Why Turbopack in Next.js 15.3 Could Supercharge Your Frontend Build Speed

Next.js 15.3 just released, supporting Turbopack.

Turbopack is a Rust‑based JavaScript bundler for TypeScript and React server components, created by Webpack inventor Tobias Koppers, and its speed far exceeds its predecessor.

Since its October 2022 launch, Turbopack’s production‑ready progress was slow, but in the newly released Next.js 15.3 it passed over 99 % of tests, and the Next.js team says it can be used in production.

The team advises that if your app works with Turbopack in development, it should run unchanged in production, yet warns that because Turbopack is still in alpha, it is not recommended for critical production workloads.

Turbopack’s performance scales with CPU core count; Vercel claims it is 28 % faster than Webpack on a 4‑core machine and 83 % faster on a 30‑core machine.

Another option is Rspack, also built with Rust but with better Webpack compatibility; Vercel says the next‑rspack adapter passes 96 % of tests, which may embarrass Vercel since Turbopack is its internal project.

According to Rspack developers, Turbopack redesigns architecture and configuration, bringing benefits but higher migration cost for projects that rely on Webpack’s extensive ecosystem.

Turbopack is moving toward full compatibility with Next.js.

Other new features in Next.js 15.3 include client‑side detection hooks for monitoring and analytics, new navigation hooks to improve client routing, and an enhanced Next.js TypeScript language server plugin that reportedly speeds up about 60 %.