10 Best JavaScript Build Tools and Bundlers Compared

📚 Table of contents:

What is a JavaScript build tool?

Some of you might be new to the concept of incorporating a build process into your websites or apps. So before getting to the tools themselves, let’s briefly look at what a build tool does and why it’s beneficial.

A JavaScript build tool 🧰 provides automation for what we might consider “grunt work” in the process of development. A build tool will automatically perform specific tasks that we would otherwise do manually. Tasks common to almost all build tools are:

• Minifying and/or compressing files
• Optimizing images and/or fonts
• Concatenating files
• Compiling or transpiling code
• Generating a development server
• Hot reloading modules without a full page refresh
• Watching files and generating builds automatically when detecting changes

👉 Tasks performed by build tools that aren’t as common might include:

• Managing and updating dependencies
• Linting code
• Deploying code
• Running unit tests
• Generating documentation
• Polyfilling

Ultimately, the features for any build tool depend on the tool itself and its plugin ecosystem. This article isn’t going to include a feature-by-feature comparison. Instead I’ll focus on features that are unique or outstanding for any particular tool.

Webpack

Webpack is probably the most well-known, commonly referred to as a module bundler. This is because it’s mainly concerned with bundling separate JavaScript modules in the process of a build. Webpack had a fairly steep learning curve during its early stages of development. Recent versions of the tool, however, allow developers to get up and running a lot quicker.

🎯 Some of Webpack’s unique and outstanding features include:

• Advanced Code splitting: Webpack is well-known for enabling you to load specific scripts on demand, rather than pushing out a full bundle on each page.
• Plugins and loaders: Webpack includes a large ecosystem of plugins and loaders to extend its functionality.
• Highly configurable: You can use Webpack without any configuration, but it’s more powerful when it’s configured for each project.
• Support for output formats: Webpack supports a number of different output formats for just about any use case.

Webpack has a steep learning curve and large configuration overhead, so it may be tricky for beginners to do more than the basics with it. It would also likely be overkill to use Webpack for a small project. But for something larger, once you get set up with it, it’s not too difficult to use. And if you run into problems, there’s lots of info online to overcome roadblocks.

If you want a thorough discussion, be sure to check out my full Webpack tutorial.

Parcel

Parcel is another popular build tool written in Rust. Parcel’s main selling point that attracts many developers is the fact that it’s a zero-configuration build tool. Many view Parcel as the anti-Webpack bundler due to Parcel’s ease of use (though Webpack has improved in recent versions).

🎯 Some of Parcel’s unique or outstanding features include:

• Zero config: As alluded to, you don’t need to configure anything to use Parcel, which is something that’s attracted a lot of developers, including those not experienced with build tools.
• Dev-friendly Diagnostics: For errors, Parcel displays beautiful diagnostics in your terminal and in the browser, with syntax highlighting and documentation links.
• Fast Builds: Parcel boasts lightning-fast build times that exceed the speeds of many other build tools.
• Support for different files types: There’s no need to configure Parcel for use with specific file types. Its no-config features have support for just about any frontend project.

Drawbacks to using Parcel would include its limited configurability compared to other solutions. It also has less community and plugin support.

If you’d like a more thorough discussion of using Parcel and its features, be sure to check out my Parcel.js tutorial.

esbuild

esbuild has been produced as an answer to some of the larger and more complex JavaScript build tools, promoted as a bundler that’s faster and easier to use.

🎯 Some of its outstanding features include:

• Speed: It’s built with the Go programming language and claims to be one of the fastest build tools available with build times up to 20x faster than other tools.
• Easy to use: Like Parcel, esbuild doesn’t require any configuration, making it easy to start working with it.
• Tree shaking: esbuild includes support for tree shaking, or removing unused code for smaller bundles.
• Support for JSX and TypeScript: esbuild has built-in support for JSX and TypeScript without the need to install extra plugins or loaders.
• Platform agnostic: Because Go is the language powering esbuild, it can run on any platform that supports Go (including Mac, Windows, and Linux) without the need to install a runtime like Node.js.

Some of the drawbacks to using esbuild might include a smaller plugin ecosystem, fewer configuration options, and lack of customizability. However, esbuild is relatively new so you can expect it to grow and improve in coming years.

Vite

Vite is a JavaScript build tool that’s closely associated with Vue.js, the popular React alternative. It was originally built for Vue.js projects, and the same team that created Vue also built Vite. You can use it in most frontend projects via built-in support for React, Preact, Svelte, and Lit.

🎯 Vite is unique in the build tools space for the following reasons:

• Rollup and esbuild dependency: Vite uses Rollup and esbuild under the hood; esbuild is used for pre-bundling while Rollup is used for Vite’s production builds.
• Vite improves on slow servers: Traditionally, bundler-based build tools take time before serving your application. Vite improves on this by pre-bundling (using esbuild) and serving code using native ES modules.
• HMR using native ES modules: Vite boasts incredibly fast hot module replacement even for large apps (something other solutions have trouble with).

Overall, Vite is a popular project that’s well-maintained and has good documentation.

Drawbacks to using Vite might include a steeper learning curve, smaller plugin ecosystem, and less community support.

Rollup

Rollup is a build tool that’s been around for about 8 years and is relatively popular with continued maintenance and updates.

🎯 It’s a module bundler that includes features such as:

• Tree-shaking: Rollup is especially revered for its tree shaking (removing unused code) that ensures the smallest bundle sizes.
• Output formats: Rollup is a mature option that has support for different output formats including CommonJS, AMD, UMD, and native ES modules for modern projects.
• Non-opinionated config: Unlike a tool like Parcel, Rollup is designed for configuration and extensibility, allowing developers to customize it as needed.

Rollup’s website includes a REPL that allows you to try out different module formats (for input and output) so you can see how the tool works.

Rollup has been known for its use in a number of popular libraries like React, Babel, and Three.js. Thus, it may not be as user-friendly for developers working on small or medium-sized projects. Also, its extensive configuration options can be a drawback to those looking for a simpler solution.

WMR

WMR is a modern build tool created by the team that made Preact.js, the popular React alternative. It launched in 2020 and continues to be a viable option in modern projects.

🎯 Some of WMR’s strong features include:

• Preact support: Since it’s built by the same team maintaining Preact, WMR will be a natural fit for those building Preact projects, but it can also be used with other libraries.
• No configuration needed: Like Parcel and Webpack, you can use WMR without any configuration.
• Preact and prototypes: WMR is particularly useful if you’re already using Preact and can help in quickly building small to medium-sized projects or prototypes.
• Small size: WMR is a small build tool with a minimal footprint.

Drawbacks of WMR, as already implied, are the fact that it’s mainly designed for Preact users and might not work well with large projects.

SWC

SWC (or “Speedy Web Compiler”) is a Rust-based build tool that’s used by tools like Next.js, Parcel, Deno, and others. You can use it for both compilation and bundling.

🎯 Some of its standout features include:

• Rust and JavaScript: SWC works as a build tool for Rust code or JavaScript.
• Speed: SWC’s performance is one of its primary features, boasting 20x better compilation time compared to similar solutions.
• Use with Webpack and Jest: As SWC is a broader build solution, you can use it inside Webpack by means of a loader. It’s also compatible with Jest, the popular test suite.

One of the main drawbacks of SWC at the time of writing is the fact that it doesn’t yet support bundling. That feature is expected to ship eventually, though. So right now it’s mainly used for compiling, minifying, and transforming while integrating with Webpack for your bundles.

Rome

Rome is a new tool that falls into the category of next-level JavaScript build tools, advertised as a set of unified tools. It’s still a work in progress, so as of this writing it includes only a few major components in its toolchain.

🎯 Rome will include many of the features available in most other build tools but has some unique ones:

• Integrated toolchain: Rome intends to go beyond the basics, offering a linter, formatter, compiler, bundler, and test suite, all in a single toolset.
• Multi-language compiling: Rome will compile from JavaScript, TypeScript, JSX, and JSON.
• Centralized configuration: You can configure all of Rome’s tools from a single configuration file.
• Speed and scalability: Rome is designed for large, growing projects, with modular features that allow you to customize the toolchain to your needs.

Rome’s primary drawbacks are the fact that it’s new and its toolset is still in flux. It’s worth keeping an eye on, but probably not ready for any serious projects.

Turbo

Turbo is one of the industry’s newest JavaScript tools that’s actually a pair of tools: Turbopack (a bundler based on Rust) and Turborepo (a build system based on Go, but migrating to Rust soon).

It’s still in its infancy, but the Turbopack team view it as the natural successor to Webpack (it’s built by Vercel team members who originally built Webpack).

🎯 The main features of Turbopack and Turborepo include:

• Speed: Turbopack boasts significantly faster builds and server startup time compared to Webpack.
• Uses SWC under the hood: It uses SWC for its bundles, so it will support any ES features that SWC supports.
• TypeScript support: Turpoback is optimized for JavaScript and TypeScript and includes TypeScript support out-of-the-box.
• Designed for incremental adoption: Turborepo is designed to be easily added to any existing codebase.

Both Turborepo and Turbopack are still in early development, so you may want to hold off on using either in production. While they boast strong current and upcoming features, it’s probably best to use them only for experimental work.

Honorable mentions ⭐

The tools I’ve included above are the main ones you’ll want to investigate when considering a JavaScript build tool or bundler. There are, however, others that I won’t expand on but that are worth mentioning briefly:

• Snowpack: No longer maintained, but a viable option with the developers now recommending Vite instead.
• Microbundle: Zero-config bundler powered by Rollup.
• Packup: Zero-config bundler for Deno, inspired by Parcel.
• Lasso.js: Node.js-style bundler used by the engineering team at eBay.
• Grunt and Gulp: Older tools that are task runners, not build tools, the forerunners to modern solutions.
• Browserify: An older solution that allows you to require() modules in the browser like Node.js, but not as relevant with the advent of ES modules.

That wraps things up for this consideration of modern JavaScript build tools and bundlers. If you’re looking into using a build tool for projects going forward, I hope this list was an effective start to your research.

If you have questions about any of these build tools, feel free to ask in the comments below.