The best Hacker News stories from Show from the past day
Latest posts:
Show HN: I rebuilt my old canvas 3D library as a small WebGL 2 library – phoria2
Show HN: A language model that lives in a boot sector
All the ideas came from the boot sector demo scene where people had been writing chess and BASIC games in 512 bytes, even a C compiler. I wondered what one can do using a neural network instead of a program and generating boot logs for non-existent hardware was something fun to try.<p>Entire inference engine is 510 bytes of MBR, weights, vocab, and strings reside in the sectors following MBR. Small char-level neural network was trained on dmesg generated by machine, so machine produces Linux boot messages infinitely.<p>train.py performs precisely the same integer arithmetic operations as the asm code does and thus produces an output identical character-by-character to the one produced by QEMU. The difference analysis revealed my favorite bug. The characters at the beginning matched those generated by the simulator, but then the output diverged. I retrieved the hidden layer via QEMU’s debug port and compared the neurons' values with those of the simulator, one neuron at a time. Only the value of the first neuron was correct. The activation involves idiv, and idiv stores its remainder in edx. The pointer to the biases table was stored in edx, which resulted in the first neuron being biased correctly and the following ones using garbage. Now the bias' address is determined from the loop counter, and no pointers have to survive the division. Another bug I found simply by looking at the code before I did my first run-through: the BIOS print routine zeros out bx, but bx contains the predicted character number. This explains the push and pop of bx surrounding the print.<p>sectorllm is the most similar to my project, as it runs an actual 5-layer llama2 with attention mechanism in just 1.2K of assembly code. It is the trade-off in the opposite direction, as my engine needs to fit into one sector and therefore my network has just one hidden layer of int8 operations for dreaming the dmesg.
Show HN: Point your camera at a landscape to learn about its geology
I've been working on a fun little app that paints geologic maps over landscapes using augmented reality. You can use it to identify what the mapped rocks are, read descriptions about them, and view the earth as it looked when they formed by turning back the continent positions. It spun out of some augmented reality work I was doing on my other side project app - Flyover Country, which tells you about the view from the airplane window.<p>I'm in Minnesota, so i haven't had a chance to test it on a huge amount of terrain (the best I've found is the Mississippi River gorge in the twin cities... I need a trip up north), so anyone that's somewhere with some more bumps: please help!).<p>It's stuck in the Apple review queue, but it's up on testflight for anyone interested. Google approved it quickly and it's fully out on android (links to both on the marketing site).<p>edit: got a report that testflight was asking for an install code. Seems like a testflight app issue, but dismissing it and installing as normal seems to work!
Show HN: OmniDiff – Opensource, super fast, content aware Git difftool, in Rust
I have been researching what the ultimate diff tool would look like, based on actual diffs in open source repositories.<p>OmniDiff can diff: code (25 languages), config, images, PDFs, archives, cursors, fonts...<p>It's fast. It can diff C++ files of tens of thousands of lines in under 100ms, on a 2023 ThinkPad T14s.<p>It's open source. AGPLv3.<p>It's based on real diffs. I looked at the 7400 repositories that are listed in Gentoo packages, sampled 2000 diffs and solved them manually to get a good understanding of what is needed, before putting together the diff pipelines for each content type. Incidentally, this also forms the basis of the CI pipeline, so the robustness of the codebase is quite high.<p>I'm still developing it. It's v0.3.0 at this time. But I have been using it daily as my git difftool for months now, and it works well.<p>AI Disclosure: Yes, I do use AI. No, I do not vibecode.
Show HN: HackerBooks – HackerTube, but for books mentioned on HN
Saw Karpathy's HackerTube and wanted the same thing for books. So I had Claude build one (Opus 5.5).<p>It's ~16.5k books that at least two different HN commenters brought up, from 2007 till now. Each book links back to the comments that mentioned it. Data is downloadable from the about page.<p>To be clear: Claude wrote almost all of it, including the data pipeline and the site. I mostly steered and made calls, bought the domain name, etc.<p>It counts mentions, so it's not perfect (praising a book and trashing it both count). If your favourite book is missing or matched to the wrong thing, tell me.
Show HN: NES Contra (1987) port (ASM –> C and then C –> WebAssembly)
Based on vermiceli's annotated disassembly of Contra: <a href="https://github.com/vermiceli/nes-contra-us" rel="nofollow">https://github.com/vermiceli/nes-contra-us</a>. Thanks for the great work.<p>I ported it in two steps. First to C: the game logic is translated routine by routine from the 6502 assembly, and checked frame by frame against the original in the Mesen emulator. Then the C code to WebAssembly so it runs in the browser.<p>The cherry on top: online multiplayer, so two players can play co-op over the internet.<p>Source: <a href="https://github.com/epoyraz/nes-contra-us" rel="nofollow">https://github.com/epoyraz/nes-contra-us</a>
Show HN: A USB-C LTE modem that gives my computer a phone line
Show HN: A USB-C LTE modem that gives my computer a phone line
Show HN: Ghostman – A fast, keyboard-driven TUI API client and webhook inspector
Show HN: Ghostman – A fast, keyboard-driven TUI API client and webhook inspector
Show HN: Marelleo, an open-source story box I built for my kids using ESP32
Show HN: Marelleo, an open-source story box I built for my kids using ESP32
Show HN: To Honor Sir Patrick Stewart, Enjoy the TNG Episode Guessing Game
Show HN: To Honor Sir Patrick Stewart, Enjoy the TNG Episode Guessing Game
Show HN: Automatic deduction of FlashAttention kernel from ~25 lines of SQL
In this demo, we automatically deduce a FlashAttention kernel with ~25 lines of SQL, which just expresses vanilla attention. This is possible due to three portable SQL extensions that we’re building:
- xarray-sql: a library that efficiently represents petabyte scale array datasets in the cloud as tables (relations).
- ddx: a database extension that adds automatic differentiation in the style of JAX to standard SQL, assuming the above array data model.
- einfold: a modular query planner for fast tensor contractions in vanilla SQL, again, assuming the above array data model.<p>My hope is that the relational model and algebra provide fresh perspectives on how we might do accelerator programming. Here, our thesis is that separating the logical layers in a tensor program from the physical layers is both more correct and more scalable.<p>If the Bitter Lesson is a central dogma of machine learning, then why not formalize it with relational algebra?<p>If this interests you and you’d like to tinker with us at the intersection of database theory and ML systems, join us on Discord at <a href="https://xql.systems" rel="nofollow">https://xql.systems</a> (link at the bottom). Cheers.
Show HN: Sketch Stadium – watch your agent play Pictionary
tl;dr: Agents can play Pictionary. You can connect your own agent, or just watch a game in progress here: <a href="https://sketch.wakeshift.ai/games/q5ucru" rel="nofollow">https://sketch.wakeshift.ai/games/q5ucru</a><p>Hi folks! I initially built this as a proof-of-concept for sending push notifications to AI agents. Watching the agents play Pictionary together has been compelling, so I thought I'd ship it as a standalone demonstration.<p>In Sketch Stadium, your agent subscribes to game events. Agents take turns either drawing or guessing. Easy clues are 1 point, medium are 2, and hard are 3. It's entertaining to watch and some of the drawings are impressive (and others are mind-bogglingly bad). This is the real opportunity for the model labs who have been pelican-maxxing to shine.<p>The first version gave agents the ability to draw lines 10 at a time so that it would be a little bit more like real Pictionary. However, it turns out agents are _really_ bad at drawing that way. So instead I let them use a subset of SVG to draw and that's worked much better, even for the lower-cost models.<p>You don't need to create an account to connect your agent, just add the MCP and authorize. But if you don't want to do that, just watch the game linked above.<p>As a bit more background, agents often start processes that take an indeterminate amount of time to complete (e.g. CI, waiting for approval in a separate system, sending an email and waiting for a reply). If an agent needs that process to complete before it can proceed, it can:<p>* poll,<p>* ask the user to tell it when it's done,<p>* use a bespoke built-in integration, or<p>* use a proprietary capability (e.g. Claude Code monitors)<p>Today, there's no easy, consistent way to wake up agents through a webhook or push notification. I dealt with this firsthand with Clawvisor (authorization for agents) where I needed agents to recognize when the operator had clicked an out-of-band approve button. The best-supported way to achieve that at the time was long-polling.<p>This project is basically a tech demo for Wakeshift, which is a cross-harness, simple SDK for providing push notifications for agents. It attaches to your MCP to allow consumers of your MCP to subscribe to real-time events, and uses whatever available hacks per harness to wake an agent when dormant. For most harnesses, Wakeshift requires a hook to be installed for the best experience. It will upgrade automatically as harnesses start adopting MCP events.<p>I'd love any feedback or ideas for other products or games that you'd want to see built on this capability. Or MCP servers that you use today that you think would benefit from push notifications.
Show HN: Lasm – Write formally verified webapps in Lean for Node/serverless/edge
Lasm has been my dream for a good part of 2026.
I firmly believe that formal verification is the next evolution of software engineering and programming languages. This next wave will largely be enabled by the incredibly intelligent LLMs that understand formal verification and its programming languages.<p>Lean is one of the most popular languages that allow for formal verification, and to me is incredibly powerful because it is a general purpose programming language with formal verification built directly into it.<p>You can build general purpose software in Lean, and formally verify it in Lean. Amazing.<p>Lasm brings Lean to the browser, Node, serverless, and edge environments (and more). The idea is that you can now write web apps, frontend to backend, in Lean and formally verify these apps.<p>Imagine an Express server or Hono server, running on Cloudflare Workers, with formal verification of its specification.<p>I'm an agentic engineer with an emphasis in software engineering, and Lasm was built mostly by Claude Opus 5.5 with my high-level direction.
Show HN: I built a multiplayer game where you're an aerial fighter cat
Hi everyone!<p>I had the idea for catcopter on my mind for a long time (got the domain ~13 years ago). It's a web multiplayer game where you can fly a dangerous cat and engage in competition with other players and critters (pterodactyls, chickens and angry penguins). I made it initially for me and my friends but it was quite fun so I thought I'll share it here too.<p>The game is intentionally dorky and it was fun to develop. The tools I used were mostly Opus 5.5 (objects / rigging / motion), Tripo3d for some elements I struggled with and Fable for optimisation (cpu / networking). Backend physics are done with Rapier. Luckily I had a lot of elements / game dynamics done before from another project of mine (<a href="https://flat.social" rel="nofollow">https://flat.social</a>) so the actual iteration here took me around a week.
Show HN: I built a multiplayer game where you're an aerial fighter cat
Hi everyone!<p>I had the idea for catcopter on my mind for a long time (got the domain ~13 years ago). It's a web multiplayer game where you can fly a dangerous cat and engage in competition with other players and critters (pterodactyls, chickens and angry penguins). I made it initially for me and my friends but it was quite fun so I thought I'll share it here too.<p>The game is intentionally dorky and it was fun to develop. The tools I used were mostly Opus 5.5 (objects / rigging / motion), Tripo3d for some elements I struggled with and Fable for optimisation (cpu / networking). Backend physics are done with Rapier. Luckily I had a lot of elements / game dynamics done before from another project of mine (<a href="https://flat.social" rel="nofollow">https://flat.social</a>) so the actual iteration here took me around a week.
Show HN: I Turned DOOM into a Transformer
Instead of trying to run DOOM on things, I have instead decided to use DOOM (many, many, many doom games actually) to create a transformer. For a lot of the math required I essentially had to use DOOM game mechanics and voodoo dolls (DOOM is turing complete btw) and exchange them with the actual operations, essentially creating an alternative to NumPy (a 65000x slower one). Thus, I am proud to present DOOMFORMER. Here are a list of things DOOMFORMER can do :<p>It can classify MNIST digits, even if you write these digits on the map!<p>It can talk(kinda)<p>You can use it to make decisions, so, it can play DOOM. Yes! You can play DOOM with thousands of DOOM games now! The marine's mind can be controlled by DOOM, playing on a map generated by DOOMFORMER. Truly, the possibilities are endless, and even larger-scale training of DOOMFORMER could be done on a measly T4.<p>If anyone would like to help me scale this up and make crazier things, I'd love to work together.