Monorepo Sync Types

monorepo-sync-types — regenerate + propagate backend types across the monorepo

Contract

See references/contracts.md (vendored from dev-flow). Key facts:

• Reads <project-root>/.workflow/meta.json#stack.framework — must be "monorepo".
• Reads meta.json#stack.db and stack.auth to determine the source of truth:
  • "supabase" → run supabase gen types typescript against the linked project.
  • "neon-drizzle" → introspect/pull via drizzle-kit and re-export InferSelectModel/InferInsertModel from the Drizzle schema (this is the default DB for most projects — see module-add/references/module-db.md).
  • "trpc" → re-import the server router type and re-export it.
  • "firebase" → no auto-gen, but normalize fixed types from Firestore rules (limited).
  • "custom-rest" → ask the user where the schema lives (Zod / OpenAPI / TS source).
• Writes generated types into packages/shared/src/types/ (NOT into packages/api/, because packages/shared is consumed by BOTH apps including for non-backend code).
• Idempotent: regenerating overwrites; no-diff prints "already in sync".
• Does NOT modify phase.

When this skill applies

• User says: "rigenera i tipi", "sync DB schema", "supabase types update", "the backend changed, update types".
• Orchestrator does NOT route here automatically — invoked on demand (e.g., after a backend migration).

Knowledge dependencies

• monorepo-bootstrap/references/structure.md — for packages/shared/src/types/ location.
• rn-backend/references/<provider>.md — for provider-specific gen commands.
• module-add/references/module-db.md — for the web side conventions.

Workflow

Step 1 — Verify preconditions

Read .workflow/meta.json. Abort if:

• stack.framework != "monorepo".
• stack.db == null AND stack.auth == null → "No backend configured yet. Run module-add db or rn-module-add db first."

Read meta.json#stack_config.supabase_project_ref (or equivalent) for the gen command target.

Step 2 — Branch by provider

Supabase

Run the canonical gen command:

npx supabase gen types typescript --project-id <ref> > packages/shared/src/types/database.ts

(or --linked if supabase login + supabase link already done.)

Add to packages/shared/src/index.ts:

export type { Database } from './types/database';

Add a typed Supabase client wrapper in packages/api/src/client.ts:

import { createClient } from '@supabase/supabase-js';
import type { Database } from '@<slug>/shared/types/database';

export const supabase = createClient<Database>(
  process.env.EXPO_PUBLIC_SUPABASE_URL!, // or NEXT_PUBLIC_ on web side — see decision-tree
  process.env.EXPO_PUBLIC_SUPABASE_ANON_KEY!,
);

Both web and mobile apps now import supabase from @<slug>/api/client and get full type safety: supabase.from('posts').select(...) is fully typed.

neon-drizzle

This is the default DB stack for most projects (see module-add/references/module-db.md). Drizzle's schema file is already the source of truth for types — there's no separate "gen types" command — so syncing means two things: (1) make sure the schema file matches the live DB, and (2) re-export row types to packages/shared/.

1. If drift with the live database is suspected (someone ran DDL outside Drizzle, or this is the first sync), refresh the schema from the database:

   npx drizzle-kit pull
   

   This introspects the Neon database and (re)writes the schema file. Confirm the target path against module-add/references/module-db.md — by default apps/web/lib/db/schema.ts.
2. Re-export typed rows via InferSelectModel / InferInsertModel (from drizzle-orm) into packages/shared/src/types/db.ts:

   import type { InferSelectModel, InferInsertModel } from 'drizzle-orm';
   import { users, posts } from '../../../../apps/web/lib/db/schema'; // adjust relative path to the real schema location
   
   export type User = InferSelectModel<typeof users>;
   export type NewUser = InferInsertModel<typeof users>;
   export type Post = InferSelectModel<typeof posts>;
   export type NewPost = InferInsertModel<typeof posts>;
   

3. Add to packages/shared/src/index.ts:

   export * from './types/db';
   

If the schema file was hand-edited to add tables/columns that haven't reached the database yet, don't pull (it would overwrite the new columns) — instead run the migration first (drizzle-kit generate + drizzle-kit migrate; drizzle-kit push is dev-only and destructive on column drops, per module-add/references/module-db.md), then re-export types from the now-current schema.

tRPC

The types flow automatically via TS inference — no gen step. The skill verifies the wiring is correct:

1. packages/api/src/client.ts imports the server's AppRouter type:

   import type { AppRouter } from '../../../server/src/router';
   export const trpc = createTRPCReact<AppRouter>();
   

2. (Optional) Re-export Zod-derived input/output types from packages/shared/src/types/:

   import type { inferRouterOutputs } from '@trpc/server';
   import type { AppRouter } from '../../api/src/router-type'; // a re-export
   export type RouterOutputs = inferRouterOutputs<AppRouter>;
   

If the server lives outside the monorepo: import via a published @<scope>/types package OR copy the router types file into packages/shared/src/types/router.d.ts and tell the user to keep it in sync.

Firebase

No auto-gen. The skill creates skeleton types from Firestore rules + user input:

1. Ask the user for the collections in use (or parse firestore.rules).
2. For each collection, ask the user for the document shape OR generate a placeholder.
3. Write packages/shared/src/types/firestore.ts with the shapes.

This is a manual-maintenance scenario — Firebase doesn't ship a type-gen tool the way Supabase does.

Custom REST

Ask the user where the schema lives:

• Zod schemas in the server: ask for the path, generate packages/shared/src/types/api.ts via z.infer<typeof Schema> for each.
• OpenAPI spec: ask for the YAML/JSON path, run npx openapi-typescript <spec> -o packages/shared/src/types/api.d.ts.
• TS source in a separate repo: copy the relevant types into packages/shared/src/types/api.ts and instruct the user to keep in sync.

Step 3 — Verify

Run pnpm tsc --noEmit from apps/web, apps/mobile, and packages/shared. Must pass.

If types changed in ways that broke existing code, report each error — the user fixes the consumers (the skill doesn't auto-fix arbitrary call sites).

Step 4 — Update meta.json + commit

{
  "stack_config": {
    "types_last_synced_at": "<iso>",
    "types_source": "supabase" // or "neon-drizzle" / "trpc" / "firebase" / "custom-rest"
  },
  "history": [
    ...,
    { "skill": "monorepo-sync-types", "ran_at": "<iso>", "outputs": [...] }
  ]
}

If git repo: commit with chore(types): sync from <provider>.

Common anti-patterns (NEVER do)

• ❌ Generate types into packages/api/ — types are general-purpose, both apps consume them; they live in packages/shared/.
• ❌ Hand-edit generated type files — they will be overwritten next sync.
• ❌ Skip the packages/shared/src/index.ts re-export — apps would need deep import paths.
• ❌ Forget the --project-id flag on supabase gen types — it will fail or generate the wrong schema.
• ❌ Run gen without verifying the user is logged into the right project (supabase status).
• ❌ For tRPC: import the server router via a brittle relative path (../../../../server/src/router). Instead use a workspace import if the server is in the monorepo, or a .d.ts shim file if not.

Updating meta.json (recommended pattern)

python3 .../dev-flow/scripts/update_meta.py <project-root> record-artifact \
    --path packages/shared/src/types/database.ts --produced-by 'monorepo-sync-types'
python3 .../dev-flow/scripts/update_meta.py <project-root> append-history \
    --skill 'monorepo-sync-types' --inputs '{"source": "supabase"}' --outputs '{"types": "packages/shared/src/types/database.ts"}'

Sources

• Spec: docs/superpowers/specs/2026-05-29-monorepo-set-design.md
• Official: https://supabase.com/docs/guides/api/rest/generating-types
• Official: https://trpc.io/docs/quickstart#using-trpcs-types-on-the-client
• monorepo-bootstrap/references/structure.md