Spec-Driven Development PoC

A proof-of-concept for spec-driven development: feature specs and tests are written by hand AI, and an AI agent generates the application code from them.

This repository goes hand-in-hand with this blogpost.

How it works

1. Specs (specs/) define the API — entities, endpoints, validation rules, and business rules
2. Tests (tests/) encode the expected behavior
3. Schema (schema/) defines the database structure
4. An AI agent reads these artifacts and generates all code in src/

The generated code is disposable — never committed, always regenerated from scratch.

Tech stack

• PHP 8.4, Symfony 8.0
• Doctrine ORM
• PHPUnit
• Docker Compose for local development

Project structure

specs/          Feature specs (source of truth for behavior)
tests/          PHPUnit tests (source of truth for correctness)
schema/         SQL schema (source of truth for data structure)
src/            Generated application code (not committed)