Language policy: scripts/abi-ffi-gate.py is Python (banned) — migrate or document an exemption #170

Summary

The governance / Language / package anti-pattern policy job fails on verisimiser (seen on PR #167, run 28286708330). Pre-existing — scripts/abi-ffi-gate.py is a Python file, and Python is fully banned estate-wide. Surfaced here for the master scheduler. (I added zero .py files in PR #167; this predates it.)

What the check reports (verbatim)

❌ Python files detected - Python is fully banned — use AffineScript/Rust/SPARK/Julia (SaltStack carveout removed 2026-01-03)
scripts/abi-ffi-gate.py
   (declare an exemption via .hypatia-ignore or an inline
    '# hypatia:ignore cicd_rules/banned_language_file' pragma if intentional)

Options

1. Migrate (policy-preferred). Rewrite scripts/abi-ffi-gate.py in an allowed language — Bash/POSIX (it's a CI gate script, likely a good fit), or Rust/Julia/AffineScript — and update any workflow/recipe that invokes it. Per CLAUDE.md, "Python is fully banned, no exceptions," so migration is the policy-correct path.
2. Document an exemption (only if migration is genuinely blocked): add a .hypatia-ignore entry or an inline # hypatia:ignore cicd_rules/banned_language_file pragma with a rationale + unblock condition. This is a policy decision for the owner, not something to apply unilaterally.

Proposed actions

• Decide migrate vs. exempt (owner).
• If migrate: port scripts/abi-ffi-gate.py → Bash/Rust/Julia and rewire its caller; verify the ABI↔FFI gate still works.
• If exempt: add the documented exemption with rationale + unblock condition.

Scope note

Likely a one-off in this repo, but if other -iser repos carry the same abi-ffi-gate.py, prefer a shared migration tracked in hyperpolymath/standards.

Filed from a Claude Code cloud session as a follow-up to PR #167 (merged). Surfaced for the master scheduler.