Rolldown, a new JavaScript/TypeScript bundler written in Rust, has emerged from VoidZero, the maintainers of projects such as Vite. Rolldown offers a high performance alternative to conventional bundlers with full compatibility for the Rollup plugin ecosystem. Designed as the next logical step for modern build workflows, Rolldown promises significant build time improvements while retaining familiar plugin interfaces.
Rolldown was designed primarily to be the underlying bundler within Vite to replace the existing Vite dependencies of esbuild and Rollup. It is also going to be used in the newly announced Vite+ project. A key difference between Rollup and Rolldown is that Rolldown is written in Rust and means it can leverage native multithreaded execution with fewer overheads than JavaScript-based tooling. According to the team behind the project, Rolldown can be ’10-30 times faster than Rollup’, and according to this post on X, it also beats esbuild by a large margin in their tests.
Rolldown’s API is deliberately compatible with Rollup’s plugin system, meaning most existing Rollup/Vite plugins should continue to work with minimal changes. It does however introduce features beyond Rollup’s scope, such as advanced chunk splitting, built-in transforms (TypeScript/JSX lowering), experimental CSS bundling, and experimental module federation. It is possible to find more about the notable rolldown features here.
A developer over on reddit has posted their real world performance metrics based on a front end project. They initially saw a 1.8x increase in performance by just swapping our rollup dependency for rolldown, and when questioned by another user about using the native plugins provided by rolldown, the performance difference jumped to 5x, this comes in lower than the 10-30 times faster quoted by the package authors, it is worth noting reddit post was 6 months ago so it would likely be using an older version of the library to the one available today.
Elsewhere in the community, Justin Schroeder posted on X earlier this year an explanation of why he thinks that Rolldown might be ‘the most important web project of the next 5-10 years’. He went on to praise rollup for being the ‘best and most comprehensive bundler to date’, but highlighted that performance from relying on JavaScript could be improved. The post mentions that esbuild demonstrated how a native bundler could be faster, but isn’t compatible with Rollup and that is where Rolldown provides both the speed and compatibility that is needed.
Rolldown is an open-source bundler written in Rust, engineered for speed, compatibility, and next-gen bundling features. It supports Rollup-style plugins, delivers substantial performance gains for large builds, and introduces tooling that addresses modern scaling requirements. If you’re building large-scale apps, monorepos, or frameworks and want faster builds without rewriting your plugin layer, Rolldown is a compelling choice. Yet for smaller libraries or simpler pipelines, the simpler tooling of tsup or esbuild may remain sufficient.
