spec-first-sdlc

Convert user intent into a spec-first SDLC pipeline with phase gates.

1|Updated Dec 23, 2025
One-click install
npx skills add https://github.com/esxr/sdlc-skill --skill spec-first-sdlc
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: spec-first-sdlc
Source: https://github.com/esxr/sdlc-skill/tree/main/.
Command: npx skills add https://github.com/esxr/sdlc-skill --skill spec-first-sdlc

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

Spec-First SDLC provides a structured approach to transform human intent into traceable software artifacts. It reduces ambiguity, ensures design-before-code discipline, and provides a clear path from requirements to implemented software with review gates at each phase.

Core Features & Use Cases

  • Intent-to-design flow: Claude produces High-Level Design (HLD), ADR-Lite, and executable implementation specs from an initial intent document.
  • Traceability through artifacts: Links requirements to ADRs, design decisions, and implementation.
  • Code generation & validation: Generates code and tests from the EIS and validated outputs.
  • Use Case: A new project starts with a requirements document; the Skill guides through HLD, ADR-Lite, EIS, and code, with human reviews at each stage.

Quick Start

Prepare your Intent & Constraints document and optional design artifacts, then run this Skill. Claude will generate the High-Level Design, ADR-Lite, revised HLD, Executable Implementation Specification, and from that, code in src/ and tests in tests/. Review each phase before proceeding.

Frequently Asked Questions about spec-first-sdlc

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I convert requirements into traceable design artifacts before coding?

Spec-first SDLC transforms requirements into structured design artifacts—High-Level Design, ADR-Lite decisions, and Executable Implementation Specification—with human review gates at each phase, ensuring traceability from intent through implementation.

What is an ADR-Lite and why use it for architecture decisions?

ADR-Lite captures architecture decisions with context, rationale, and consequences in a lightweight format. It creates a traceable record linking design choices to requirements and code, reducing ambiguity and enabling future maintainers to understand the 'why' behind decisions.

Can I generate code automatically from design specifications?

Yes. The Spec-First SDLC pipeline generates executable code and tests directly from the validated Executable Implementation Specification, automating the translation from design intent to working implementation with built-in test coverage.

How do I ensure design-before-code discipline across my team?

Implement phase gates with mandatory human approval at Intent, HLD, ADR, and EIS stages. This enforces review discipline, prevents premature coding, and ensures requirements, architecture decisions, and implementation stay aligned throughout the project lifecycle.

What's the difference between spec-first and code-first development?

Spec-first development prioritizes design artifacts and requirements clarification before writing code, reducing rework and ensuring traceability. Code-first typically begins implementation immediately, risking design misalignment and incomplete documentation of architectural decisions.

Do I need existing design documents to use this workflow?

No. Start with an Intent & Constraints document describing your requirements and goals. The pipeline generates HLD, ADRs, and implementation specs from that starting point, though you can also provide optional existing design artifacts to build upon.