V-Model Extension Pack for Spec Kit

The Compliance Chasm

Software engineering is split in two. AI-native teams ship features in hours — but produce no traceability, no test plans, and no proof of correctness. Regulated teams in medical devices, automotive, and aerospace have full traceability — maintained manually across spreadsheets and ALM platforms at the cost of weeks per feature.

Neither side wins.

	AI-Native Teams	Regulated Teams
Speed	Hours per feature	Weeks per feature
Traceability	None	Manual, error-prone
Audit readiness	Not applicable	Months of prep
Requirement coverage	Unknown	Manually verified
Cost of change	Low (code only)	Extreme (documentation)

Fast teams ship without proof of correctness. Compliant teams move too slowly to compete. What if rigor and velocity could coexist?

---

The Solution

The V-Model Extension Pack for Spec Kit closes this chasm. From a single specification, it generates traceable requirements, paired test plans, hazard analysis, and a deterministic traceability matrix — in minutes, not months.

The Core Principle

The AI drafts. The human decides. The scripts verify. Git remembers.

Scripts handle all deterministic logic — coverage calculations, matrix generation, gap detection. AI handles creative translation — turning specifications into structured requirements and test scenarios. Humans review every artifact before it enters the verified baseline.

graph LR
    REQ["<b>Requirements</b>"] ---|Matrix A| ATP["<b>Acceptance Testing</b>"]
    SYS["<b>System Design</b>"] ---|Matrix B| STP["<b>System Testing</b>"]
    ARCH["<b>Architecture</b>"] ---|Matrix C| ITP["<b>Integration Testing</b>"]
    MOD["<b>Module Design</b>"] ---|Matrix D| UTP["<b>Unit Testing</b>"]
    IMPL["<b>Implementation</b>"]

    REQ --> SYS --> ARCH --> MOD --> IMPL
    IMPL --> UTP --> ITP --> STP --> ATP

    style REQ fill:#4a86c8,color:#fff
    style ATP fill:#4a86c8,color:#fff
    style SYS fill:#5a9bd5,color:#fff
    style STP fill:#5a9bd5,color:#fff
    style ARCH fill:#70b0e0,color:#fff
    style ITP fill:#70b0e0,color:#fff
    style MOD fill:#8dc6e8,color:#000
    style UTP fill:#8dc6e8,color:#000
    style IMPL fill:#f0ad4e,color:#000

---

Key Features

14 Commands Across the Full V-Model

From requirements to audit reports — every V-Model level is covered with dedicated commands for specification, design, testing, and verification.

4 V-Model Levels

Progressive traceability from the top of the V to the bottom:

• Requirements ↔ Acceptance Testing — REQ-NNN → ATP-NNN-X → SCN-NNN-X#
• System Design ↔ System Testing — SYS-NNN → STP-NNN-X → STS-NNN-X#
• Architecture ↔ Integration Testing — ARCH-NNN → ITP-NNN-X → ITS-NNN-X#
• Module Design ↔ Unit Testing — MOD-NNN → UTP-NNN-X → UTS-NNN-X#

5 Traceability Matrices

• Matrix A — Requirements ↔ Acceptance
• Matrix B — System Design ↔ System Testing
• Matrix C — Architecture ↔ Integration Testing
• Matrix D — Module Design ↔ Unit Testing
• Matrix H — Hazard ↔ Mitigation Traceability

Hazard Analysis

ISO 14971 / ISO 26262 FMEA registers with operational state awareness, mitigation traceability, and automatic Matrix H generation.

Impact Analysis

Deterministic change impact tracing — identify every suspect artifact affected by a change, downward, upward, or both across the entire V-Model.

Peer Review

AI-powered stateless linter for any V-Model artifact. Evaluates against INCOSE, IEEE 1016/42010, ISO 29119, and ISO 14971 criteria. Produces PRF-{ARTIFACT}-NNN findings with CI-compatible exit codes.

Test Results Ingestion

100% deterministic JUnit XML and Cobertura XML ingestion. Updates the traceability matrix in-place — flipping ⬜ Untested to ✅ Passed / ❌ Failed / ⏭️ Skipped with Date, Commit SHA, and Coverage columns.

Audit Reports

Point-in-time release audit report: artifact inventory pinned to Git SHAs, traceability matrices, coverage analysis, hazard management summary, anomaly/waiver cross-referencing, and compliance gating.

---

Built for Regulated Industries

Medical Devices — IEC 62304 & FDA 21 CFR Part 820

Medical device software requires complete traceability between requirements, architecture, and verification evidence. A single requirement change can cascade into days of rework across multiple documents.

With V-Model Extension Pack: Generate traceable REQ-NNN items, paired ATP-NNN-X test cases, and SCN-NNN-X# BDD scenarios. The traceability matrix updates in seconds, not days. Coverage is verified by deterministic scripts — mathematically correct, not AI-assessed.

Automotive — ISO 26262

ISO 26262 demands traceability proportional to ASIL level. ASIL-D systems require the most rigorous evidence — orphaned tests or untested requirements are audit findings.

With V-Model Extension Pack: The three-tier ID schema creates self-documenting lineage. The matrix explicitly flags orphaned test cases and uncovered requirements. Deterministic validation scripts provide the mathematical proof that assessors require.

Aerospace — DO-178C

DO-178C requires bidirectional traceability: forward (requirement → test) and backward (test → requirement). Certification authorities expect this traceability to be demonstrably complete.

With V-Model Extension Pack: The /speckit.v-model.trace command produces both forward and backward traceability views in a single matrix. Gaps are surfaced immediately — before a DER review, not during one.

---

How It Works

The V-Model Extension Pack follows a progressive workflow. Each command produces artifacts in specs/{feature}/v-model/, and the traceability matrix is rebuilt after each design↔test pair to catch gaps early.

Step 1:  /speckit.specify                        →  Define your feature
Step 2:  /speckit.v-model.requirements           →  REQ-NNN from spec.md
Step 3:  /speckit.v-model.acceptance             →  ATP + SCN (100% coverage validated)
Step 4:  /speckit.v-model.trace                  →  Matrix A
Step 5:  /speckit.v-model.system-design          →  SYS-NNN (IEEE 1016 views)
Step 6:  /speckit.v-model.system-test            →  STP/STS (ISO 29119-4)
Step 7:  /speckit.v-model.hazard-analysis        →  HAZ-NNN (ISO 14971/26262 FMEA)
Step 8:  /speckit.v-model.trace                  →  Matrix A + B + H
Step 9:  /speckit.v-model.architecture-design    →  ARCH-NNN (IEEE 42010/4+1)
Step 10: /speckit.v-model.integration-test       →  ITP/ITS (ISO 29119-4)
Step 11: /speckit.v-model.trace                  →  Matrix A + B + C + H
Step 12: /speckit.v-model.module-design          →  MOD-NNN (pseudocode + state machines)
Step 13: /speckit.v-model.unit-test              →  UTP/UTS (white-box techniques)
Step 14: /speckit.v-model.trace                  →  Matrix A + B + C + D + H

After CI, ingest test results and generate the release audit report:

/speckit.v-model.test-results --input results.xml    →  ⬜ → ✅/❌/⏭️
/speckit.v-model.audit-report                        →  release-audit-report.md

At any time, run impact analysis or peer review:

/speckit.v-model.impact-analysis --downward REQ-001  →  Suspect artifacts + blast radius
/speckit.v-model.peer-review requirements.md         →  PRF-REQ-NNN findings

Progressive Traceability

The /speckit.v-model.trace command is run after each design↔test pair. Coverage gaps are caught at each V-level — not discovered at the end.

Output Structure

Every artifact lives in plaintext Markdown, versioned in Git:

specs/{feature}/v-model/
├── requirements.md              →  REQ-NNN requirements
├── acceptance-plan.md           →  ATP + SCN test cases
├── system-design.md             →  SYS-NNN components
├── system-test.md               →  STP/STS procedures
├── hazard-analysis.md           →  HAZ-NNN hazards (FMEA register)
├── architecture-design.md       →  ARCH-NNN modules
├── integration-test.md          →  ITP/ITS procedures
├── module-design.md             →  MOD-NNN detailed modules
├── unit-test.md                 →  UTP/UTS unit test procedures
├── peer-review-{artifact}.md    →  PRF-NNN findings (advisory)
├── traceability-matrix.md       →  Matrix A + B + C + D + H
└── release-audit-report.md      →  Point-in-time audit package

---

Get Started

• Get Started

  ---

  Install the extension and generate your first traceable specification in minutes.

  Getting started

• Read the Docs

  ---

  Learn the concepts, commands, and architecture behind the V-Model Extension Pack.

  Concepts guide

• About & Philosophy

  ---

  Understand the architectural decisions and separation of concerns that make this tool trustworthy.

  About