",
+      "resolved": "https://registry.npmjs.org/seroval-plugins/-/seroval-plugins-1.5.6.tgz",
+      "integrity": "sha512-HXuLAX2pu/UByPpaeo/TaMfvMIi+1QqIoPJYCcAtU8QkVNwgR6MPlGuCQTErV1JwraaMbYaWVIBX7mppzGLATQ==",
+      "license": "MIT",
+      "engines": {
+        "node": ">=10"
+      },
+      "peerDependencies": {
+        "seroval": "^1.0"
+      }
+    },
+    "node_modules/solid-js": {
+      "version": "1.9.15",
+      "resolved": "https://registry.npmjs.org/solid-js/-/solid-js-1.9.15.tgz",
+      "integrity": "sha512-EeiY2xfpZJqPLjXspVEKjAII4yv8NyG//NxZ3IpOFHdUNnnTyL0uJOeS9LWGvA7cFCz5y94cjFwYlmw5Luncsg==",
+      "license": "MIT",
+      "dependencies": {
+        "csstype": "^3.1.0",
+        "seroval": "~1.5.4",
+        "seroval-plugins": "~1.5.4"
+      }
+    }
+  }
+}
diff --git a/tests/release/packages/solid-reactivity/package.json b/tests/release/packages/solid-reactivity/package.json
new file mode 100644
index 0000000000..71469be13b
--- /dev/null
+++ b/tests/release/packages/solid-reactivity/package.json
@@ -0,0 +1,18 @@
+{
+  "name": "perry-release-fixture-solid-reactivity",
+  "version": "0.0.0",
+  "private": true,
+  "type": "module",
+  "description": "Native Solid core, store, and universal-renderer audit for #4644",
+  "dependencies": {
+    "solid-js": "1.9.15"
+  },
+  "perry": {
+    "compilePackages": ["solid-js"],
+    "allow": { "compilePackages": ["solid-js"] },
+    "packageAliases": {
+      "solid-js": "solid-js/dist/solid.js",
+      "solid-js/store": "solid-js/store/dist/store.js"
+    }
+  }
+}