moonrepo/moon: A build system and monorepo management tool for the web ecosystem, written in Rust.

A build system and monorepo management tool for the web ecosystem, written in Rust. - moonrepo/moon

Summary

moon is a build system and monorepo management tool written in Rust for the web ecosystem. It handles repository organization, task orchestration, and notifications across many runtimes, and is designed for incremental adoption rather than all-at-once migration.

What it is useful for

moon targets teams running multi-package repositories that need to coordinate tasks, dependencies, and tool versions across JavaScript, TypeScript, Node.js, Bun, Deno, Python, Ruby, Rust, and Go. The README describes it as a replacement for sprawling package.json scripts: instead of duplicating commands across every package, you refer to tasks by project name. It also enforces consistent tool versions across the workspace, generates a project graph for dependency relationships, and supports remote caching so builds, hashes, and caches can be shared between teammates and CI/CD environments. Other documented capabilities include scaffolding new applications or libraries, generating a CODEOWNERS file, an action pipeline that runs tasks in parallel using a dependency graph, and webhook or terminal notifications when builds succeed or fail.

A caveat from the README: the feature list explicitly notes "Not all features are currently supported, view the documentation for an accurate list," so engineers should verify the current state of any given capability in the official docs before relying on it.

How engineers can use it

The README does not include install or setup commands, only linking to the documentation site. To start, an engineer would visit the docs at moonrepo.dev to install the binary, then migrate a monorepo project by project or task by task. Common workflows include running a named task for a single project, generating a project graph to visualize package dependencies, declaring tool versions in the workspace configuration, and integrating moon into CI/CD so the remote cache can be reused. A reasonable first step is replacing one root package.json script with a moon task and verifying the output matches the previous behavior. For setup, configuration, and contributing details, the README points readers to the documentation site and the project's CONTRIBUTING.md.