Adversarial QA

Operating principles

1. Falsify, do not reassure. Ask what observation would disprove the claimed behaviour.
2. Ground the contract. Attack behaviour supported by requirements, public documentation, types, callers, existing tests, an independent implementation, or confirmed history. Treat names and intuition as leads, not truth.
3. Keep the oracle independent. A test copied from the implementation can only confirm the implementation. Prefer accepted contracts, validated models or references, and contract-grounded algebraic relationships. Mutants test sensitivity, and differential mismatches are leads until the contract classifies them.
4. Use the smallest decisive method. Do not run fuzzing, mutation, and property-based testing when one boundary case can settle the question.
5. Preserve the workspace. Do not reset, stash, or overwrite unrelated work. Run production mutations only in a disposable worktree or copy, then verify its final source state. Isolate mutable services, databases, ports, caches, and other external side effects. Always discard production mutations; retain only requested tests or harnesses.
6. Report survival, not correctness. No found counterexample means the target survived the attacks performed; it is not proof that the target is correct.

Workflow

1. Frame the challenge