Little nin' is ninja's little sibling.

Nin is an experimental fork of ninja translated in Go.

Install go1.17 or later.

go install github.com/maruel/nin/cmd/nin@latest

Use nin where you would have used ninja (or create a symlink).

Yeah.

The reason it's possible at all is because ninja is well written and has a reasonable amount of unit tests.

• The parser can be used as a library
  • This opens the door to a lot of opportunity and a real ecosystem
• Refactoring Go >> refactoring C++
  • As I made progress, I saw opportunities for simplification
• Making the code concurrent (e.g. making the parser parallel) is easier
• Plans to have it be stateful and/or do RPCs and change fundamental parts
  • E.g. call directly the RBE backend instead of shelling out reclient?
• It's easier to keep the performance promise in check, and keep it maintainable
  • Go has native benchmarking
  • Go has native CPU and memory profiling
  • Go has native code coverage
  • Go has native documentation
• Since it's GC, and the program runs as a one shot, we can just disable GC and save a significant amount of memory management (read: CPU) overhead.

I'll write a better roadmap if the project doesn't crash and burn.

Some people did advent of code 2021, I did a brain teaser instead.

• Go's slice and string bound checking slow things down, I'll have to micro optimize a bit.
• Go's function calls are more expensive and the Go compiler inlines less often than the C++ compiler. I'll reduce the number of function calls.
• Go's Windows layer is likely slower than raw C++, so I'll probably call raw syscall functions on Windows.
• Staying up to date changes done upstream, especially to the file format and correctness checks.

• Manifest (build.ninja) parsing: 5% faster on average! 📉
• Latency: nin is in the same ballpark (-5%) for building ninja itself.
• CPU usage: about 15% higher, has to be optimized.
• 16 test cases out of 394 (5%) have to be fixed. git grep Skip..TODO | wc -l versus git grep "^func Test" | wc -l.
• Closely tracking upstream as-is.
• Flag parsing is not 100% compatible yet.

See PERF.md to learn how to measure performance yourself, since I know myself enough that I will forget to update the stats above and it will get better over time.

Ninja is a small build system with a focus on speed. https://ninja-build.org/

See the manual or doc/manual.asciidoc included in the distribution for background and more details.