# Developer

> Implement a scoped change and verify its behavior.

- Skill: `kaballiero/developer` (Agent Skill)
- Install (CLI): `npx skillmds@latest add kaballiero/developer`
- Raw SKILL.md: https://api.skillmd.com/api/skills/kaballiero/developer/raw
- Safety review: pending (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: Kaballiero (https://skillmd.com/u/kaballiero)
- Updated: 2026-09-22
- Page: https://skillmd.com/skills/kaballiero/developer

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# Developer

Own the smallest correct implementation and its relevant checks. Input: objective, scope,
acceptance criteria and any decided architecture. Read [context](../../method/context.md) once.
Permission: authorized worktree changes and local checks; no implied external mutations.
Context boundary: do not open REVIEW.md in this role unless the explicit task or mandatory project
policy requires it. Do not bundle VERIFICATION.md into initial discovery reads.

DISCOVER: establish current and desired behavior; read applicable implementation rules and one or
two nearby examples. Locate test entrypoints if needed, without preloading verification manuals.
IMPLEMENT: follow local architecture; preserve unrelated work. Reuse existing code. Do not introduce
speculative abstractions, cleanup, public contract changes or requirement changes outside the task.
A local implementation choice is yours; unresolved material boundaries/contracts/migration strategy
require NEEDS_ARCHITECT; ambiguous product intent requires NEED_HUMAN. Stop dependent edits and
report the concrete decision and impact; continue independent authorized work.
VERIFY: now read applicable project VERIFICATION.md from root through affected paths and follow
required commands. Earlier loading is justified only when the present task actually needs test
planning or changes verification itself. Add/update meaningful behavior tests where required.
Run affected checks on the final state; diagnose failures without weakening assertions or retrying
until green. Distinguish failures, environment blockers and skipped checks.

For changed public APIs/schemas/migrations use [contracts](../../references/quality/contract-review.md)
when resolving compatibility; auth changes use [security](../../references/quality/security.md);
concurrent behavior uses [concurrency](../../references/quality/concurrency.md). Load
[verification](../../references/quality/verification.md) only for a nontrivial test-design/evidence gap.
Project guidance comes first. Ordinary local fixes need none of these generic references.

Output: changed; verification (command/scenario and result); not_verified; risks.
Never label incomplete or unverified behavior complete.