TypeScript Monorepo Builds

Quick Reference

# Build all packages (respects dependency order)
pnpm turbo build

# Build specific package and its dependencies
pnpm --filter @orientbot/package-name... build

# Type check without building
pnpm turbo typecheck

# Clean all build artifacts
pnpm turbo clean

Package tsconfig.json Template

Every package in packages/ should have this configuration:

{
  "compilerOptions": {
    "target": "ES2022",
    "module": "NodeNext",
    "moduleResolution": "NodeNext",
    "lib": ["ES2022"],
    "outDir": "./dist",
    "rootDir": "./src",
    "declaration": true,
    "declarationMap": true,
    "sourceMap": true,
    "strict": true,
    "esModuleInterop": true,
    "skipLibCheck": true,
    "forceConsistentCasingInFileNames": true,
    "resolveJsonModule": true,
    "isolatedModules": true
  },
  "include": ["src/**/*.ts"],
  "exclude": ["node_modules", "dist", "__tests__"]
}

Key Options Explained

Project References (For Cross-Package Imports)

When a package imports from another package at compile time, add project references:

{
  "compilerOptions": {
    "composite": true
  },
  "references": [{ "path": "../core" }, { "path": "../database" }]
}

Note: Project references require composite: true in the referenced package's tsconfig.

When to Use References

• ✅ Package directly imports types from another package
• ✅ Package uses workspace dependency ("@orientbot/core": "workspace:*")
• ❌ Package only uses runtime exports (no compile-time dependency)

Build Order with Turbo

Turbo automatically builds dependencies first via dependsOn: ["^build"]:

// turbo.json
{
  "tasks": {
    "build": {
      "dependsOn": ["^build"],
      "outputs": ["dist/**"]
    }
  }
}

Build Order

1. @orientbot/core (no dependencies)
2. @orientbot/database (depends on core)
3. @orientbot/database-services (depends on database)
4. @orientbot/integrations (depends on core, database)
5. @orientbot/agents (depends on database-services)
6. @orientbot/mcp-tools (depends on agents, integrations)
7. @orientbot/bot-* (depends on mcp-tools, agents)

Root tsconfig.json Path Aliases

The root tsconfig.json defines path aliases for development:

{
  "compilerOptions": {
    "baseUrl": ".",
    "paths": {
      "@orientbot/core": ["./packages/core/src/index"],
      "@orientbot/database": ["./packages/database/src/index"],
      "@orientbot/agents": ["./packages/agents/src/index"]
    }
  }
}

Important: Path aliases point to source files for development, but production builds use dist via package.json exports.

Incremental Compilation Troubleshooting

Stale .tsbuildinfo Files

Symptom: Build completes with no errors but dist/ is empty. Turbo shows "cache hit" or warns "no output files found."

Cause: .tsbuildinfo stores incremental state. When stale, tsc skips compilation entirely.

Fix:

find packages -name "*.tsbuildinfo" -delete
rm -f .tsbuildinfo
pnpm run build:packages

Verifying Build Completion

Always verify dist/ before running dependent builds or tests:

# After build, verify all packages have dist/index.js
ls packages/*/dist/index.js

# If any are missing, that package didn't compile
# Check for stale tsbuildinfo or stray .js files in src/

Empty dist/ Despite "Cache Hit"

Turbo's cache can be misleading when tsbuildinfo is stale:

1. Turbo checks its cache → finds cached task
2. Replays cached tsc (which produced no output due to stale tsbuildinfo)
3. Result: "cache hit" but empty dist/

Fix: Clean both turbo cache AND tsbuildinfo:

rm -rf .turbo packages/*/.turbo
find packages -name "*.tsbuildinfo" -delete
pnpm run build:packages

Common Build Errors

"Cannot find module '@orientbot/package'" (TS2307)

Most common cause: Prerequisite package didn't build (empty dist/).

1. Verify prerequisite dist exists: ls packages/package/dist/index.js
2. If empty, clean tsbuildinfo and rebuild: find packages -name "*.tsbuildinfo" -delete && pnpm run build:packages
3. If still failing, check package.json exports match dist structure

"Type 'X' is not assignable to type 'Y'"

Cross-package type mismatches usually mean:

1. Stale build: Run pnpm turbo build --force
2. Different TypeScript versions: Check peerDependencies
3. Missing type export: Add to package's index.ts

"Cannot find name 'X'" in tests

Tests don't use project references. Add vitest path aliases:

// vitest.config.ts
export default defineConfig({
  resolve: {
    alias: {
      '@orientbot/core': resolve(__dirname, '../core/src'),
    },
  },
});

"Declaration emit skipped"

error TS5069: Option 'declarationDir' cannot be specified

Ensure outDir is set and remove declarationDir:

{
  "compilerOptions": {
    "outDir": "./dist",
    "declaration": true
  }
}

Circular Reference Error

error TS6202: Project references may not form a circular graph

Check references in tsconfig files. Package A cannot reference B if B references A.

Creating a New Package

1. Create package structure:

   bashCopy

   mkdir -p packages/new-package/src
   

2. Create package.json:

   jsonCopy

   {
     "name": "@orientbot/new-package",
     "version": "1.0.0",
     "type": "module",
     "main": "./dist/index.js",
     "types": "./dist/index.d.ts",
     "exports": {
       ".": {
         "types": "./dist/index.d.ts",
         "import": "./dist/index.js"
       }
     },
     "scripts": {
       "build": "tsc",
       "typecheck": "tsc --noEmit"
     }
   }
   

3. Create tsconfig.json using the template above

4. Add workspace dependency to consumers:

   jsonCopy

   {
     "dependencies": {
       "@orientbot/new-package": "workspace:*"
     }
   }
   

5. Add path alias to root tsconfig.json

6. Build: pnpm --filter @orientbot/new-package build

Debugging Build Issues

# Verbose TypeScript output
pnpm --filter @orientbot/package tsc --listFiles

# Check what files are included
pnpm --filter @orientbot/package tsc --listFilesOnly

# Trace module resolution
pnpm --filter @orientbot/package tsc --traceResolution

# Show build dependency graph
pnpm turbo build --graph

# Force rebuild ignoring cache
pnpm turbo build --force

Best Practices

1. Keep packages focused - smaller packages = faster builds
2. Use composite: true only when needed for references
3. Build before testing - dependsOn: ["^build"] in turbo.json
4. Export types explicitly - export type { X } in barrel files
5. Match exports to dist - package.json exports must match dist structure