Does it require a previous step to run?

Yes, this is Step 2 of the StackShift process. It requires a valid .stackshift-state.json file generated by the initial analysis step to understand the project structure and selected route.

How do Greenfield and Brownfield routes differ?

The Greenfield route extracts pure business logic while remaining framework-agnostic, ideal for rewrites. The Brownfield route captures both business logic and specific technical implementation details for maintaining existing systems.

What documentation files does this skill generate?

It generates 11 files: functional specs, integration points, configuration reference, data architecture, operations guide, tech debt analysis, observability requirements, visual design system, test documentation, business context, and decision rationale.

How does 'Decision Archaeology' work?

It analyzes dependency manifests, config files, git blame data, and code comments (like TODO or HACK) to reconstruct the history and reasoning behind previous engineering decisions.

Reverse Engineer (StackShift)

Name: Reverse Engineer (StackShift)
Author: jschulte

byjschulte

•

Learning & Documentation

Performs deep codebase analysis to generate eleven comprehensive documentation files for legacy system understanding and migration.

The Reverse Engineer skill is a powerful tool designed to bridge the gap between existing codebases and new development specs. It performs an exhaustive multi-phase analysis of backend, frontend, infrastructure, and testing layers to produce 11 structured markdown files. By supporting both 'Greenfield' (logic-only) and 'Brownfield' (logic + technical) routes, it allows teams to extract either pure business requirements or full implementation details. It even includes 'Decision Archaeology' to uncover the hidden reasoning behind architectural choices, making it indispensable for system migrations and onboarding.

Key Features

01State-managed workflow that integrates with the StackShift spec-driven development process.

02Route-aware extraction: switch between tech-agnostic and tech-prescriptive documentation.

03Decision Archaeology to identify 'why' architectural choices were made via git history and comments.

041 GitHub stars

05Deep analysis sub-agents for API mapping, data modeling, and infrastructure auditing.

06Automated generation of 11 core documents including functional specs and technical debt analysis.

Use Cases

01Documenting undocumented legacy systems before a cloud migration or framework rewrite.

02Accelerating developer onboarding by providing a complete map of architecture, data flow, and tech debt.

03Extracting framework-agnostic business logic from an existing app for a greenfield rebuild.

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add jschulte/claude-plugins reverse-engineer

For use in Claude.ai and ChatGPT

Download Skill