Release 0.24: Native Bun support

Today we're announcing the availability of the Primate 0.24 preview release. This release introduces native Bun support, enabling you to serve your applications significantly faster than before.

Bun is a new runtime based on JavaScriptCore and written in Zig. It has recently had its first stable version, and has seen an uptick in interest ever since.

If you're new to Primate, we recommend reading the Getting started page to get an idea of the framework.

Native Bun support

When Bun 1.0 came out, we were quick to test running Primate using Bun's NPM compatibility. As it turned out, running bun x primate works as expected and runs a Primate app without issues.

However, the real promise of Bun lies in its fast HTTP library implementation, Bun.serve. Bun's NPM compatibility is great, but to get real speed gains over Node, we have to use its native standard library.

As it turns out, Primate already uses a standard library of its own, rcompat. As Primate is not the only project using it, we decided to implement native Bun support into it and thus have Primate and other projects benefit from it. This release uses the latest release of rcompat, which uses Bun natively wherever possible and falls back to Node/NPM otherwise.

In addition to the core package, we have also patched @primate/store to use Bun's native bun:sqlite module.


To illustrate the difference in serving Primate with native Bun, we created a threeway benchmark: running Primate with NPM (npx primate), running it with Bun's NPM compatibility (bun x primate), and running it natively with Bun (bun --bun x primate).

Using the ab testing tool, we tested two scenarios, serving plain-text content and an SSR-rendered Svelte page.

Our command for benchmarking was ab -c 350 -n 100000 [url]. That is, send 100000 requests with a concurrency of 350 requests at a time.

The app we used for testing was the Primate template app. To replicate the benchmarks, clone that repository and run the app.

In the following benchmarks, the quantities are:


Command used ab -c 350 -n 100000 http://localhost:6161/benchmark

Server TT (s) RPS TPR (ms) TR (Kbytes/s)
npx primate 72.228 1384.50 0.722 809.88
bun x primate 72.688 1375.74 0.727 804.75
bun --bun x primate 18.488 5408.98 0.185 3169.33


Command used ab -c 350 -n 100000 http://localhost:6161/benchmark/svelte

Server TT (s) RPS TPR (ms) TR (Kbytes/s)
npx primate 117.646 850.01 1.176 2560.81
bun x primate 115.408 866.49 1.154 2610.48
bun --bun x primate 29.981 3335.40 0.300 10058.33


In upcoming releases, we'll continue to improve Primate's support for Bun, using native modules and functions wherever possible. Currently, if you rely on @primate/ws for WebSockets in your application, you would have to stick to NPM. Bun's native WebSocket implementation is radically different from the ws package which @primate/ws uses, and unifying them was deemed out of scope for this release. Please reach out if you specifically need WebSockets in your application so we can better prioritize our work.

Other changes

Consult the full changelog for a list of all relevant changes.

Next on the road

Some of the things we plan to tackle in the upcoming weeks are,

This list isn't exhaustive or binding. None, some or all of these features may be included in 0.25, and other features may be prioritized according to feedback.


If you like Primate, consider joining our channel #primate on

Otherwise, have a blast with the new version!