cargo-rail

Rust monorepo tooling for change detection, graph unification, release automation, and split/sync.

What It Covers

plan / run: file-first change detection for selective build, test, bench, docs, and infra execution
unify: workspace dependency unification, feature cleanup, unused dependency detection, and MSRV derivation
release: version bump, changelog generation, tagging, and publish flow without a large external toolchain
split / sync: copybara-style crate extraction and bidirectional sync without a separate DSL

Quick Start

bash
cargo install cargo-rail

cargo rail init
cargo rail unify --check
cargo rail plan --merge-base --explain
cargo rail run --merge-base --profile ci

Pre-built binaries: GitHub Releases

Core Workflows

Change Detection

Use plan to build the deterministic contract and run to execute only the selected work.

bash
cargo rail plan --merge-base
cargo rail plan --merge-base -f github
cargo rail run --merge-base --profile ci

impact is diagnostic. scope is the execution handoff.

Graph Unification

Use unify to keep the workspace dependency graph lean and consistent.

bash
cargo rail unify --check
cargo rail unify --check --explain
cargo rail unify

Release Workflow

Use release for checks, changelog generation, tags, remote push, GitHub Releases, and publish ordering.

bash
cargo rail release check
cargo rail release run cargo-rail --bump patch --yes

For an owned GitHub release, set both push = true and create_github_release = true.
cargo-rail pushes the release commit and tag before publishing crates or making the GitHub Release public.

Split / Sync

Use split and sync when a crate needs to live in both a monorepo and a standalone repository.

bash
cargo rail split init crates/my-crate
cargo rail split run crates/my-crate
cargo rail sync crates/my-crate --to-remote

GitHub Actions

Use cargo-rail-action for planner gates and execution scope in GitHub Actions.

Config

bash
cargo rail init
cargo rail config sync
cargo rail config validate

Primary references:

Migration

Migrate from cargo-hakari

Getting Help

Issues: GitHub Issues
Crate: crates.io/cargo-rail

Contributing

See CONTRIBUTING.md.

Security

See SECURITY.md.

License

Licensed under MIT.

Cargo rail