Smoking that Rspack

Today’s issue: Evan You’s Eagle Scout project, async’s broken promises, and an AI agent destroying all of a company’s production data (again).

Welcome to #481.

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Smoking that Rspack

Rspack 2.0 shipped last week with a bold new vision to become more than “just a faster webpack.”

And that’s an interesting shift for a project whose sole branding for the past two years has been: “we are a faster webpack.”

But it makes sense. Rspack’s initial pitch was that its Rust-based build tool would provide a 10x faster version of webpack that was still compatible with the webpack API and ecosystem. And since launching v1.0 in Aug 2024, they’ve implemented all of webpack’s core capabilities and plugin APIs, added modern features like incremental builds and persistent cache, and seen their npm downloads grow from 100k to 5 million per week.

So Rspack 2.0 is about finding new mountains to climb beyond webpack-land, by introducing defaults, API design, and build outputs that are “better aligned with modern JavaScript development” and come with first-class support for agents.

Here’s what that looks like in this release:

• More perf upgrades. Builds are ~10% faster than v1.7 and ~2x faster than 1.0. With persistent cache enabled, the SWC minimizer now caches hits for another ~50% speedup, and memory usage drops by 20%. And @rspack/dev-server went from 192 npm dependencies to 1.

• Grown-up ESM support. Rspack’s core packages are now pure ESM. You also get proper import.meta handling, import defer support, and a new modern-module output type for library builds that produces output downstream tools can actually tree shake.

• Smarter tree shaking. CommonJS destructuring, inline dynamic import() access, and Module Federation shared dependencies are all properly analyzed and pruned now. There’s also experimental support for the #__NO_SIDE_EFFECTS__ compiler annotation, so you can mark functions as side-effect-free and let the bundler clean up after you.

Bottom Line: Rspack has spent the last two years earning webpack developers’ trust by not breaking anything. Now it’s using that credibility to add new features and expand beyond the webpack ecosystem into a more general JS toolchain with packages like Rslib, Rsbuild and Rsdoctor.

And since the world cares less about webpack than ever, that’s probably a smart move.

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const petName = 'Leo'
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const reminderTemplate = '{NAME} is due for another visit. Please call us so we can set up a new appointment. We look forward to seeing you and {NAME} soon.'

const reminder = reminderTemplate.replace(placeholder, petName)

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1. Deno just launched Fresh 2.3 with View Transitions and zero JavaScript by default (but for real this time).

2. Mat Marquis has been waiting 14 years to write this article about the end of responsive images. I’ve been waiting 14 years to go back to the dentist, so I get it.

3. He helped React take over the web… and he just joined Expo. Check out this blog post from Seth Webster about what he thinks Expo will become. [sponsored]

4. Animata is a collection of 158+ animated React components you can copy into any project.

5. The VoidZero team wrote about how they made the Angular compiler 20x faster using AI. And apparently the whole thing was part of Evan You’s Eagle Scout project.

6. Slackbot demo - Meet the AI agent built right into Slack. Ask questions, automate tasks, and get answers grounded in your team’s actual context. No extra tools, no tab switching, no setup required. [sponsored]

7. Arkar Min Aung wrote a surprisingly interesting and interactive article about compressing AI vectors to 2–4 bits per number without losing accuracy.

8. Josh Segall wrote a good breakdown of what async promised vs what it delivered. But maybe the real async was the friends we made along the way.

9. Build dynamic forms that work your way. With SurveyJS, you get a fully customizable JavaScript form builder that integrates seamlessly with any backend—no vendor lock-in or usage limits. [sponsored]

10. The Chrome team released The Prompt API, which lets you send natural language requests to Gemini Nano in the browser. Another daily reminder that I should’ve bought more Google stock.

11. muffin wrote about the woes of sanitizing SVGs.

12. Jer Crane wrote a Twitter article about how an AI agent just destroyed our production data. Dario is willing to concede that software engineers will maybe have jobs for another two weeks now.

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const petName = 'Leo'
const placeholder = '{NAME}'
const reminderTemplate = '{NAME} is due for another visit. Please call us so we can set up a new appointment. We look forward to seeing you and {NAME} soon.'

const reminder = reminderTemplate.replaceAll(placeholder, petName)