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ekzhang

Re:A Topological Picture Book, Rendered on Tuesday September 08, 2026 @08:20PM (#49619063)
The spacing and style of the hand sketched lines are really perfect. Was it hard get such clean drawings, even using principal curvature fields?
Re:Inflect-Micro-v2: complete voice in 9.36M parameters on Tuesday July 28, 2026 @12:22PM (#49086256)
Maybe try using https://www.npmjs.com/package/@jax-js/onnx ? It supports most ONNX ops and should be drop-in replacement, e.g., https://jax-js.com/d-fine

Disclaimer: I am the author

I don’t think this is straightforward but it may be a skill issue on my part. It would require dockerizing headless Chrome with WebGPU support and dynamically injecting custom bundled JavaScript into the page, then extracting the results with Chrome IPC
Yes, we are actively working on it! The goal is to be a full ML research library, not just a model inference runtime. You can join the Discord to follow along
Hm okay, seems like an interesting set of benchmarks — let me know if there’s anything I can do to help make jax-js more compatible with your docker setup
Firefox doesn’t support WebGPU yet, you can run programs in the REPL through other backends like Wasm/WebGL: https://jax-js.com/repl

See: https://caniuse.com/webgpu

Since ONNX is just a model data format, you can actually parse and run ONNX files in jax-js as well. Here’s an example of running DETR ResNet-50 from Xenova’s transformers.js checkpoint in jax-js

https://jax-js.com/detr-resnet-50

I don’t think I intend to support everything in ONNX right now, especially quant/dequant, but eventually it would be interesting to see if we can help accelerate transformers.js with a jax-js backend + goodies like kernel fusion

jax-js is more trying to explore being an ML research library, rather than ONNX which is a runtime for exported models

I don’t think tf.tidy() is a sound API under jvp/grad transformations, also it prevents you from using async which makes it incompatible with GPU backends (or blocks the page), a pretty big issue. https://github.com/tensorflow/tfjs/issues/5468

Thanks for the feedback though, just explaining how we arrived at this API. I hope you’d at least try it out — hopefully you will see when developing that the refs are more flexible than alternatives.

For sure! It looks like this is benchmarking the autodiff cpu time, not the actual kernels though, which (correct me if I’m wrong) isn’t really relevant for an ML library — it’s more for if you have a really complex scientific expression
Re:Show HN: jax-js, an ML library and compiler for the web on Thursday December 18, 2025 @11:18AM (#46314660)
Wanted to share this library that I'm open-sourcing now after working on it for the past year.

You write code like in JAX/NumPy, but it’s fully interactive on the frontend and compiles down to shaders on the user’s GPU (with WebGPU). So far I’ve used it for purely frontend-only ML demos. https://jax-js.com/mobileclip

Thanks! I think that's a great idea. Containers are nice, but there's nothing quite like a "real" VM system in terms of learning + developing, and they can be very cheap if you're OK with the performance hit from nested virtualization :)

Another idea I had is to customize the rootfs. It boots Alpine right now, but should be trivial to change it to anything else (and it only takes ~5 seconds to build!).

Show HN: SSH-hypervisor – like SSH, but each user gets their own microVM

https://ekzhang.substack.com/p/ssh-hypervisor-simcity-for-vms

This is a project I made over the weekend. What if when you SSH'd into a machine, instead of giving you a user login, it would provision a new microVM just for you?It's like a little SimCity for VMs.This turned out to be a lot of fun, and I've wanted to make my own custom SSH server for a while now, with its fancy progress bars and color animations. The hardest part was definitely debugging VM...

( Read More... | 4 comments | 3 points | on HN )
Hello! Thrilled to be sharing something I've worked on for the past 8 months at Modal — a cloud, GPU notebooks product.

We wanted to improve the Jupyter Notebook experience while offering high-performance, cloud compute. So we sought out to fix some of the problems in cloud offerings for notebooks, and we ended up rebuilding a lot of the interface ourselves. This means you can do things like:

- Within the same notebook, swap from CPU to GPU, and the kernel will restart in seconds while keeping your work.

- Use _lots_ of hardware: up to 8x H100/B200 GPUs, not just one.

- Automatic idle shutdown (configurable timeout) so you don't get a huge bill / forget to stop your notebook.

- Real-time collaborative editing.

- Integrations with Pyright and Ruff for a better IDE-like experience.

Unlike Google Colab, we are a full cloud offering, so you can integrate with the rest of the Modal platform — use custom images, attach persistent volumes and so on. We've heard these are the actual, boring but really important features you need to do experimental work in notebooks.

Happy to hear any feedback! Would love for you to try it out.

Re:How the jax.jit() JIT compiler works in jax-js on Wednesday May 14, 2025 @01:51PM (#43987353)
Hello - I wanted to share a bit about an open-source project I’ve been working on, building a fundamental library for ML and numerical computing in the browser.

There are different tradeoffs here, but I’d like to replicate the speed and ergonomics of Python libraries with NumPy/PyTorch/JAX without the difficulty of distribution. jax-js is lightweight enough to be embedded in a website, but optimized to take advantage of tech like Wasm and WebGPU.

Let me know if you have any feedback on this compiler design. It’s working well and faster than tfjs at matrix multiplication, while having kernel fusion as well.

Re:A new home for Python-build-standalone on Tuesday December 03, 2024 @10:06PM (#42314157)
Just want to mention that these standalone python builds have been super important for simplifying a lot of dev tooling, even if users may not see it directly — I work for a cloud infrastructure company, and they’re what allow us to give users a one-line way of adding Python to any Docker image they desire. It’s helpful to have reproducible, standalone Python builds of this quality (and release transparency). Thanks y’all for taking this on.
Re:Static IPs for Serverless Containers on Tuesday December 03, 2024 @08:45AM (#42305958)
Sorry, just realized the misunderstanding. To clarify Modal still uses the kernel WireGuard module. The userspace part that’s in Go and not in other languages that we use is the wgctrl library.
Re:Static IPs for Serverless Containers on Monday December 02, 2024 @10:26PM (#42302830)
This is it. I like Rust a lot, but you gotta pick the right tool for the job sometimes
Re:Static IPs for Serverless Containers on Monday December 02, 2024 @08:05PM (#42302063)
Right, vprox servers act as multiplexed NAT instances with a VPN attached. You do still need the VPN part though since our containers run around the world, in multiple regions and availability zones. Setting the gateway to a machine running fck-nat would only work if that machine is in the same subnet (e.g., for AWS, in one availability zone).

The other features that were hard requirements for us were multi-tenancy and high availability / failover.

By the way, fck-nat is just a basic shell script that sets the `ip_forward` and `rp_filter` sysctls and adds an IP masquerade rule. If you look at vprox, we also do this but build a lot on top of it. https://github.com/modal-labs/vprox

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