CI workflow gates on nixfmt formatting and evaluates all three host toplevels (aarch64 evaluates without emulation; no full builds in CI).
renovate.json enables the nix manager and weekly lockFileMaintenance for flake.lock, plus grouped github-actions updates (Renovate matches .gitea/workflows). A self-hosted Renovate workflow runs it on Gitea, since Gitea has no built-in Renovate; it needs a RENOVATE_TOKEN secret.
Renovate Bot