Nx — Smart Monorepos and Fast CI for JavaScript and Beyond

Introduction

Nx (by Nrwl, now Nx) brings Google-scale monorepo techniques to everyday projects. It understands your project graph, caches every task, and runs only what changed. The same command that takes 20 minutes without Nx can finish in seconds on a warm cache.

With over 29,000 GitHub stars, Nx is used by Cisco, Capital One, Walmart, and any team that feels the pain of slow monorepo CI. It supports Angular, React, Next.js, Vue, Node, NestJS, Express, Go, Rust, Python, Java, and more via plugins.

What Nx Does

Nx analyzes your project (via nx.json + project.json files) to build a dependency graph. Every task (build, test, lint, e2e) is cached by inputs — source files, environment, deps. Cache hits are reused locally or shared via Nx Cloud. nx affected runs tasks only on projects touched by the current PR.

Architecture Overview

monorepo/
  apps/web, apps/api, libs/ui, libs/auth, libs/utils
        |
   [Project Graph]  derived from imports + project.json
        |
   [Task Graph]     which tasks depend on which
        |
   [Execution]
   +-- Local cache (.nx/cache)
   +-- Remote cache (Nx Cloud / self-hosted)
   +-- Distributed (split tasks across agents)
        |
   [Affected]  git diff --> only touched projects

Self-Hosting & Configuration

// nx.json
{
  "targetDefaults": {
    "build": { "cache": true, "dependsOn": ["^build"], "inputs": ["production", "^production"] },
    "test":  { "cache": true, "inputs": ["default", "^production"] },
    "lint":  { "cache": true }
  },
  "namedInputs": {
    "default":    ["{projectRoot}/**/*"],
    "production": ["default", "!{projectRoot}/**/*.spec.ts"]
  },
  "tasksRunnerOptions": {
    "default": { "runner": "nx/tasks-runners/default",
      "options": { "cacheableOperations": ["build", "test", "lint"] } }
  }
}

npx nx graph                   # interactive project graph
npx nx affected -t test --parallel=4
npx nx reset                   # clear cache
npx nx generate @nx/react:lib ui-components

Key Features

• Computation caching — skip unchanged work, local + remote
• Affected commands — run tasks only on changed projects
• Project graph — visualize dependencies, detect cycles
• Code generators — scaffold apps, libs, components in one command
• Remote cache (Nx Cloud) — share hits across developers and CI
• Distributed task execution — split tests/builds across many agents
• Polyglot — JS/TS first-class; plugins for Go, Python, Rust, Java
• Migrations — automated codemods when upgrading tools/versions

Comparison with Similar Tools

FAQ

Q: Nx vs Turborepo — which should I use? A: Turborepo is simpler and stays out of your way. Nx offers more (generators, plugins, richer graph, affected logic across languages) at the cost of more concepts. For large teams with custom build logic, Nx wins; for small JS monorepos, Turborepo is often enough.

Q: Do I need Nx Cloud? A: Optional. Without it you still get local cache and affected commands. Nx Cloud adds remote cache sharing and DTE (distributed task execution) — huge for CI speed.

Q: Can I adopt Nx in an existing repo? A: Yes. npx nx init adds Nx to any existing workspace without restructuring. You opt in per package.

Q: Does Nx work with pnpm? A: Yes. Nx supports npm, yarn, pnpm, and bun. Pick whichever package manager fits your team.

Sources

• GitHub: https://github.com/nrwl/nx
• Docs: https://nx.dev
• Company: Nx (formerly Nrwl)
• License: MIT