turborepo-caching

$npx skills add wshobson/agents --skill turborepo-caching
SKILL.md

Turborepo Caching

Production patterns for Turborepo build optimization. - Setting up new Turborepo projects - Configuring build pipelines

Turborepo Caching

Production patterns for Turborepo build optimization.

When to Use This Skill

  • Setting up new Turborepo projects
  • Configuring build pipelines
  • Implementing remote caching
  • Optimizing CI/CD performance
  • Migrating from other monorepo tools
  • Debugging cache misses

Core Concepts

1. Turborepo Architecture

Workspace Root/
├── apps/
│   ├── web/
│   │   └── package.json
│   └── docs/
│       └── package.json
├── packages/
│   ├── ui/
│   │   └── package.json
│   └── config/
│       └── package.json
├── turbo.json
└── package.json

2. Pipeline Concepts

Concept
Description
dependsOn
Tasks that must complete first
cache
Whether to cache outputs
outputs
Files to cache
inputs
Files that affect cache key
persistent
Long-running tasks (dev servers)

Templates

Template 1: turbo.json Configuration

{
  "$schema": "https://turbo.build/schema.json",
  "globalDependencies": [".env", ".env.local"],
  "globalEnv": ["NODE_ENV", "VERCEL_URL"],
  "pipeline": {
    "build": {
      "dependsOn": ["^build"],
      "outputs": ["dist/**", ".next/**", "!.next/cache/**"],
      "env": ["API_URL", "NEXT_PUBLIC_*"]
    },
    "test": {
      "dependsOn": ["build"],
      "outputs": ["coverage/**"],
      "inputs": ["src/**/*.tsx", "src/**/*.ts", "test/**/*.ts"]
    },
    "lint": {
      "outputs": [],
      "cache": true
    },
    "typecheck": {
      "dependsOn": ["^build"],
      "outputs": []
    },
    "dev": {
      "cache": false,
      "persistent": true
    },
    "clean": {
      "cache": false
    }
  }
}
`### Template 2: Package-Specific Pipeline`
// apps/web/turbo.json
{
  "$schema": "https://turbo.build/schema.json",
  "extends": ["//"],
  "pipeline": {
    "build": {
      "outputs": [".next/**", "!.next/cache/**"],
      "env": ["NEXT_PUBLIC_API_URL", "NEXT_PUBLIC_ANALYTICS_ID"]
    },
    "test": {
      "outputs": ["coverage/**"],
      "inputs": ["src/**", "tests/**", "jest.config.js"]
    }
  }
}
`### Template 3: Remote Caching with Vercel`
# Login to Vercel
npx turbo login

# Link to Vercel project
npx turbo link

# Run with remote cache
turbo build --remote-only

# CI environment variables
TURBO_TOKEN=your-token
TURBO_TEAM=your-team
# .github/workflows/ci.yml
name: CI

on:
  push:
    branches: [main]
  pull_request:

env:
  TURBO_TOKEN: ${{ secrets.TURBO_TOKEN }}
  TURBO_TEAM: ${{ vars.TURBO_TEAM }}

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - uses: actions/setup-node@v4
        with:
          node-version: 20
          cache: "npm"

      - name: Install dependencies
        run: npm ci

      - name: Build
        run: npx turbo build --filter='...[origin/main]'

      - name: Test
        run: npx turbo test --filter='...[origin/main]'
`### Template 4: Self-Hosted Remote Cache`
// Custom remote cache server (Express)
import express from "express";
import { createReadStream, createWriteStream } from "fs";
import { mkdir } from "fs/promises";
import { join } from "path";

const app = express();
const CACHE_DIR = "./cache";

// Get artifact
app.get("/v8/artifacts/:hash", async (req, res) => {
  const { hash } = req.params;
  const team = req.query.teamId || "default";
  const filePath = join(CACHE_DIR, team, hash);

  try {
    const stream = createReadStream(filePath);
    stream.pipe(res);
  } catch {
    res.status(404).send("Not found");
  }
});

// Put artifact
app.put("/v8/artifacts/:hash", async (req, res) => {
  const { hash } = req.params;
  const team = req.query.teamId || "default";
  const dir = join(CACHE_DIR, team);
  const filePath = join(dir, hash);

  await mkdir(dir, { recursive: true });

  const stream = createWriteStream(filePath);
  req.pipe(stream);

  stream.on("finish", () => {
    res.json({
      urls: [`${req.protocol}://${req.get("host")}/v8/artifacts/${hash}`],
    });
  });
});

// Check artifact exists
app.head("/v8/artifacts/:hash", async (req, res) => {
  const { hash } = req.params;
  const team = req.query.teamId || "default";
  const filePath = join(CACHE_DIR, team, hash);

  try {
    await fs.access(filePath);
    res.status(200).end();
  } catch {
    res.status(404).end();
  }
});

app.listen(3000);
// turbo.json for self-hosted cache
{
  "remoteCache": {
    "signature": false
  }
}
# Use self-hosted cache
turbo build --api="http://localhost:3000" --token="my-token" --team="my-team"
`### Template 5: Filtering and Scoping`
# Build specific package
turbo build --filter=@myorg/web

# Build package and its dependencies
turbo build --filter=@myorg/web...

# Build package and its dependents
turbo build --filter=...@myorg/ui

# Build changed packages since main
turbo build --filter='...[origin/main]'

# Build packages in directory
turbo build --filter='./apps/*'

# Combine filters
turbo build --filter=@myorg/web --filter=@myorg/docs

# Exclude package
turbo build --filter='!@myorg/docs'

# Include dependencies of changed
turbo build --filter='...[HEAD^1]...'
`### Template 6: Advanced Pipeline Configuration`
{
  "$schema": "https://turbo.build/schema.json",
  "pipeline": {
    "build": {
      "dependsOn": ["^build"],
      "outputs": ["dist/**"],
      "inputs": ["$TURBO_DEFAULT
quot;, "!**/*.md", "!**/*.test.*"] }, "test": { "dependsOn": ["^build"], "outputs": ["coverage/**"], "inputs": ["src/**", "tests/**", "*.config.*"], "env": ["CI", "NODE_ENV"] }, "test:e2e": { "dependsOn": ["build"], "outputs": [], "cache": false }, "deploy": { "dependsOn": ["build", "test", "lint"], "outputs": [], "cache": false }, "db:generate": { "cache": false }, "db:push": { "cache": false, "dependsOn": ["db:generate"] }, "@myorg/web#build": { "dependsOn": ["^build", "@myorg/db#db:generate"], "outputs": [".next/**"], "env": ["NEXT_PUBLIC_*"] } } } `### Template 7: Root package.json Setup` { "name": "my-turborepo", "private": true, "workspaces": ["apps/*", "packages/*"], "scripts": { "build": "turbo build", "dev": "turbo dev", "lint": "turbo lint", "test": "turbo test", "clean": "turbo clean && rm -rf node_modules", "format": "prettier --write \"**/*.{ts,tsx,md}\"", "changeset": "changeset", "version-packages": "changeset version", "release": "turbo build --filter=./packages/* && changeset publish" }, "devDependencies": { "turbo": "^1.10.0", "prettier": "^3.0.0", "@changesets/cli": "^2.26.0" }, "packageManager": "npm@10.0.0" } `## Debugging Cache` # Dry run to see what would run turbo build --dry-run # Verbose output with hashes turbo build --verbosity=2 # Show task graph turbo build --graph # Force no cache turbo build --force # Show cache status turbo build --summarize # Debug specific task TURBO_LOG_VERBOSITY=debug turbo build --filter=@myorg/web

Best Practices

Do's

  • Define explicit inputs - Avoid cache invalidation
  • Use workspace protocol - "@myorg/ui": "workspace:*"
  • Enable remote caching - Share across CI and local
  • Filter in CI - Build only affected packages
  • Cache build outputs - Not source files

Don'ts

  • Don't cache dev servers - Use persistent: true
  • Don't include secrets in env - Use runtime env vars
  • Don't ignore dependsOn - Causes race conditions
  • Don't over-filter - May miss dependencies

Resources