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Dev partition flakes with empty outputs are a recurring pattern problem

Problem

Dev partition flakes (dev/flake.nix) are frequently created with empty outputs:

outputs = _: { };

This means the dev partition exists structurally but contributes nothing — no CI generation, no dev tooling, no child pipelines. The partition is a no-op.

This has been flagged as a recurring problem by @locallycompact, most recently on nix/hackage-server-module!2 (merged).

Impact

  • Dev partitions that don't generate child pipelines defeat the purpose of the partition architecture
  • CI may pass without actually testing anything meaningful from the dev partition
  • The pattern propagates across repos as developers copy from existing migrations

Expected Behaviour

Dev partition flakes should have meaningful outputs that at minimum enable CI generation through the gitlab-ci input. The mkPartitionModule in nix/partitions/dev.nix relies on the dev flake having proper structure.

Proposed QC Policy Addition

  1. Dev partition flakes MUST NOT have empty outputs — QC should flag outputs = _: { }; in any dev/flake.nix as a defect
  2. Document the correct dev partition output pattern as a reference for @smartypants and other contributors
  3. Add this check to the daily audit

Affected Repos (known)

  • nix/hackage-server-module (current, MR !2 (merged))
  • Potentially any future nixica migration