Monorepos with TypeScript: Nx, Turborepo Basics

Table of Contents

• What is a Monorepo?
• Benefits of Monorepos
• Overview of Nx and Turborepo
  • What is Nx?
  • What is Turborepo?
• Setting Up a Monorepo with Nx
• Setting Up a Monorepo with Turborepo
• Comparison of Nx vs. Turborepo
• Best Practices for Managing a TypeScript Monorepo
• Conclusion

What is a Monorepo?

A monorepo (short for “monolithic repository”) is a version-controlled code repository that holds multiple projects or applications in the same repository. These projects can share common dependencies, configuration files, and libraries. Unlike traditional approaches where each project has its own repository, monorepos centralize code and make it easier to manage multiple related projects.

Benefits of Monorepos

• Centralized Management: All projects are maintained in a single codebase, which makes dependency management and version control more streamlined.
• Shared Code: Common libraries, utilities, and configuration files can be shared across projects without duplication.
• Consistent CI/CD: Monorepos help you standardize and unify the build and test processes across projects, reducing overhead in maintaining multiple CI/CD pipelines.
• Atomic Changes: Monorepos allow you to make atomic changes that span multiple projects, ensuring consistency when upgrading dependencies or applying refactors.

Overview of Nx and Turborepo

Both Nx and Turborepo are modern tools designed to help developers manage monorepos, providing powerful features such as dependency graph visualization, optimized builds, and caching mechanisms. Let’s dive into what these tools are and how they can help with TypeScript-based monorepo setups.

What is Nx?

Nx is an open-source set of extensible dev tools built for managing monorepos. It was developed by the team at Nrwl and provides a set of tools to streamline the development process for large applications and libraries within a monorepo.

Nx offers a rich ecosystem with capabilities such as:

• Powerful CLI: A command-line interface for generating, building, testing, and managing projects in a monorepo.
• Project Graph: A visualization of the dependencies between your projects, which helps optimize builds and test strategies.
• Computation Caching: Nx caches build outputs and tests to avoid redundant computations, speeding up build times.
• Integration with Popular Frameworks: Nx has integrations for React, Angular, Node.js, NestJS, and more, making it easy to set up and manage projects in your monorepo.

What is Turborepo?

Turborepo is another open-source tool designed to optimize the management of monorepos, focusing on speed and developer experience. It was created by Vercel and is known for its emphasis on build caching and parallel execution to significantly reduce build times.

Key features of Turborepo include:

• Parallel Task Execution: Turborepo allows tasks like building and testing to run in parallel, leveraging multiple CPU cores.
• Incremental Builds: By caching build outputs and reusing them when possible, Turborepo accelerates rebuilds and deployments.
• Task Pipelines: Turborepo helps organize tasks in pipelines, enabling fine-grained control over the order and dependencies of tasks in your monorepo.

Setting Up a Monorepo with Nx

Nx is a feature-rich tool that integrates various types of projects into a monorepo structure. Here’s how you can set up an Nx-based monorepo with TypeScript.

Step 1: Install Nx

To set up Nx, you’ll need to install the Nx CLI globally.

npm install -g nx

Step 2: Create an Nx Workspace

You can create an Nx workspace using the following command. You will be prompted to choose the type of workspace (e.g., React, Node, etc.).

npx create-nx-workspace@latest my-monorepo

This will generate a new workspace with a structure where you can start adding projects like apps or libraries.

Step 3: Add TypeScript Projects to the Workspace

To add a TypeScript project (e.g., a Node.js app or a React app), use the nx generate command.

nx generate @nrwl/node:application my-app

This will create a new TypeScript-based application in the apps/ directory.

You can also create libraries that can be shared between apps:

nx generate @nrwl/node:library my-lib

This will generate a shared library in the libs/ directory.

Step 4: Manage Dependencies and Build Configurations

Nx allows you to manage dependencies and build configurations between apps and libraries. For example, if my-app depends on my-lib, you can visualize this dependency in the project graph, and Nx will optimize the build process.

To visualize the project graph:

nx dep-graph

Setting Up a Monorepo with Turborepo

Turborepo focuses on fast builds, parallel task execution, and caching. Here’s how you can set up a Turborepo-based monorepo for TypeScript.

Step 1: Install Turborepo

First, install Turborepo globally via npm:

npm install -g turbo

Alternatively, you can use npx to run it without installing globally.

Step 2: Create a New Project

You can create a new Turborepo project by following the official documentation, which provides a starter template for TypeScript.

npx create-turbo@latest my-monorepo

This will generate a new Turborepo workspace with sample apps and libraries.

Step 3: Set Up TypeScript Projects

Inside the monorepo, you can set up multiple TypeScript-based applications and libraries. For example, you can create a new app in the apps/ directory and a shared library in the libs/ directory.

You can manage build pipelines and tasks for each of your projects in the turbo.json file.

{
  "pipeline": {
    "build": {
      "dependsOn": ["^build"],
      "outputs": ["dist/**"]
    },
    "test": {
      "dependsOn": ["build"]
    }
  }
}

This file specifies how tasks are dependent on each other and how caching is handled.

Step 4: Running Tasks in Parallel

Turborepo automatically runs tasks in parallel, so tasks like building and testing can be executed faster. For example:

turbo run build

This will build all projects in the monorepo, utilizing caching and parallel execution to speed up the process.

Comparison of Nx vs. Turborepo

Best Practices for Managing a TypeScript Monorepo

1. Modularize your Code: Split your codebase into smaller, reusable libraries (e.g., utilities, components) to promote reuse across different applications within the monorepo.
2. Use Workspaces: If your project dependencies need to be shared between multiple apps, configure TypeScript workspaces for smooth dependency management.
3. Leverage Caching: Both Nx and Turborepo offer caching mechanisms to improve build performance. Take full advantage of these to speed up your development cycle.
4. Set Up Continuous Integration: Ensure that your CI/CD pipelines are optimized for monorepo workflows. Use tools that can understand the dependencies between your apps and libraries.
5. Type Checking Across Projects: Use a shared tsconfig.json and paths to ensure consistent TypeScript settings across all applications and libraries.

Conclusion

Monorepos with TypeScript can be a highly efficient way to manage large-scale projects. Nx and Turborepo are powerful tools that help streamline workflows, optimize builds, and enable parallel task execution. Whether you prioritize feature richness (Nx) or blazing-fast builds (Turborepo), both tools offer excellent solutions for TypeScript-based monorepo management. By following best practices and leveraging these tools, you can create a scalable and efficient development environment for your teams.