FASTBuild vs GN
FASTBuild
fastbuild.org
GN
gn.googlesource.comSide by side
| Figure | FASTBuild | GN |
|---|---|---|
| Price from | Free | Free |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | — | — |
| Windows | Yes | Yes |
| macOS | Yes | Yes |
| Linux | Yes | Yes |
| Plans published | 1 | 1 |
| Spec score · Build Automation Software | 8.6 (#6) | 7.9 (#15) |
| Purpose | FASTBuild is an open-source build system for scalable compilation, caching, and network distribution. | GN is a meta-build system that generates build files for Ninja. |
| Support | The site directs bug reports, feature requests and questions to GitHub issues and provides online or downloadable documentation. | Users can report bugs in the GN bug database and ask questions or follow development on the Chromium GN developers Google Group. |
| Use cases | The site says FASTBuild is used by large studios and independent developers to develop for PC, Mac, Linux, consoles, smartphones and retro systems. | GN is used as the build system for Chromium, Fuchsia, and related projects. |
Plans
In their own words
FASTBuild
FASTBuild is an open-source build system for compiling software across Linux, macOS and Windows. It runs compilation work across worker threads, can reuse results from local or network caches, and can distribute builds among networked machines when their settings and worker setup are compatible. The maker says caching can accelerate compile times up to 10x. Some compiler settings do not support caching or distribution; FASTBuild handles affected objects without caching or builds them locally. Supported toolchains include MSVC, GCC, SNC, Clang, GreenHills, CodeWarrior and NVCC, plus syntactically compatible command-line compilers. It can combine C++ files into Unity or Blob builds, while allowing writable files to be built individually for quicker iteration. FASTBuild can generate Visual Studio and XCode project files. The maker describes it as a self-contained executable that needs no installation or dependencies beyond compiler tools. It is free, with commercial use and redistribution allowed under license conditions; the license provides the software without warranty. The listed current release is v1.20, released 26-Apr-2026.