add actions for checks / builds #9

	name: Nix CI
	on:
	push:
	# don't run on tags, run on commits
	# https://github.com/orgs/community/discussions/25615
	tags-ignore:
	- "**"
	branches:
	- main
	pull_request:
	workflow_dispatch:

	env:
	# We want the cache to be as full as possible, so we instruct nix to keep derivations
	# and other related outputs around in its cache
	nix_conf: \|
	keep-env-derivations = true
	keep-outputs = true

	jobs:
	check:
	name: Run checks
	runs-on: ubuntu-24.04
	permissions:
	actions: write
	contents: read
	steps:
	- uses: actions/checkout@v4
	with:
	ref: ${{ github.event.pull_request.head.sha }}
	- uses: nixbuild/nix-quick-install-action@v30
	with:
	nix_conf: ${{ env.nix_conf }}
	- name: Restore and save Nix store
	uses: nix-community/cache-nix-action@v6
	with:
	primary-key: build-${{ runner.os }}-${{ hashFiles('Cargo.lock', '**/Cargo.toml', 'flake.nix', 'flake.lock', 'rust-toolchain.toml') }}
	purge: true
	purge-prefixes: build-${{ runner.os }}-
	purge-created: 0
	purge-primary-key: never
	gc-max-store-size: 5G
	- name: Run checks
	run: nix flake check

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