Bun 1.4 rewrites from Zig to Rust, cuts memory by up to 48%

It's weird their promotional video repeats "you can do <million things> without installing dependencies", if I want headless browser testing is that wrong to install a project that offers that?

Why would I want everything reimplemented in this massive binary? Why would Bun be anymore in touch with nuances of all these different technologies then individual projects dedicated to their own speciality?

JS Runtime, Package Manager, Test Runner (both unit and headless browser), Bundler, JSX, PosgreSQL/MySQL/SQLite drivers, S3 client, Redis client, Formatter, Linter, etc.

Not to mention parsers for YAML, TOML, Markdown which are easily three separate projects worth of complexity in their own right.

I guess one clear downside is to get all these great features they're pushing for 1.4 you needed to wait until everything was ready. Given 1.3 was pushed out in October 2025, a 10 month release cycle across so many large technologies is tough. Before you give a pass because of the Rust rewrite Bun 1.2 was released in January 2025

I have to respect Jarred knows how to work the algorithm, 10 carefully crafted X teaser posts for this release spaced out over 72 hours https://xcancel.com/jarredsumner

This is a huge win for Bun & Anthropic. I've been keeping an eye on Bun development cycle since they announced the Rust rewrite and the huge drama and backlash it generated. They seem to be proving the skeptics wrong with this release.

I recently pivoted to Rust for the backend development, after getting tired of the nodejs ecosystem fragmentation and how fragile things feel. Bun seems very interesting since it allows you to do so many things without pulling in 3rd party libraries and bundlers? Is anybody using it instead of nodejs? how's the experience so far? I might have to give it a try.

Yes, I know there's probably better options than Rust for building APIs, but I wanted to learn it, so why not?

Announcing that the SSR memory leak is gone as part of a product launch is wild.

> Bun is not 100% compatible with Node.js yet. In practice, much of the existing JavaScript ecosystem just works.

I don't care about 100% compatibility. NodeJS is a standard but dead to me.

I rather have faster feedback loop and less development/build/test time than worrying about Node.JS compatibility.

Bun is the answer for my flow.

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Bun might as well promote itself as the total replacement of Node.JS, and I will still hop in.

I like how the "over 10 MB smaller" is dubbed, sure the video was recorded some time ago and that number changed.

https://youtu.be/i38DgEuaJwM?si=6oKAysKoRDPCihsL&t=176

every couple years someone rewrites the whole toolchain and we collectively agree the last one was the mistake. good to know the cycle still works.