spec-driven-implementation

A spec-first workflow requires drafting a product spec to define user problems, success criteria, and UX impact before writing any code. This approach aligns product, design, and engineering teams on a shared contract to reduce ambiguity and rework.

To write a product spec before coding, draft a concise document describing the user problem, intended user experience, success criteria, and acceptance tests. This written spec establishes a shared contract for stakeholders before implementation begins.

You need a tech spec for architecture changes or cross-cutting initiatives when a feature warrants detailed technical planning. It accompanies the product spec to define structural implementation details before development across multiple subsystems begins.

You keep feature specifications updated by storing them in source control alongside the code. This practice encourages continuous updates as implementation evolves, ensuring the specs remain accurate and providing traceability during code review.

Spec-first implementation is designed for large features with multiple subsystems where stakeholders need a shared contract before coding. It enforces written product and tech specs to align teams and reduce risk across complex initiatives.

Writing product specs before implementation drives disciplined development by ensuring user problems and success criteria are defined upfront. This reduces ambiguity, minimizes rework, and aligns engineering teams before significant coding starts.