ghc-wasm32-wasi

This repo provides convenient methods of using x86_64-linux binary artifacts of our GHC wasm32-wasi port.

Getting started as a nix flake

The default output is a derivation that bundles all provided tools:

$ nix shell
$ wasm32-wasi-ghc --version
The Glorious Glasgow Haskell Compilation System, version 9.5.20220520

As a shell script

For Ubuntu 20.04 and similar glibc-based distros:

$ ./setup.sh
...
Everything set up in /home/runner/.ghc-wasm32-wasi.
Run 'source /home/runner/.ghc-wasm32-wasi/env' to add tools to your PATH.

Set PREFIX environment variable to customize where to set up things. Set BIGNUM_BACKEND to gmp/native to specify the ghc-bignum backend. The script requires curl and unzip to run.

Provided tools

• wasi-sdk
• wasm32-wasi-ghc
• wasm32-wasi-cabal: A cabal wrapper that automatically uses wasm32-wasi-ghc, and builds stuff in an isolated cabal store to avoid interfering with host cabal.
• wasmtime
• wasmtime-run
• binaryen
• wabt

wasmtime-run

wasmtime-run requires proot to be installed (in the non-nix version). It enables you to run ELF/wasm hybrid apps, using wasmtime as the wasm execution engine, as long as the wasm file has set the execution bit.

$ wasmtime-run ./some-wasm.wasm arg1 arg2
$ wasmtime-run wasm32-wasi-cabal run target

See this blog post for implementation details.