ADR: Prisma Schema Consolidation

Status: Accepted Date: 2026-01-12 Deciders: Architecture Team Related: Prisma 7 Migration

Context

Current State

The monorepo has two separate Prisma setups:

Location	Package	Version	Output
packages/database	@emergexyz/db	6.16.3	Default (node_modules/.prisma/client)
apps/miniapp	Local	6.13.0/6.15.0	lib/generated/prisma

Problems

1. Schema Drift: Two schemas that should be identical can diverge
2. Migration Conflicts: Two migration histories for the same database
3. Duplicate Dependencies: Prisma installed twice in the monorepo
4. Inconsistent Versions: miniapp on 6.13, packages/database on 6.16
5. Maintenance Burden: Schema changes must be made in two places

Schema Comparison

Both schemas share the same models (api_key, assignment, chat, etc.) but differ in:

# packages/database
generator client {
  provider      = "prisma-client-js"
  binaryTargets = ["native", "rhel-openssl-3.0.x"]  # For deployment
}

# apps/miniapp
generator client {
  provider = "prisma-client-js"
  output   = "../lib/generated/prisma"  # Custom output path
}

Decision

Consolidate all Prisma usage to packages/database (@emergexyz/db).

Changes Required

1. Remove miniapp's local Prisma:

   • Delete apps/miniapp/prisma/ directory
   • Remove prisma and @prisma/client from miniapp's dependencies
   • Remove postinstall: prisma generate script

2. Add dependency on shared package:

   {
     "dependencies": {
       "@emergexyz/db": "workspace:*"
     }
   }

3. Update imports:

   // Before
   import { PrismaClient } from "@/lib/generated/prisma";
   
   // After
   import { prisma } from "@emergexyz/db";
   // Or for types:
   import type { User, Output } from "@emergexyz/db";

4. Update packages/database exports (if needed):

   • Ensure all types are exported
   • Add any miniapp-specific models to shared schema

Implementation

Phase 1: Schema Sync Verification

1. Diff the two schemas to identify any differences
2. Merge any miniapp-only models into packages/database
3. Run migration if schema changes needed

Phase 2: Miniapp Migration

1. Add @emergexyz/db dependency to miniapp
2. Update all Prisma imports (find/replace)
3. Update lib/prisma.ts to re-export from shared package
4. Remove local Prisma setup

Phase 3: Cleanup

1. Delete apps/miniapp/prisma/ directory
2. Delete apps/miniapp/lib/generated/ directory
3. Remove Prisma dev dependencies from miniapp
4. Verify build succeeds

Consequences

Positive

• Single Source of Truth: One schema, one migration history
• Consistent Types: All apps use same generated types
• Easier Maintenance: Schema changes in one place
• Smaller Bundle: No duplicate Prisma client in miniapp
• Version Consistency: All consumers on same Prisma version

Negative

• Migration Effort: Need to update all imports in miniapp
• Build Dependency: miniapp build depends on packages/database being built first

Neutral

• Turbo Pipeline: Already handles package dependencies correctly

Files Affected

apps/miniapp/
├── package.json           # Remove prisma deps, add @emergexyz/db
├── lib/prisma.ts         # Update to use shared package
├── lib/generated/        # DELETE entirely
├── prisma/               # DELETE entirely
└── **/*.ts               # Update imports

packages/database/
├── prisma/schema.prisma  # May need new models from miniapp
└── src/index.ts          # Ensure all types exported

Rollback Plan

If issues arise:

1. Restore miniapp's prisma/ directory from git
2. Revert package.json changes
3. Run prisma generate in miniapp

References

• Prisma in Monorepos
• pnpm Workspaces