https://github.com/JRMurr/roc2nix

Nix builder for roc code
https://github.com/JRMurr/roc2nix

nix nixos roc-lang

Last synced: about 2 months ago
JSON representation

Nix builder for roc code

• Host: GitHub
• URL: https://github.com/JRMurr/roc2nix
• Owner: JRMurr
• Created: 2023-11-23T05:09:25.000Z (10 months ago)
• Default Branch: main
• Last Pushed: 2023-12-30T00:20:36.000Z (9 months ago)
• Last Synced: 2024-02-12T15:19:48.102Z (7 months ago)
• Topics: nix, nixos, roc-lang
• Language: Nix
• Homepage:
• Size: 86.9 KB
• Stars: 10
• Watchers: 2
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md

Awesome Lists containing this project

• roc-awesome - JRMurr/roc2nix

README

        
# roc2Nix

Very much a work in progress but basic nix building works

to run the example you can run `nix build .#examples-simple --print-build-logs` in the repo root

## Quick start

See [this example](./templates/quick-start/) for a simple roc app taken form [roc-parser](https://github.com/lukewilliamboswell/roc-parser/blob/main/examples/letters.roc) which builds a roc binary using 2 external deps

you can run the following to copy the template into your current folder

```shell

 nix flake init --template github:JRMurr/roc2nix#quick-start --refresh

```

## How it works

NOTE: goal is to eventually have a code gen step to reduce boiler plate like node2nix but for now its all manaul

- nix is given a list of urls of roc packages with their sha256 hash

- `downloadRocPackage` will call `fetchUrl` on each package and extract the package into a directory

- `mkRocDerivation` will replace all references to the package url with the now local path and build with the provided roc compiler

## TODO

- [ ] TLC around how roc deps are replaced by the nix store paths. Right now its basically a regex is fine for the long urls but for local file paths there is a potential for collisions

- [ ] actually verify the blake3 checksum. (since we untar roc wont do this for us). Maybe roc could support local tar balls?

- [ ] A code gen tool to get all deps of a roc package for you

## Ideas to explore

- Use the nix c abi to make a "nix platform" for roc. Potential for roc build to build the derivation or at least move more of this logic into roc.

- Expose an api to work with `evalModules` or `flakeParts` to make it easier to compose all the needed builds + have better input validation

Lib setup is heavily inspired by [crane](https://github.com/ipetkov/crane)

## notes

see https://github.com/JRMurr/roc/blob/3d8884a96d44e2101ce8932336b74e2b9416e029/crates/compiler/build/src/link.rs#L437 

for how roc calls out to compile different platforms