[ANN] The dk0 build system

Ecosystem
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It is my pleasure to announce the first official release of dk0. It is a build system with the following features:

  • Written in OCaml with minimal dependencies. Its C code is portable (no depext). The main OCaml dependencies are fmlib-parse and spawn.
  • Language agnostic like Bazel/Buck2.
  • Repeatable builds (my made-up term for a weak form of reproducible builds).
  • Lua scripting for build rules. The Lua implementation is pure OCaml and extends Lua-ML (thanks @lindig et al). In dk0 Lua plays the same role as Starlark in Bazel and Buck2.
  • Dynamic dependencies. This is somewhat esoteric for build systems but important for some languages (OCaml, C++20).
  • Single file scripts. Think uv but for arbitrary languages.
  • Multi-platform federated binary caching with indexed downloads. Think nix binary package caching, but each package can do its own caching in GitHub Actions / etc.
  • Attestations (security)

But repeatable builds means repackaging common system packages (git, tar, etc.) and providing build rules for compilers (msvc, clang, ocamlopt, etc.). That is a difficult, time-consuming assignment, especially when packaging for multiple operating systems (Windows, macOS and Linux).

Status:

  • dk0 is ready enough for making useful packages. However, a few backwards incompatible changes still need to be made and that might require tweaks to packages.
  • Today I have a couple packages; realistically there needs to be 20-30 packages to be useful. OCaml in particular will need a lot of packages that do not exist today.
  • When I complete a new package I’ll post an [ANN] similar to new opam packages.

Docs:

On the “site” link above you’ll see an example for a single-file script with C# / .NET … that example exists because I needed the script but more importantly because .NET has minimal transitive dependencies. If development goes well I’ll replace that with a more useful example that builds a Windows OCaml executable on macOS/Linux (using build rules that download/run wine, msvc, etc.).

If you are interested in contributing packages, I can setup video or audio time to get you or a group started quickly.

Lastly, I happen to like Dune (especially its watch mode) and the simplicity of Alice. Obviously I wouldn’t have made dk0 if I didn’t need to go beyond what exists today, but dk0 is open-source (libraries are Apache-2.0, executable is OSL-3.0) … I hope libraries can be shared across the different build systems! And because dk0 has dynamic dependencies, it is straightforward for dk0 to wrap other build systems (that is what I did with the .NET build system).

Thanks, Jonah

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[ANN] [dk0] CMake, Ninja and Google or-tools packages