Next.js: SWC Polyfill Power-Up and Future Performance Gains
A major development day with 18 merged PRs bringing automatic polyfill support through experimental.swcEnvOptions, significant Turbopack performance optimizations, and improved developer experience features. Key contributors include banchichen adding SWC preset-env configuration, sokra with custom Future implementations for better performance, and lukesandberg optimizing memory usage in Turbopack.
Duration: PT3M57S
Episode overview
This episode is a short developer briefing from Next.js.
It explains recent repository work in plain language.
- Show: Next.js
- Published: 2026-04-04T10:02:52Z
- Audio duration: PT3M57S
Transcript excerpt
This excerpt keeps the crawler page concise. Listen to the episode or use the RSS feed for the full update.
Hey there, Next.js developers! Welcome back to another episode of the Next.js podcast. I'm your host, and wow, what a packed day we have to dive into! April 4th brought us eighteen merged pull requests and a whole lot of exciting improvements that I can't wait to share with you.
Let's jump right into the big story of the day - and this one's pretty exciting if you've ever wrestled with polyfills. Banchichen just landed a fantastic new feature called experimental.swcEnvOptions that brings automatic polyfill injection back to Next.js! Remember how we used to have this with Babel's preset-env?…
Here's what makes this so cool - instead of manually importing core-js and bloating your bundle, or switching back to Babel and losing SWC's speed, you can now configure automatic polyfills right in your Next config. Just add experimental.swcEnvOptions with mode set to 'usage' and specify your core-js version, and…
Now, speaking of performance, Tobias Koppers has been doing some serious under-the-hood optimization work. He replaced a bunch of async functions with hand-written Future implementations, and I know that sounds super technical, but here's why you should care - it makes the binary…
Luke…
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