implement

name	implement
description	Implement features, fix bugs, and modify production source code in S3Mock. Use when asked to add functionality, change behavior, or modify source files in server/, integration-tests/, or testsupport/. Not for documentation-only or test-only changes. Orchestrates lint, test, and document skills as part of the complete workflow.

Implementation Skill

Entry Criteria

Use this skill when asked to:

• Add a new S3 API operation or sub-feature
• Fix a bug in production code
• Modify existing source files in server/, integration-tests/, or testsupport/

Not for test-only or documentation-only changes — use the test or document skill instead.

Before Starting

1. Read AGENTS.md (root) and the relevant module AGENTS.md (server/AGENTS.md, integration-tests/AGENTS.md, or testsupport/AGENTS.md).
2. Identify the AWS S3 API operation — verify element names and behavior against the AWS S3 API docs.
3. Review existing similar implementations for patterns to follow.
4. If nearby code would benefit from cleanup before adding new code, invoke the refactor skill first.

Execution Steps

New S3 Operations: DTO → Store → Service → Controller

Follow this order exactly — do not skip layers or add logic in the wrong layer:

1. DTO (server/.../dto/): Create data classes with Jackson XML annotations. Verify element and attribute names match the AWS S3 API specification exactly — see INVARIANTS.md. A compile check is not sufficient; run integration tests to verify serialized output.
2. Store (server/.../store/): Add filesystem operations. Follow existing patterns for binary data and metadata JSON.
3. Service (server/.../service/): Add business logic and validation. Throw S3Exception constants only — see INVARIANTS.md.
4. Controller (server/.../controller/): Add HTTP mapping only. Delegate all logic to services. Controllers never catch exceptions — see INVARIANTS.md.

All Changes

• Update the copyright year to 2017-<current year> in the license header of every file you modify — see INVARIANTS.md.
• Invoke the lint skill after implementation to fix formatting and verify style gates.
• Invoke the test skill to add or update unit and integration tests.
• Invoke the document skill to update CHANGELOG.md, README.md, and AGENTS.md where applicable.

Completion Criteria

• Code compiles (make skip-docker)
• Unit tests pass (make test)
• Integration tests pass (make integration-tests)
• Lint gates pass (via lint skill)
• Copyright year updated in every modified file
• Tests added or updated (via test skill)
• Docs updated (via document skill)

Troubleshooting

• Build fails: Check JDK 25 is active; run make format and fix remaining lint errors.
• Tests fail on XML: Verify element names match the AWS S3 API exactly — a compile check is insufficient. Run integration tests to confirm serialized output.
• Docker fails: Use make skip-docker to isolate the build from Docker issues.

Resources

• AGENTS.md — architecture, DO/DON'T, build commands
• INVARIANTS.md — hard constraints (copyright, SDK version, XML naming, layering rules)
• Relevant module AGENTS.md (server/AGENTS.md, integration-tests/AGENTS.md, or testsupport/AGENTS.md)
• docs/KOTLIN.md — Kotlin idioms and naming conventions
• docs/SPRING.md — Spring Boot patterns, DI, exception handling