Deno

A modern runtime for JavaScript and TypeScript

[Deno @deno_land]

Introducing Claw Patrol!

A security firewall for AI agents. It sits between your agents and production, parsing and gating HTTP, SQL, Kubernetes, and SSH on the wire.

Built from our experience giving ops agents production access without sharing credentials.

MIT licensed.

[Ryan Dahl @rough__sea]

JavaScript trademark update: We've consented to another request from Oracle to extend the timeline. This is their 5th extension request.

[Ryan Dahl @rough__sea]

`deno compile` will soon support using quickjs instead of v8. dramatically reduces outputted binary size

https://t.co/FZiK3C4ym7

[Bartek Iwańczuk @biwanczuk]

Nice improvement to Bun’s startup path. Our measurements match the claim for empty programs (~7.5 ms for Bun vs ~10 ms for @deno_land).

Once you run a realistic program, though, the difference disappears 👇

In other words, this is mostly an optimization for startup overhead rather than application execution.

[Deno @deno_land]

https://t.co/ZrmTeHtAQJ

[Deno @deno_land]

Another week, another patch release 🦕

Deno v2.9.4: 47 bug fixes plus a handful of perf wins (FxHash hot maps, smaller snapshots, slimmer AppImages).

See you next week!

[Deno @deno_land]

https://t.co/PqkVQh62lR

[Deno @deno_land]

🦕 Deno v2.9.3 is out! 50+ fixes plus a batch of perf wins:

- Faster crypto.randomUUID() via batched generation
- Removed quadratic line buffering in EventSource (fetch)
- Cached compiled glob matchers in node:fs
- Fast path for fs.cp
- Speed up sqlite.StatementSync.all() / .run()

👉 deno upgrade

[Deno @deno_land]

https://t.co/4ZOTa8k8en

[Deno @deno_land]

Deno v2.9.2 is out with perf improvements:
- ReadableStream async iterator now has a sync fast path
- queueMicrotask uses V8 natively
- zero-copy async writes for node streams
- SIMD JSON indexing for npm packuments
- faster worker message passing

Plus 39 bug fixes and 13 improvements to Deno Desktop

deno upgrade

[Better Stack @BetterStackHQ]

Deno 2.9 shipped deno desktop: native desktop apps in pure TypeScript. No Electron, no Chromium.

[Deno @deno_land]

https://t.co/vDxn7BSOpy
~4.5% idle RSS improvement
(would be ~10% if we disabled ASLR like bun does - we won't)

[Deno @deno_land]

Deno 2.9.1 is out 🦕

deno desktop gets --desktop type-checking and no more startup black flash (the window now reveals on first paint).

Plus 47 fixes across npm client, fetch, node compat, and more.

deno upgrade

[Deno @deno_land]

Deno 2.9 is released!

› deno desktop
› 2x faster startup, 2x less memory
› min-release-age by default
› css imports
› import npm/pnpm/yarn/bun lockfiles
› deno link/unlink
› deno bundle emits rolled-up d.ts

🦕 full release notes: https://t.co/OlGPZQj7vy

[Deno @deno_land]

Landing now, importer by importer:
https://t.co/JrD1u0eh6L
https://t.co/kS5E2hUBgY

[Deno @deno_land]

In Deno 2.9, coming next week, migrating from other package managers will be seamless.

Deno will understand the lockfiles you already have from npm, yarn, pnpm, and bun.

[Deno @deno_land]

Workspaces are drop-in too. npm, yarn, and bun keep their workspaces in package.json, so they just work. catalog: and the rest are supported.

Only pnpm needs a small migration, since it keeps workspace config in pnpm-workspace.yaml, which Deno converts to deno.json for you.

[Deno @deno_land]

docs for deno desktop: https://t.co/mVseC9115Y

[Deno @deno_land]

`deno desktop` has landed in main. You can try it out by running `deno upgrade canary`
- Mac, Linux, and Windows support
- Can generate pkg and msi installers
- Supports cross-compile (generate .exe from mac)
- Supports chrome (CEF) or native Webview for smaller binaries

[Deno @deno_land]

example app https://t.co/RY0EoUg8Sl

[Deno @deno_land]

`deno desktop` has landed in main. You can try it out by running `deno upgrade canary`
- Mac, Linux, and Windows support
- Can generate pkg and msi installers
- Supports cross-compile (generate .exe from mac)
- Supports chrome (CEF) or native Webview for smaller binaries

[Bartek Iwańczuk @biwanczuk]

Deno 2.9 will ship with CSS import support.

A CSS import used to kill module loading in Deno before a single line of your code ran.

It will now give you a real CSSStyleSheet, so you can run unmodified browser module graphs for SSR and web component testing.