flake: pin nixpkgs to nixos-unstable #489

	name: CI

	on:
	push:
	branches: [main]
	pull_request:
	workflow_dispatch:

	jobs:
	build:
	name: Build outputs (${{ matrix.system }})

	strategy:
	matrix:
	include:
	- system: x86_64-linux
	os: ubuntu-latest

	runs-on: ${{ matrix.os }}

	steps:
	# https://github.com/actions/runner-images/issues/2840#issuecomment-790492173
	- name: Clear disk space
	run: \|
	sudo rm -rf /usr/share/dotnet
	sudo rm -rf /opt/ghc
	sudo rm -rf "/usr/local/share/boost"
	sudo rm -rf "$AGENT_TOOLSDIRECTORY"

	- name: Checkout repository
	uses: actions/checkout@v4

	- name: Install Nix
	uses: DeterminateSystems/nix-installer-action@v15
	with:
	diagnostic-endpoint: ""

	- name: Setup Cachix
	uses: cachix/cachix-action@v15
	with:
	name: getchoo
	authToken: ${{ secrets.CACHIX_AUTH_TOKEN }}

	- name: Run build
	env:
	SYSTEM: ${{ matrix.system }}
	run: \|
	nix run \
	github:Mic92/nix-fast-build -- \
	--no-nom \
	--skip-cached \
	--systems "$SYSTEM" \
	--option allow-import-from-derivation true \
	--flake '.#hydraJobs'

	build-gate:
	name: Build gate

	if: ${{ always() }}
	needs: build

	runs-on: ubuntu-latest

	steps:
	- name: Exit with error
	if: contains(needs..result, 'failure') \|\| contains(needs..result, 'cancelled')
	run: exit 1

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