Kenton Varda

My partner Jade turned her old work into a music video and it's so good...

Jade Wang@jadewang.me

I made a techno remix out of a song I recorded with an acoustic guitar in 2011, and asked Opus 5.5 for a music video with a JavaScript-forward art style. (It’s DDR optimized. Anyone else here plays DDR and is interested in steps?) 🧵

I know AI is unpopular here compared to the other site. But can we agree this is the best possible use of AI media generation? An individual bringing their own original work to life, just for the sake of being awesome? I, for one, want to see more of this!

18 May

My wife @jadewang.me wrote a collection of poetry that is designed to be read by AI. To be clear, it is NOT written by AI. Jade wrote everything herself. But it contains puzzles that very few humans have enough context to figure out, but most frontier models do.

Jade Wang@jadewang.me

spacesleftblank.com: autobiographical poetry (immigration raid -> neuroscience -> NASA -> startups) human written (by me) intended to be experienced inside a conversation with an AI that also asks questions about consciousness

18 May

Per the instructions on the site, you can upload the PDF to an AI and ask for "adaptive footnotes" to see what it sees. Pretty interesting, and as far as we know no one has done this before.

blog.cloudflare.comSandboxing AI agents, 100x fasterWe’re introducing Dynamic Workers, which allow you to execute AI-generated code in secure, lightweight isolates. This approach is 100 times faster than traditional containers, enabling millisecond sta...

Big launch today: Dynamic Workers are now in Open Beta, all paid Workers users have access. Secure sandboxes that start ~100x faster than a container and use 1/10 the memory, so you can start one up on-demand to handle one AI chat message and then throw it away. blog.cloudflare.com/dynamic-work...

This is all made possible by the isolation model that Cloudflare Workers has been built on since the beginning: isolates, not containers. It's kinda crazy how the thing we've been doing differently and perfecting for 9 years is suddenly so relevant to AI.

youtube.comLet's put the AI in lots of little boxes - Kenton Varda, Cloudflare Connect 2025YouTube video by Cloudflare Developers

By the way, I gave a talk a few months ago on the future of agents writing code and why Dynamic Workers are ideal for this use case. If you like to consume information in video form, check it out! www.youtube.com/watch?v=xUj4...

That said, if you are working with existing HTTP-based client libraries (which you want to inject into the sandbox), then perhaps HTTP filtering is easier to get started with.

developers.cloudflare.comEgress controlRestrict, intercept, and audit outbound network access for dynamic Workers.

Very well, if you want that, we have the best "egress control" possible: You can *write a Worker* that handles egress from your sandbox. Inject credentials, filter requests, arbitrarily rewrite, whatever. It's code, you can do anything. developers.cloudflare.com/dynamic-work...

You can define the RPC interface to support exactly the operations you want to support, so it's totally obvious what the agent can and can't do. Then you just tell the agent the TypeScript type definition of the interface and let it code.

developers.cloudflare.comBindingsGive Dynamic Workers access to external APIs.

This is *much* cleaner than intercepting HTTP requests, and easier for the agent to understand, too. Check out the docs here: developers.cloudflare.com/dynamic-work...

But that's only half of it. Lots of people today are talking about keeping API keys out of your agent sandbox by injecting them into requests on the way out. You can do that with Dynamic Workers, but you can also do *much better*.

Dynamic Workers let you block internet access entirely, and then constructively grant the sandbox access to specific TypeScript interfaces, via Cap'n Web RPC. Essentially you can invent your own "Workers bindings" to give it, pointing at whatever you want. A chat room. A git repo. Etc.

Agents should interact with the world by writing code, not tool calls. Just like you might write a little bash script to do a task. But starting a container for every end user is impractical. Dynamic Workers solve this -- now millions of end users can each have their own agent, writing code.

youtube.comMartial arts robots dazzle at 2026 Spring Festival Gala #CoolChina #springfestival2026YouTube video by CGTN

18 Feb

I don't know why this robot performance -- casually dropped into the CMG Spring Festival Gala -- isn't getting more attention. Stunning advancement in robot technology. Feels like Unitree suddenly passed and then lapped Boston Dynamics in the past year? And lol@Tesla. www.youtube.com/watch?v=mUml...

Meanwhile Tesla over here bragging about how their robots can now take a leisurely jog without falling. x.com/Tesla_Optimu...

Boston Dynamics is better than Tesla but only just sort of accomplishing moves in the shop that Unitree's robots can apparently do reliably in a live choreographed performance. www.youtube.com/watch?v=UNor...

youtube.comAtlas Airborne | Boston Dynamics & @rai-instYouTube video by Boston Dynamics

youtube.comMartial arts robots dazzle at 2026 Spring Festival Gala #CoolChina #springfestival2026YouTube video by CGTN

18 Feb

youtube.com2025 vs. 2026: Humanoid robots stage kung fu comeback at Chinese New Year Gala #CoolChinaYouTube video by CGTN

18 Feb

Last year vs. this year. www.youtube.com/shorts/td5iC...

Kenton Varda reposted

Minnesota Star Tribune

@startribune.com

22 Jan

Tomorrow’s front page of the Minnesota Star Tribune: Jan. 23, 2026

Kenton Varda reposted

Margaret Killjoy

@margaret.bsky.social

22 Jan

I came to Minneapolis to report on what's going on, and one of the main questions I showed up with is "just what is the scale of the resistance?" After all, we're all used to the news calling Portland a "war zone" or whatever when it's just some protests in one part of town.

Kenton Varda reposted

Street Sharks Explained 🇨🇺🇵🇸🏳️‍🌈

@gaykwon.bsky.social

15 Jan

This dude is intense and correct

8 Dec 2025

Happy 10th Birthday to this Onion headline.

13 Nov 2025

I was looking for a sound clip from the 1983 arcade game, Sinistar, and instead I got... whatever this is.

blog.cloudflare.comAnnouncing Workers automatic tracing -- now in open betaCloudflare Workers' support for automatic tracing is now in open beta! Export traces to any OpenTelemetry-compatible provider for deeper application observability -- no code changes required

12 Nov 2025

Whelp. I'm locked out of X because it insists I re-enroll my security key (which I haven't used in years, I always use the authenticator app), and when I try to do that, it just loops back and prompts me to do it again. Great.

Kenton Varda reposted

Jeremy Morrell

@jeremymorrell.dev

28 Oct 2025

It launched! Get traces for your app with zero code changes. No libraries, no SDK, no config. Traces show up in your dash or you can export them to your favorite o11y vendor over OTLP blog.cloudflare.com/workers-trac...

14 Oct 2025

Those benchmarks from @t3.gg revealed some interesting issues in Workers. Happy to say it's all fixed now, save for some lingering next.js-specific stuff we're continuing to work on. Thanks for the reproducible test cases, @t3.gg. Excessive details in blog post: blog.cloudflare.com/unpacking-cl...

blog.cloudflare.comCode Mode: the better way to use MCPIt turns out we've all been using MCP wrong. Most agents today use MCP by exposing the

Hey Bluesky, I know how people here just LOVE everything AI, so I wanted to show you what @threepointone.bsky.social and I have been up to. We made an agent that calls MCP not as "tools", but by converting the tools into a TypeScript API, and writing code against that. blog.cloudflare.com/code-mode/

Dynamic Worker loading, of course, has applications far beyond just MCP or AI. It's a general-purpose capability-based sandboxing mechanism. If I had more time I'd build Sandstorm.io 2.0 on this...

Anyway, please don't murder me for the quip that kinda sorta compares LLMs to Shakespeare. /me runs away

blog.cloudflare.comCode Mode: the better way to use MCPIt turns out we've all been using MCP wrong. Most agents today use MCP by exposing the

This works better than direct tool calls becaues LLMs actually have WAY more training data for writing code than for calling tools. After all, tool-calling is a sort of artificial thing just for LLMs. Code is everywhere.

developers.cloudflare.comDynamic Worker LoadersThe Dynamic Worker Loader API, which allows dynamically spawning isolates that run arbitrary code.

This is all based on a new Workers Runtime feature called Dynamic Worker Loading, which lets you dynamically load arbitrary code into a fresh isolate. Isolates are wayyyyyy cheaper and faster to load than containers. Perfect for executing one-offs. developers.cloudflare.com/workers/runt...

23 Sept 2025

Did search. Would eat.

xkcd title text@xkcd-titletext.bsky.social

Title text: "If you want to see true audacity, do an image search for 'Altoona-style pizza.'" Alt text: https://explainxkcd.com/3142#Transcript

23 Sept 2025

I think adding the .map() thing was worth it just for the engagement on these threads lol.

I don't have a problem with making new RPC systems! I can stop any time I want! But I don't want to. So I made a new one for you. It's called Cap'n Web. It's like Cap'n Proto RPC, except focused on working great in browsers and JavaScript/TypeScript servers. blog.cloudflare.com/capnweb-java...

Special thanks to @threepointone.bsky.social for prompting the AI slop image at the top of this thread, which is absolutely not official Cloudflare marketing material, but I rather like it.

Also thanks to @southpolesteve.com for help with the blog post, writing examples, and highlighting the fact that this is sort of an alternative to GraphQL -- which convinced me to implement the .map() fetaure.

And all this with no boilerplate. Seriously, check out the examples in the post and readme. github.com/cloudflare/c...

blog.cloudflare.comCap'n Web: A new RPC system for browsers and web serversCap'n Web is a new open source, JavaScript-native RPC protocol for use in browsers and web servers. It provides the expressive power of Cap'n Proto, but with no schemas and no boilerplate.

Just a gift to the internet. Use it as you please. I've been using it in a React app I've been vibe-coding and been pleased with the results. The AI doesn't have to understand it since it just looks like a regular JavaScript API was magically transported over the network.

2. In Cap'n Web, if you have a promise for an array, you can call .map() on it to apply a transformation to every element of the array. The way this works is WILD; see the blog post for more. blog.cloudflare.com/capnweb-java...

Cap'n Web integrates nicely with Cloudflare Workers' built-in RPC, so you can take a Workers-native stub (including Durable Object stubs) and just pass it over Cap'n Web to a client. Proxying is arranged automatically. (But again, you can use it with any runtime.)

You also get Promise Pipelining, which means that if you need to make a chain of calls, where one call's inputs incorporate the previous call's results, you can do that in one network round trip. In fact, Cap'n Web features two major advances over Cap'n Proto in this regard.

1. In Cap'n Proto, you could only pipeline on stubs. In Cap'n Web, if you have a promise for, say, a number, you can put that promise into a subsequent call where a number is needed. The resolution is automatically substituted in before the dependent call is delivered.

Cap'n Web does NOT use zero-copy binary serialization like Cap'n Proto. It's just JSON underneath. This may surprise people, but the serialization was never my favorite part of Cap'n Proto. The RPC system has always been the main point.

github.comGitHub - cloudflare/capnweb: JavaScript/TypeScript-native, low-boilerplate, object-capability RPC systemJavaScript/TypeScript-native, low-boilerplate, object-capability RPC system - cloudflare/capnweb

What's so great about the RPC? Well, it supports object capabilities (pass-by-reference). You can pass a function over RPC; the remote end gets a stub, which, when called, calls back over RPC to the original function. You can pass objects with methods in the same way.

Here's the GitHub. It's pure JavaScript/TypeScript. It's MIT-licensed. It works in every modern JavaScript environment (not just Cloudflare Workers). The whole library has zero dependencies and compresses (minify+gzip) to under 10KiB of JavaScript. github.com/cloudflare/c...