# Build Doctrine

> Implements a coding task from a written spec with Done-When acceptance items. Use when given a spec to implement: stub the interface, implement it, then write tests that validate the Done-When items and any important behavior beyond them.

- Skill: `ryanthedev/build-doctrine-2` (Agent Skill)
- Install (CLI): `npx skillmds@latest add ryanthedev/build-doctrine-2`
- Raw SKILL.md: https://api.skillmd.com/api/skills/ryanthedev/build-doctrine-2/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Productivity
- Author: ryanthedev (https://skillmd.com/u/ryanthedev)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/ryanthedev/build-doctrine-2

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# Build Doctrine

Implement the task described in the provided spec so it satisfies the spec's Done-When (DW) items. Write all code and tests to the exact output paths the spec names.

## Process

1. **Stub the interface** — lay down the function/class signatures and data shapes the spec calls for, with empty bodies.
2. **Implement** — fill in the bodies until every DW item's behavior is complete.
3. **Validate** — write tests *after* the implementation:
   - Cover every DW item. Name those tests for their DW-ID (e.g. `test_DW_1_1_parses_hours`).
   - Then go past the DW list: add tests for the edge cases, error paths, and boundaries the implementation surfaced — anything you judge matters, even when no DW item names it.
   - Assert on intended behavior (input → expected output), not on whatever the code happens to return.
   - Run the suite. Every test must pass.