backend-worker

name	backend-worker
description	Implements Hono API endpoints, database operations, and business logic with Bun/SQLite

Backend Worker

NOTE: Startup and cleanup are handled by worker-base. This skill defines the WORK PROCEDURE.

When to Use This Skill

Use for features involving:

• API endpoint implementation (REST routes with Hono)
• Database schema changes (migrations, tables)
• Business logic and validation
• Data models and repositories
• Backend testing

Work Procedure

1. Write tests first (RED) - Create test file in tests/ or alongside source

   • Use Bun's built-in test runner: bun test
   • Cover: happy path, validation errors, edge cases, database operations
   • Run bun test --watch to verify tests FAIL before implementing

2. Implement feature (GREEN) - Make tests pass

   • Follow existing patterns in src/ directory
   • Use Drizzle ORM for database operations
   • Validate inputs with Zod schemas
   • Add proper error handling and status codes

3. Manual verification

   • Start server: bun run dev
   • Test with curl or HTTP client
   • Verify database state with SQLite queries
   • Check logs for errors

4. Run validators

   • bun run typecheck - TypeScript validation
   • bun run lint - Code style
   • bun test - All tests must pass

5. Document API changes

   • Update API documentation if adding new endpoints
   • Include request/response examples

Example Handoff

{
  "salientSummary": "Implemented POST /api/tasks endpoint with Zod validation, created tasks table with Drizzle, added 5 tests covering creation, validation, and duplicate prevention.",
  "whatWasImplemented": "POST /api/tasks endpoint that accepts agent_id, project_id, title, description, task_type. Creates task in 'backlog' status. Returns 201 with created task. Returns 400 for invalid input. Returns 404 for non-existent project. Returns 409 for duplicate task title in same project. Added tasks table migration with indexes on project_id and status.",
  "whatWasLeftUndone": "",
  "verification": {
    "commandsRun": [
      {
        "command": "bun test tests/tasks.test.ts",
        "exitCode": 0,
        "observation": "5 tests passing: creates task, validates required fields, rejects invalid status, prevents duplicates, returns 404 for missing project"
      },
      {
        "command": "bun run typecheck",
        "exitCode": 0,
        "observation": "No type errors"
      },
      {
        "command": "bun run dev & sleep 2 && curl -X POST http://localhost:3200/api/tasks -H 'Content-Type: application/json' -d '{\"agent_id\":\"agent-1\",\"project_id\":\"proj-1\",\"title\":\"Test task\",\"task_type\":\"implementation\"}'",
        "exitCode": 0,
        "observation": "Returns 201 with {id, title, status: 'backlog', created_at, ...}"
      }
    ],
    "interactiveChecks": []
  },
  "tests": {
    "added": [
      {
        "file": "tests/tasks.test.ts",
        "cases": [
          {"name": "creates task with valid data", "verifies": "POST /api/tasks returns 201"},
          {"name": "rejects missing required fields", "verifies": "400 validation"},
          {"name": "rejects invalid status", "verifies": "400 for bad enum"},
          {"name": "prevents duplicate titles in project", "verifies": "409 conflict"},
          {"name": "returns 404 for missing project", "verifies": "Project existence check"}
        ]
      }
    ]
  },
  "discoveredIssues": []
}

When to Return to Orchestrator

• Database migration conflicts with existing schema
• API design conflicts with existing endpoints
• Missing dependencies that cannot be installed
• Unclear requirements about business logic