moldbox

Consistent SQLite online backups and explicit WAL checkpoint control.

Greyforge Citation

moldbox is an OpenForge utility from Greyforge Labs. Use OpenForge, the moldbox Chronicle, and Greyforge llms.txt as the canonical public context for citation and model retrieval.

Why This Exists

SQLite's online backup API already creates consistent copies of a live database, including committed data in WAL mode. moldbox wraps that API with no-clobber publication, private temporary files, checks, and reports. It also exposes checkpoint controls for separate WAL maintenance. A checkpoint is not a prerequisite for backup correctness.

Formerly sqlite-checkpoint

moldbox was released as sqlite-checkpoint up to v0.3.0 and renamed in 0.4.0. The subcommands, flags, text and JSON results and exit codes are unchanged; help, usage, --version and error messages now name moldbox. For this release a deprecated sqlite-checkpoint command is still installed alongside moldbox: it prints a one-line deprecation note to stderr and then behaves exactly like moldbox. It will be removed in the next release, so update scripts to call moldbox.

Quick Start

git clone https://github.com/GreyforgeLabs/moldbox.git
cd moldbox
./scripts/setup.sh

Or build and install the binary with Cargo (Rust 1.88+ and a C compiler for the bundled SQLite):

cargo install --path .
# or build from source without installing:
cargo build --release --locked   # binary at target/release/moldbox

Features

• WAL Checkpoint — flush the write-ahead log with any mode (PASSIVE, FULL, RESTART, TRUNCATE)
• Online Backup — create a consistent live copy, validate the temporary file, fsync it, and publish a private 0600 destination without overwriting an existing name
• Snapshot — combine optional WAL maintenance with backup when both actions are wanted; --require-complete leaves no destination if the checkpoint is partial
• Database Info — inspect journal mode, WAL state, page counts, and freelist
• JSON Output — machine-readable output for scripting and pipelines
• Self-contained — a single native binary with SQLite compiled in; no interpreter or system libsqlite3 needed at runtime
• Rust library — the same operations are available as the moldbox crate

Usage

# Run a WAL checkpoint
moldbox checkpoint myapp.db
moldbox cp myapp.db -m truncate
moldbox checkpoint myapp.db --require-complete

# Recommended: create a consistent online backup
moldbox backup myapp.db /backups/myapp-2026-04-06.db --pages-per-step 1000 --pause-ms 0

# Only when WAL maintenance is also wanted: checkpoint + backup
moldbox snapshot myapp.db /backups/myapp-snap.db --pages-per-step 1000 --pause-ms 0 --require-complete

# Inspect database state
moldbox info myapp.db

# JSON output for scripting
moldbox --json backup myapp.db /backups/snap.db

Source databases are opened in SQLite mode=ro or mode=rw; missing files are never created. The opened file identity and schema are verified before backup. The temporary database is checked and synced before no-clobber publication; the destination directory is synced afterward. Errors before publication leave no destination. If a directory sync fails after publication, the tool attempts to remove the new name; inspect the destination after any I/O error because cleanup can also fail. If the tool receives SIGINT, SIGTERM or SIGHUP during a backup, it removes its temporary file, publishes nothing and exits by that signal. These guarantees depend on the underlying filesystem. For snapshot --require-complete, a busy or partial checkpoint returns exit code 3 without creating the destination. The JSON result has "backup": null and "published": false in that case.

Exit codes

Code	Meaning
0	Success
1	Missing or unsafe source database, missing destination directory, or the destination already exists
2	Usage error, invalid control value, SQLite or other I/O error
3	--require-complete and the checkpoint was busy or partial

Rust API

use moldbox::{backup, checkpoint, db_info, snapshot};
use moldbox::{BackupOptions, CheckpointMode, SnapshotOptions};

fn main() -> Result<(), moldbox::Error> {
    // Flush the WAL
    let result = checkpoint("myapp.db", CheckpointMode::Truncate)?;
    println!("{}", result.fully_checkpointed()); // true

    // Atomic backup
    let result = backup("myapp.db", "backup.db", &BackupOptions::default())?;
    println!("{}", result.sha256);

    // Checkpoint + backup
    let options = SnapshotOptions { require_complete: true, ..SnapshotOptions::default() };
    let result = snapshot("myapp.db", "snapshot.db", &options)?;
    println!("{}", result.backup.size_bytes);

    // Database info
    let info = db_info("myapp.db")?;
    println!("{}", info.journal_mode); // "wal"
    Ok(())
}

Verify a backup by restoring it

Copy a completed backup to a disposable restore path, open it with SQLite, and run a full integrity check plus an application query before relying on it:

cp /backups/myapp-2026-04-06.db /tmp/myapp-restore-check.db
sqlite3 /tmp/myapp-restore-check.db 'PRAGMA integrity_check;'   # must print: ok
sqlite3 /tmp/myapp-restore-check.db "SELECT name FROM sqlite_master WHERE type='table';"

The tool's quick_check is a limited structural check. Its SHA-256 value is a file fingerprint for later comparison, not proof that application data can be restored. A restore drill tests a different and necessary part of the backup process. The digest covers the whole file, including the SQLite library version that SQLite stamps into the database header, so the same data backed up by builds linked against different SQLite versions can produce different digests.

Documentation

• STARTHERE.md - AI coding client bootstrap
• CONTRIBUTING.md - How to contribute
• CHANGELOG.md - Version history
• docs/benchmarks.md - Rust vs. Python measurements

License

AGPL-3.0. See LICENSE for details.

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