---
phase: 16-frontend-scaffold
plan: 02
subsystem: infra
tags: [typescript, trpc, monorepo, shared-types]

# Dependency graph
requires:
  - phase: 02-data-layer
    provides: DB entity types (Initiative, Phase, Plan, Task, Agent, Message)
  - phase: 01.1-hexagonal-architecture
    provides: tRPC AppRouter type
provides:
  - "@codewalk-district/shared package exporting AppRouter and entity types"
  - "Type-safe imports for frontend consumers"
affects: [17-initiative-dashboard, 18-initiative-detail, 19-agent-inbox, 16-03-trpc-client]

# Tech tracking
tech-stack:
  added: []
  patterns: ["shared types package for monorepo type sharing via relative re-exports"]

key-files:
  created:
    - packages/shared/package.json
    - packages/shared/tsconfig.json
    - packages/shared/src/index.ts
    - packages/shared/src/trpc.ts
    - packages/shared/src/types.ts
  modified:
    - package-lock.json

key-decisions:
  - "Dropped composite from tsconfig — no build step, consumed directly via TypeScript"
  - "Set rootDir to ../.. so tsc resolves relative imports into backend source without rootDir violations"
  - "Added skipLibCheck to avoid drizzle-orm third-party type errors in gel/mysql modules"

# Metrics
duration: 3min
completed: 2026-02-04
---

# Phase 16 Plan 02: Shared Types Package Summary

**@codewalk-district/shared package exporting AppRouter and entity types via relative re-exports for frontend consumption**

## Performance

- **Duration:** 3 min
- **Started:** 2026-02-04T17:54:00Z
- **Completed:** 2026-02-04T17:57:00Z
- **Tasks:** 1
- **Files modified:** 6

## Accomplishments
- Created packages/shared/ with type-only re-exports for AppRouter and DB entity types
- Frontend can now import types from @codewalk-district/shared instead of reaching into backend internals
- TypeScript compiles cleanly in both shared package and root project
- All 452 existing tests pass with no regressions

## Task Commits

Each task was committed atomically:

1. **Task 1: Create shared types package** - `4a37371` (feat)

## Files Created/Modified
- `packages/shared/package.json` - Package manifest for @codewalk-district/shared
- `packages/shared/tsconfig.json` - TypeScript config with rootDir set to repo root for relative imports
- `packages/shared/src/index.ts` - Barrel export of AppRouter and entity types
- `packages/shared/src/trpc.ts` - Re-exports AppRouter from backend router
- `packages/shared/src/types.ts` - Re-exports Initiative, Phase, Plan, Task, Agent, Message from schema
- `package-lock.json` - Updated with workspace linking

## Decisions Made
- 16-02: Dropped `composite: true` from tsconfig since package has no build step (consumed directly via TypeScript)
- 16-02: Set `rootDir: "../.."` to allow TypeScript to resolve relative imports into backend source without rootDir violations
- 16-02: Added `skipLibCheck: true` to avoid drizzle-orm third-party declaration errors (gel/mysql modules)

## Deviations from Plan

### Auto-fixed Issues

**1. [Rule 3 - Blocking] Fixed TypeScript rootDir and composite configuration**
- **Found during:** Task 1 (TypeScript compilation verification)
- **Issue:** Plan specified `composite: true` but tsc with composite requires all referenced files under rootDir. Relative imports into `../../src/` caused rootDir violations and file-not-in-project errors.
- **Fix:** Removed `composite`, set `rootDir: "../.."`, added `skipLibCheck: true`
- **Files modified:** packages/shared/tsconfig.json
- **Verification:** `npx tsc --noEmit` passes in both shared package and root project
- **Committed in:** 4a37371 (part of task commit)

---

**Total deviations:** 1 auto-fixed (1 blocking)
**Impact on plan:** Auto-fix necessary for TypeScript compilation. No scope creep.

## Issues Encountered
None

## User Setup Required
None - no external service configuration required.

## Next Phase Readiness
- Shared types package ready for tRPC client wiring in Plan 03
- AppRouter type importable from @codewalk-district/shared
- Entity types importable for component props

---
*Phase: 16-frontend-scaffold*
*Completed: 2026-02-04*
