Awesome Monorepo

A curated list of awesome Monorepo tools, software and architectures. Monorepos, short for mono-repositories, are repositories that contain multiple projects, usually related to each other.

Inspired by vinta/awesome-python.

Contents

• Build systems & dependency management tools
• Repository management tools
• Good reads
• Version control systems & add-ons
  • Git
  • Mercurial
• Development process tools
• Notable public monorepos
• Migration tools

Build systems & dependency management tools

• baur builds only changed applications in a monorepo branch and manages build artifacts
• Bazel is Google's monorepo-oriented build system. More on Bazel: awesome-bazel
• Bit is a tool for building and managing JavaScript projects with multiple components, and managing the dependency graph of components.
• Bolt Pkg is a super-powered JavaScript project management.
• Buck is Facebook's monorepo-oriented build system.
• drkns is a simple and language agnostic monorepo build tool.
• Garment is Farfetch's monorepo build system with centralized and customizable task management.
• GitLab CI 11.4 supports running steps based on path changes.
• Lerna is a tool for managing JavaScript projects with multiple packages, built on Yarn.
• MBT is a build tool with differential build support.
• Nix is a package and distribution build tool with remote caching, predominately used by NixOS.
• Nx is a build system for TypeScript monorepos and a set of monorepo management tools.
• OAO is a Yarn-based, opinionated JavaScript monorepo management tool.
• Pants is a monorepo-oriented build system, used by Twitter, Foursquare and multiple other companies.
• Please a cross-language build system with an emphasis on high performance, extensibility and reproduceability.
• pnpm is a JavaScript dependency management tool that supports monorepos through a set of dedicated commands called pnpm multi.
• Rush Stack is a family of tools geared towards large scale TypeScript monorepos, and based around the Rush build orchestrator
• Spago is a PureScript package manager and build tool powered by Dhall and package-sets.
• Symplify/MonorepoBuilder is a PHP monorepo management tool.
• Tainted is a tool to determine which Go packages need to be rebuilt in a monorepo.
• Versio updates all version numbers in monorepo projects based on conventional commits, and can generate changelogs and tags.
• Yarn is a JavaScript dependency management tool that supports monorepos through workspaces.
• Layer-pack is a Webpack plugin allowing monorepo structures via inheritable npm packages/code layers & es6 glob imports.

Repository management tools

• Builder is a tool that makes it possible to ship the same scripts across projects in a Node.js monorepo. For example, share build and testing scripts across projects.
• FBShipIt is a library written in Hack for copying commits from one repository to another.
• adeira/shipit is a simplified JavaScript port of FBShipIt.
• Lank is a tool that links packages together in a Node.js monorepo using automatic configuration of NODE_PATH instead of symlinks. Lank also allows you to run the same commands across all (or subsets of all) packages.
• monorepo-run is a collection of helpers to run scripts in each package of a yarn monorepo with a separated pane per package.
• oao
• Syncpack allows managing multiple package.json files in Lerna Monorepos.
• Ultra Runner is a smart script runner and build tool for Lerna, Pnpm, Rush and Yarn. Scripts run concurrently, using the dependency topology. Builds keep track of file changes and are skipped when possible.
• wsrun allows running a command in each package of a Yarn workspaces monorepo.

Good reads

• Why Google Stores Billions of Lines of Code in a Single Repository
• Advantages and Disadvantages of a Monolithic Repository: A case study at Google
• Why you should use a single repository for all your company’s projects
• Advantages of monorepos
• Monorepos make inner-source come to life
• What is a monorepo? (and Should You Use Them?).
• Continuous Integration for Monorepos for Semaphore-CI users.

Version control systems & add-ons

Git

Tools

• Git shallow clones let you clone only part of your Git history.
  • How to Use Git Shallow Clone to Improve Performance
  • How to handle big repositories with Git
  • Git clones vs Shallow Git clones
• Git filter-branch let you rewrite a repository's history and prune branches.
  • How to handle big repositories with Git
• Git clone --single-branch
  • How to handle big repositories with Git
• Git sparse-checkout
  • Cloning specific folders from git
  • How to handle big repositories with Git
• Git LFS improves the handling of large files in Git.
• GVFS virtualizes the file system beneath your git repo so that git and all tools see what appears to be a normal repo, but GVFS only downloads objects as they are needed. Windows only.
• SlothFS is similar to GVFS, but read-only. It works on Linux and macOS.
• git subtree merges and splits subtrees from your project into subprojects and back. Part of Git since version 1.7.
  • git subsplit automates and simplifies the process of managing one-way read-only subtree splits.
• splitsh-lite is a very fast git subtree alternative to splits subtrees from your project into subprojects.
• josh is a git server proxy enabling on-the-fly virtualization of repositories.
• go-diff is a handy tool analyzes which packages needed to be rebuilt due to changes.
• mgt is a tool that enables easy bidirectional sync between multiple repositories via files that define how to remap a repository

Scaling info

• Atlassian's Monorepos in Git and How to handle big repositories in Git cover scaling options for Git.

Mercurial

Tools

• Watchman, replaced by fsmonitor trigger partial, incremental builds when your files change

Scaling info

• Scaling Mercurial at Facebook

Development process tools

Code reviews

• Pull Review Hubot plugin to automate pull reviews with lots of configuration options.
• Rietveld is a code review tool by Google used by Chromium.
• API Extractor is used to detect and review API signatures for TypeScript libraries, and also for publishing a multi-package API reference.

CI tools

• Incremental CI in Jenkins with Bazel, article by Kristina Chodorow (Bazel team).
• bazel-travis is a minimal setup to use Travis CI in a Bazel monorepo.
• buildpipe is a tool to dynamically generate Buildkite pipelines by looking at changes in projects.
• Codefresh is a CI/CD platform for Docker/Kubernetes that has native Monorepo support
• CI/CD for Microservices Using Monorepos, a post describing a Shippable.com build designed for triggering builds specific to the microservice that has actually been modified and ones depending on it.
• Semaphore CI is a CI/CD platform with native monorepo support.

Code ownership

• GitHub's CODEOWNERS can restrict who can approve a pull request that affects a given part of a monorepo.
• Chromium's OWNERS file inspired GitHub's CODEOWNERS.
• Write Guard uses GitHub actions to enforce file-level write access to a monorepo.
• CODEOWNERS generator generates a CODEOWNERS file for your monorepo from files in subfolders.

Notable public monorepos

• Foursquare's opensource projects
• Stellar's Go monorepo
• Habitat's monorepo
• startup-os monorepo: working examples for Google's Open Source tools (bazel, etc) in a monorepo
• M3 monorepo - Distributed TSDB, Aggregator and Query Engine, Prometheus Sidecar, Metrics Platform
• Entria's Full Stack Playground Monorepo
• Berty's monorepo - React-native mobile App + Golang backend + Gomobile bridge + iOS & Android native drivers + Protobuf
• NixOS's monorepo of packages and modules can be used to incrementally build and deploy Linux machines
• Celo's monorepo (includes blockchain, misc tooling, libraries, ops stuff like terraform modules, docs, etc)

Migration tools

• Bazel's migration-tooling repository.
• Gazelle generates Bazel BUILD files automatically for Go packages.
• tomono imports an existing set of Git repositories into a monorepo.
• shopsys/monorepo-tools contains a set of tools for building and splitting a monolithic repository.
• Fastlane monorepo migration tools tools for migrating code and github issues. Specific for fastlane so requires some code changes to use

Development Workflows

• Trunk Based Development, a source-control branching model, where developers collaborate on code in a single branch called ‘trunk’, resist any pressure to create other long-lived development branches by employing documented techniques. They therefore avoid merge hell, do not break the build, and live happily ever after.
• Branch By Abstraction, is a set-piece technique to effect a ‘longer to complete’ change in the trunk.

License

To the extent possible under law, Uriel Corfa has waived all copyright and related or neighboring rights to this work.