| name | test-matrix |
| description | Use when a project needs testing BEYOND unit tests — fuzzing, property-based, load, E2E, or mutation. Five-phase hub-and-spoke pipeline composes the right mix per language × critical path × CI target, scaffolds configs + corpus + fixtures, wires CI jobs, and defines the crash/regression triage workflow. Pure-click: every decision except intake is an AskUserQuestion. |
| argument-hint | <free-text description of what needs testing and why> |
/test-matrix — Testing beyond unit tests (index)
When to use
- A project needs testing beyond unit tests: fuzzing, property-based, load, E2E, or mutation testing.
- At project kickoff or when coverage gaps span multiple test paradigms across the stack.
- Use
/test-matrix for project-wide strategy; use /test-gen for per-function unit tests.
You are designing a testing matrix for a project that already has (or
should have) unit-test coverage via /test-gen. This skill owns the
orthogonal axes:
- Fuzzing — input-space exploration at boundaries (parsers, deserializers, crypto)
- Property-based — invariants verified over generated inputs (pure functions, data structures)
- Load — SLO assertion under traffic (
k6/vegeta/oha, baseline→profile→fix)
- E2E — browser-driven critical journeys (Playwright, page objects, trace viewer)
- Mutation — test-suite quality verification (mutmut / cargo-mutants / StrykerJS)
Not duplicated here: happy-path / edge / error unit tests (/test-gen
owns those). This skill links rather than re-implements.
This SKILL.md is the INDEX. Each phase lives in its own file, executed in
order. Never skip, never re-order.
Pipeline overview (5 phases + final report)
Minimum AskUserQuestion count across a full session: 5 (one per phase).
Higher when Phase 3 expands per selected cell. This is the pure-click
contract.
Variables the pipeline produces
| Name | Set in | Meaning |
|---|
LANGS | Phase 1 | Languages in scope (Rust / Python / JS-TS / Go / Swift / Flutter — multi) |
COVERAGE | Phase 1 | Baseline unit-test coverage % (or "unknown") |
CRITICAL | Phase 1 | Critical paths: auth / payment / data-integrity / perf / untrusted-input |
CI | Phase 1 | github-actions / forgejo-actions / self-hosted / none |
MATRIX | Phase 2 | Set of (test-type × language) cells to scaffold |
SCAFFOLDED | Phase 3 | Files written per cell (paths + corpus seeds) |
CI_JOBS | Phase 4 | CI workflow entries added per cell |
TRIAGE_DOC | Phase 5 | Path to docs/testing/triage.md (or project-local equivalent) |
Final report (emit after Phase 5)
=== TEST-MATRIX REPORT ===
Languages: <LANGS>
Coverage (unit): <COVERAGE>
Critical paths: <CRITICAL>
Matrix cells: <count> — <list (type × lang)>
Files written: <count> (configs + corpus + fixtures)
CI jobs added: <count> (<per-type failure policy>)
Triage doc: <TRIAGE_DOC>
Next action: Run <cmd> locally to verify the scaffold, then commit.
Rules (apply throughout)
- Pure-click contract. Only the Phase 1 intake paragraph is free text.
Everything else is
AskUserQuestion. Count in the final report.
- NO DOWNGRADE (RULE -1). If a language × type cell has no good tool,
return 2-3 constructive paths, never "not supported".
- NO HALLUCINATION (RULE 0.4). Every tool / library cited must exist
and be current. When in doubt, mark
[UNVERIFIED — verify release page]
and surface in the report.
- Plan Mode First (RULE 0.5). This skill IS the plan; no writes before
the corresponding phase's confirm click.
- Constructor Pattern (RULE ZERO). Block files (
_blocks/test-*.md)
stay ≤ 60 LOC. This SKILL.md ≤ 200 LOC; phase files ≤ 150 LOC each.
- Surgical Changes. Writes only to:
<repo>/tests/, <repo>/fuzz/, <repo>/e2e/, <repo>/load/<repo>/.github/workflows/ or <repo>/.forgejo/workflows/<repo>/docs/testing/triage.md- No writes to
_blocks/ here (that's compose-solution's Phase 6).
- No duplication with
/test-gen. If the user really wants unit-test
generation, Phase 1 detects it and hands off immediately.
References
- phase-1-intake.md · phase-2-matrix.md · phase-3-scaffold.md · phase-4-ci-wire.md · phase-5-triage.md
skills/test-gen/SKILL.md — unit-test generation (happy / edge / error).
Phase 1 hands off there if intake reveals unit-test gap, not matrix gap._blocks/test-fuzz.md · _blocks/test-property.md · _blocks/test-load.md · _blocks/test-e2e.md — per-paradigm reference blocks, composable into manifests._blocks/rule-test-first.md — TDD / tests-with-code discipline (inherited).skills/compose-solution/SKILL.md — if you need a NEW block (e.g. mutation-specific), hand off there (Phase 6 block-augment).
