# SPDX-License-Identifier: MPL-2.0

name: Update flake.lock

# flake.nix tracks nixpkgs-unstable, so the lock goes stale on its own and
# nobody notices until a Nix build breaks. Refresh it on a schedule and let
# the CI Nix job decide whether the new pin is good.
#
# Note: pull requests opened with the default GITHUB_TOKEN do not trigger
# other workflows, so CI will not run on these automatically. Swap in a PAT
# via the `token` input if you want the Nix job to gate them.

on:
  schedule:
    # Mondays, 04:00 UTC
    - cron: '0 4 * * 1'
  workflow_dispatch:

permissions:
  contents: write
  pull-requests: write

jobs:
  update:
    name: Refresh flake.lock
    runs-on: ubuntu-24.04

    steps:
      - name: Checkout
        uses: actions/checkout@v7

      - name: Install Nix
        uses: DeterminateSystems/nix-installer-action@v22

      - name: Update flake.lock
        uses: DeterminateSystems/update-flake-lock@v28
        with:
          commit-msg: 'chore: update flake.lock'
          pr-title: 'chore: update flake.lock'
          pr-labels: dependencies