improve shell.nix #675

	name: build-fedora
	on:
	pull_request:
	branches:
	- main
	push:
	branches:
	- main
	jobs:
	build:
	runs-on: ubuntu-latest
	container:
	image: fedora:latest
	options: --user root
	steps:
	- name: test
	run: \|
	set -x

	# GitHub sucks
	export HOME=/root
	cd $HOME

	# Install basic dependencies
	dnf update -y
	dnf install -y ca-certificates sed gzip grep git wget tar xz opam lld llvm

	git clone https://github.com/${{ github.repository }}.git
	cd $(basename ${{ github.repository }})

	if [ "${{ github.event_name }}" = "pull_request" ]; then
	git fetch origin pull/${{ github.event.pull_request.number }}/head:pr-${{ github.event.pull_request.number }}
	git checkout pr-${{ github.event.pull_request.number }}
	else
	git checkout ${{ github.ref_name }}
	fi

	# Prepare OCaml stuff
	opam init --disable-sandboxing --bare -ya
	opam switch create ocaml ocaml-base-compiler --criteria="-notuptodate"
	eval "$(opam env)"
	export OPAMCONFIRMLEVEL=unsafe-yes
	opam update

	# Install system and opam-repo dependencies
	opam install . --depext-only --with-test
	opam install . --deps-only --with-test

	# Rustup
	# TODO: it seems there is a rust-std-static-wasm32-unknown-unknown package now, maybe we could replace rustup and use it instead?
	rustup target add wasm32-unknown-unknown

	# Build and test
	dune build @install
	dune build @quicktest

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