FASTBuild vs Ninja
FASTBuild
fastbuild.orgNinja
ninja-build.orgSide by side
| Figure | FASTBuild | Ninja |
|---|---|---|
| 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) | 8.1 (#13) |
| Integrations | The download page lists third-party Unreal Engine 4 integrations and Visual Studio and VSCode-related tooling. | GN and CMake can generate Ninja files; the manual also names Premake as a possible fit. |
| License | The license permits use for any purpose, including commercial applications, and permits alteration and redistribution subject to stated conditions. | The project repository identifies its license as Apache-2.0. |
| Parallel builds | FASTBuild runs compilation tasks across worker threads to use CPU cores efficiently. | Builds run in parallel by default, based on the number of CPUs on the system. |
| Platforms | The current download page lists Windows x64, OS X x64 and ARM, and Linux x64 builds for v1.20. | The manual says Ninja works on Unix-like systems and Windows, and runs on Mac OS X and FreeBSD. |
| Purpose | FASTBuild is an open-source build system for scalable compilation, caching, and network distribution. | Ninja is a small build system designed to evaluate incremental builds quickly. |
| Support | The site directs bug reports, feature requests and questions to GitHub issues and provides online or downloadable documentation. | The project site links to a mailing list and lists the #ninja-build IRC channel on irc.oftc.net. |
| 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. | The site says Ninja is used to build Google Chrome, parts of Android, and LLVM. |
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.