Buck2 vs build2
Buck2
buck2.buildbuild2
build2.orgSide by side
| Figure | Buck2 | build2 |
|---|---|---|
| Price from | Free | — |
| Free plan | Yes | — |
| Free trial | — | — |
| Open source | — | — |
| Windows | Yes | Yes |
| macOS | Yes | Yes |
| Linux | Yes | Yes |
| Self-hosted | Yes | — |
| Plans published | 1 | 0 |
| Spec score · Build Automation Software | 8.1 (#12) | 7.7 (#19) |
| Integrations | The project says BuildBarn, BuildBuddy, EngFlow, and NativeLink work with its distributed compilation support through the Bazel Remote Execution API. | build2 supports system package manager interactions for Debian, Fedora, and similar distributions, including querying installed package versions and optionally installing dependencies from system repositories. |
Plans
In their own words
Buck2
Buck2 is a free build system from Meta for large-scale repositories that combine multiple programming languages. It uses Starlark rules, a dynamic dependency graph, and incremental actions to support extensible builds. Its language table lists prelude rules for C/C++, Erlang, Go, Haskell, Java, Kotlin, OCaml, Python, and Rust, though usability varies by language. Build actions can run remotely through services exposing Bazel's remote execution API; the project lists BuildBarn, BuildBuddy, EngFlow, and NativeLink as compatible with its distributed compilation support. Buck2 supports filesystem watching and can integrate with Meta's optional Eden virtual filesystem. Rules are hermetic by default and missing dependencies are errors, but local-only build steps are not sandboxed. The project describes Buck2 as early-stage and says it has no stable release tag; its latest binary tag changes with repository pushes. It warns that outside users may encounter rough edges, missing features, and missing toolchains. Source and binaries are available under MIT and Apache-2.0 licenses. The project directs users to GitHub for issue reports and offers a community Discord server.