I built a Rust-based image compressor, WASM binary, and SvelteKit app! I wanted to see how far I could go using only coding agents. I did not write any code by hand. After 520 agents, 350M tokens, and $287 I can now say… extremely far.

My library, pixo, has zero runtime dependencies. All algorithms were implemented from scratch. It achieves performance close to a 30-year-old highly optimized C/Assembly library. It has 900+ tests with 85% coverage. No slop or vibes here.

Here’s a few interesting things coding agents did for me: 1. Created benchmarks against similar tools, found performance gaps, and then fixed them 2. Optimized the WASM binary, looking up the right config/flags to use, shrinking the size 3. Measured code coverage, found gaps, and then wrote tests based on the missing coverage 4. Found public domain images to scaffold a comprehensive test suite 5. Researched compression specs and RFCs to validate correctness of all tests 6. Added CI for linting, testing, and generating WASM binaries What a time to be alive.

I wrote up a very detailed post about how I built pixo and how I'm thinking about the future of software. I don't really expect people to use the library, but open to contributions or suggestions on how to make it better!

Btw if anyone wants to roast the Rust code, please do. If you open some issues, I'll have Cursor fix them 🫡

When you say 520 agents ? That means like different agent chats started ?

Yep!

This is pretty amazing! And inspiring

glad the word is spreading it’s insane what we can do now haven’t written code in 10 months barely even reading diffs

I would still read the diffs 😄

i did early on, but then started trusting them especially gpt-5-high ones depends on the stake of the app tho of course. i wouldn’t write cursor features without checking them. 😂

this is the future of dev work imo, crazy that $287 gets you a fully functional app without writing a single line of code yourself

And that's API pricing, this would be in the $200/mo Cursor plan!

What about time? How much total time did this take end-to-end?

About 5 days over the holidays. Have made a few tweaks since then. A good chunk of that time was away from the keyboard too, reading books to my daughter 😄

How did you create 520 agents?

extremely good aesthetics

🖤

Great read. Thanks!

Thank you for the really lengthy blog post. It is literally a masterclass in modern engineering. You're pioneering this and appreciate you talking about it publicly. My favorite part of the blog post is where you mentioned that someone who was really good at English might not get to the same results, and you specifically called upon your computer science background and the understanding of certain concepts. Not that you're writing the assembly by hand, but that you're able to guide an agent to do that for you. I had a similar epiphany when making a multiplayer soccer game, and I've never written a line of code in Rust and was really shocked at what I could do in 12 days

couldn't you have used as a reference repo and saved a lot of tokens and time?

Check out the benchmarks and codebase comparisons! Squoosh with your png/jpeg codec of choice was still a much larger binary. Happy to be proven wrong 😁 But as mentioned in the post, I don’t expect that people will adopt pixo.

had a similar experience while building why trust shady websites when you can spin up your own version in a couple hours

Had a very similar experience with - live annotation tool for Linux (on wayland). Was quite fun, but then I kept adding user-requested features, and some of my own. Totally fun :)

@ibrahimsuta Very cool idea!

the result looks good but 520 agents and 350M tokens ($287) seem expensive for that app yeah, hiring a dev would cost more, but as a developer, $287 is still a lot

$200/mo plan for almost 40,000 lines of high quality code is insane value. This is alien technology 😄

epic

damn it, i want to work at cursor now

Pretty cool

I use Composer 1 as my default model, and I‘m pretty happy for most of my tasks. Why did you prefer Codex and Opus for your development? Did you use it primarily for long running agentic tasks?

Yeah, everything here was long running. I did use Composer when making some of the design updates on the web app.

Oh man next years gonna be so fun and the year after that and the year after that

bro really bypassed my gen ai muted terms with "coding agents"

same, I’m writing a hypervisor type 2 like firecracker in Go without CGO, and with support also for MacOS VZ. I’m almost done and it has been probably 3 weeks since I started.

Awesome idea

Nice work! Just want to echo the exact same experience in a different full stack app. It is so incredibly fun that you can build so much without writing *any* of the code. Only thing I’d emphasize is for certain things you benefit a lot from tons of specs. A few more takeaways and my prompts are here:

This. Is. Amazing. You don't understand how epic this is

crazy

Wow, you vibe-coded a perfect web app in rust. That's really impressive.

didn’t write any code by hand👇🏼 check it out ❤️

Super nice, I completely agree that these models opening a new era for products :)

Great stuff!

Hmm how much of the generated code is just squoosh?

The better question is: how much of the generated code is similar to the *codecs* that sqooush can choose from? e.g. mozjpeg. Could be interesting to compare, although mozjpeg is C/Assembly and this is Rust. That codec has 30 years of bug fixes/improvements/perf optimizations!

I’ve been taking the challenge to do that using only using a phone while on vacation. Building a book reader app with cursor agents, v0, and chrome browser on iOS

this is awesome

Love the UI!

Thank you! Fun fact, this was the first version of the UI the model generated. It technically works but it's boring and crowded. Having good taste matters 😄

Yeah, I saw. I mean, that's the difference between using it and just skipping it, the final UI looks so polished and really feels like something you want to use. It's a night-and-day difference and feels so pleasant.

all the tools i love are used in this

Rust is a lot of fun, big fan

I did a similar test but with rust, the language is not a barrier anymore, I have even prompted phyton scripts, love opus 4.5 inside cursor so much