Buck2

Health v2 · maintenance only

Flags: prerelease_only

Adoption not part of the score

4481 stars · 413 forks observed · 2026-10-21

What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-29, confidence not recorded

Buck2 is Meta's fast, extensible, large-scale build system written in Rust, succeeding the original Buck (whose repository is now dead). It supports many languages (C++, Python, Rust, Java, Kotlin, Go, Haskell, OCaml, Erlang) with hermetic, Starlark-defined rules and remote build execution.

Use cases

• build a large multi-language monorepo
• replace make or bazel with a faster build system
• write custom build rules in starlark
• set up remote build execution and caching
• build c++ rust and java projects with one tool
• run ci that only builds what changed

When to choose

• you maintain a large monorepo spanning multiple languages
• you need hermetic, reproducible builds with remote execution
• you want extensible build rules written in Starlark
• build speed on large codebases is a priority

When to avoid

• you have a small single-language project where simpler tools suffice
• you need a mature ecosystem of third-party rules like Bazel's
• you rely on the original Buck - that repository is dead and unmaintained
• your team cannot invest in learning a new build system

Facets

cli-tool · maturity active

build-tool cli developer-tools developer-tools cross-platform windows cli rust starlark monorepo remote-execution hermetic-builds multi-language bazel-alternative incremental-build command-line linux macos

Member repositories

For agents

markdown · JSON · MCP: product_card(name="facebook/buck2")