v0.4.0 — Multi-Domain Engineering

v0.4.0 — Multi-Domain Engineering

Date: 2026-03-29
Release type: Minor
Summary: PromptKit expands beyond software into hardware engineering (electrical, firmware), protocol engineering, and library self-auditing — adding 40 new components with three new personas, a hardware-lifecycle pipeline, and quantitative validation capabilities.

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Highlights

• ⚡ Electrical engineering domain — First non-software domain: an electrical-engineer persona, 4 analysis protocols (schematic compliance, BOM consistency, layout review, simulation validation), 4 review templates, and a new hardware-lifecycle pipeline that chains requirements → schematic → simulation → BOM → layout review. (#97, #100, #102)
• 🔌 Embedded firmware persona — embedded-firmware-engineer for boot sequences, recovery flows, OTA update analysis, and bare-metal firmware audit, paired with spec-invariant-audit for specification-level verification. (#85)
• 📡 Protocol engineering — protocol-architect persona with templates for evolving protocols, analyzing conflicts between specifications, designing validation suites, and diffing specification versions, plus two new formats (protocol-delta, protocol-validation-spec) and a protocol-change-categories taxonomy. (#84, #89)
• 📐 Interface contracts & quantitative validation — New interface-contract format for HW↔FW, service↔service, and library↔consumer boundaries with authoring and audit templates; plus validate-budget for margin analysis and sensitivity checks on power, timing, and memory budgets. (#98, #99)
• 🔍 Library self-auditing — audit-library-consistency template enables PromptKit to audit its own component consistency; its first run identified and fixed 18 findings across two PRs. (#101, #103, #105)

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Breaking Changes

No breaking changes in this release.

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Changelog

Added

Personas (+3)

• electrical-engineer — First non-software persona; circuit/PCB/power-system analysis. (#97)
• embedded-firmware-engineer — Boot, recovery, OTA, and bare-metal firmware analysis. (#85)
• protocol-architect — RFC/internet-draft design, protocol evolution, and interoperability analysis. (#84)

Protocols (+12)

Analysis:

• schematic-compliance-audit — Systematic schematic review against requirements and datasheets. (#97)
• bom-consistency — BOM cross-reference validation against schematics and requirements. (#102)
• layout-design-review — PCB layout review for trace widths, impedance, placement, and DRC. (#102)
• simulation-validation — Verify simulation setup, results, corner coverage, and model validity. (#100)

Reasoning:

• spec-invariant-audit — Adversarial analysis of specifications against user-supplied invariants. (#85)
• spec-evolution-diff — Structured semantic diff of specification versions. (#89)
• protocol-evolution — Model protocol version transitions and backward-compatibility impact. (#84)
• protocol-conflict-analysis — Detect conflicts and ambiguities between protocol specifications. (#84)
• protocol-validation-design — Design validation suites for protocol conformance testing. (#84)
• interface-contract-audit — Audit interface contracts for completeness, consistency, and testability. (#98)
• quantitative-constraint-validation — Budget validation with margin analysis and sensitivity. (#99)
• session-profiling — Profile LLM session performance patterns and bottlenecks. (#72)

Templates (+18)

Hardware engineering:

• review-schematic — Schematic compliance review against requirements and standards. (#97)
• review-bom — BOM consistency and availability review. (#102)
• review-layout — PCB layout design review for manufacturability and signal integrity. (#102)
• validate-simulation — Simulation methodology and results validation. (#100)
• validate-budget — Quantitative budget validation (power, timing, memory) with margin analysis. (#99)

Protocol engineering:

• evolve-protocol — Draft protocol evolution proposals with migration analysis. (#84)
• analyze-protocol-conflicts — Detect and resolve conflicts between protocol specifications. (#84)
• author-protocol-validation — Design protocol validation/conformance test suites. (#84)
• diff-specifications — Generate structured diffs between specification versions. (#89)

Specification & modeling:

• audit-spec-invariants — Audit specification invariants and constraints. (#85)
• reconstruct-behavior — Extract state machines and behavioral models from engineering artifacts. (#95)
• author-rfc — Author internet-drafts in xml2rfc v3 format. (#90)
• author-architecture-spec — Generate architecture specification documents. (#83)

Interface contracts:

• author-interface-contract — Author interface contracts for HW↔FW, service↔service, or library↔consumer boundaries. (#98)
• audit-interface-contract — Audit interface contracts for completeness and consistency. (#98)

Library tooling:

• audit-library-consistency — Self-audit PromptKit's own component consistency. (#101)
• classify-findings — Classify diagnostic findings against known pattern catalogs. (#105)

Session analysis:

• profile-session — Profile and analyze LLM session interactions for optimization. (#72)

Formats (+6)

• interface-contract — Structured boundary contracts for HW↔FW, service↔service, and library↔consumer interfaces. (#98)
• behavioral-model — State machine and behavioral model extraction output. (#95)
• rfc-document — xml2rfc v3 format for authoring internet-drafts and RFCs. (#90)
• architecture-spec — Architecture specification documents. (#83)
• protocol-delta — Structured protocol version diff output. (#84)
• protocol-validation-spec — Protocol validation suite specification. (#84)

Taxonomies (+1)

• protocol-change-categories — Classification categories for protocol evolution changes. (#84)

Pipelines (+1)

• hardware-lifecycle — Spec-first hardware design lifecycle: requirements → schematic review → simulation validation → BOM review → layout review. (#97, #100, #102)

Changed

• review-cpp-code — Added cpp-review-patterns taxonomy. (#103)
• CONTRIBUTING.md — Defined applicable_to semantics. (#105)
• 3 formats — Added Confidence Framework documentation. (#105)
• 5 protocols — Fixed applicable_to cross-references. (#103)
• 1 taxonomy — Added missing applicable_to field. (#103)

Fixed

• Phantom applicable_to reference in finding-classification protocol. (#87)
• [ASSUMED] → [ASSUMPTION] terminology drift across 5 files. (#103)
• 18 consistency audit findings (F-001 through F-018) fixed. (#103, #105)

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Upgrade Instructions

cd promptkit
git fetch origin
git checkout v0.4.0    # or: git pull origin main
python tests/validate-manifest.py  # verify

No breaking changes — existing prompts continue to work unchanged.

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Contributors

• @Alan-Jowett — Electrical engineering domain, protocol engineering, firmware persona, interface contracts, quantitative validation, behavioral models, RFC authoring, library self-auditing, architecture specs, consistency audit fixes
• @themechbro — Session profiling protocol and template (#72) — first external contribution 🎉

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Stats

	v0.3.0	v0.4.0	Delta
Personas	10	13	+3
Protocols	32	44	+12
Templates	36	54	+18
Formats	14	20	+6
Taxonomies	4	5	+1
Pipelines	1	2	+1
Total	96	136	+40

Full Changelog: v0.3.0...v0.4.0