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Show HN: Jax-JS, array library in JavaScript targeting WebGPU

Show HN: Mantic.sh – A structural code search engine for AI agents

Author here! Some context: I published this 48 hours ago and it was auto-listed on MCPMarket (the MCP tools directory). Got 700+ organic downloads with zero marketing—developers were actively searching for exactly this solution.<p>The "Git Accelerator" optimization story:<p>Initially used a file walker that took 6.6s on Chromium. Profiling showed 90% was filesystem I/O. The fix: git ls-files returns 480k paths in ~200ms. Added smart heuristics for untracked files (only scan dirs <50k files), bringing total to 0.46s.<p>Why this matters: Agents can't wait 10 seconds for search. Sub-500ms makes it feel instant, changing how they explore codebases.<p>Installation:<p><pre><code> Cursor: npx mantic.sh@latest VS Code: npx mantic.sh@latest CLI: npm i -g mantic.sh </code></pre> Limitations: Mantic is optimized for precise queries ("find stripe webhook") where structure matters. For fuzzy exploratory search, traditional embeddings may still be better. Curious if HN has ideas for hybrid approaches.<p>Happy to answer questions!

Show HN: 48-digit prime numbers every git commit

Show HN: I replaced Beads with a faster, simpler Markdown-based task tracker

I've been running long duration coding agents with Claude Code for about 6 months now. Steve Yegge released Beads back in October and I found that giving Claude tools for proper task tracking was a massive unlock. But Beads grew massively in a short time and every release made it slower and more frustrating to use. I started battling it several times a week as its background daemon took to syncing the wrong things at the wrong times.<p>Over the holidays I finally ripped it out and wrote ticket as a replacement. It keeps the core concept I actually cared about (graph-based task dependencies) but drops everything else.<p>ticket a single file bash script built on coreutils managing flat files. You don't need to index everything with SQLite when you have awk. It's just a small plumbing utility that gets out of your way so you can get to work.<p>Would love feedback on gaps. I built this for my own agent workflows so there are probably use cases I haven't thought about.

Show HN: Prism.Tools – Free and privacy-focused developer utilities

Hi HN, I'm Barry and I've built Prism.Tools (<a href="https://blgardner.github.io/prism.tools/" rel="nofollow">https://blgardner.github.io/prism.tools/</a>) – a collection of client-side developer utilities that respect your privacy.<p>Many of these tools were used way back in the days when I ran a BBS and started my communities first ISP, serving three local communities with Dial-Up Internet, Web Hosting etc. The tools have been refined to reflect the changes in tech since then and designed for the Novice and Pro alike. As I locate more tools others may find useful I will refine and add them to the collection. Use them, Share them, or not. They will be here if you need them...<p>40+ dev tools (JSON formatters, regex tester, base64 encoder, Git command helper, etc.) that run entirely in your browser. Zero tracking, zero analytics, zero data collection – everything processes locally. Self-contained HTML files with no build process or frameworks.<p>I realized I had a lot of tools/utilities I've built over the years for my own use. I lothe having to 'sign-up' just to access/use simple utilities that I can create myself. I've refined them and put them in one safe place so I could easily access them if/when needed. I decided to make them available via Github Pages for anyone that may find them useful. Prism.Tools is the result.<p>Each tool is a standalone HTML file with embedded CSS and JavaScript. No frameworks, no npm packages, no build steps – just open the file and it works.<p>The entire toolset:<p>- 100% client-side processing – your data never leaves your browser.<p>- No external dependencies except for specific libraries from cdnjs.cloudflare.com (marked.js for markdown, exifr for image metadata, etc.)<p>- Consistent dark UI – every tool follows the same design language for familiarity.<p>- Vanilla JS where possible – only reaching for Public CDN Resources when necessary.<p>The constraint of "single HTML file" was intentional. It forces simplicity and ensures tools remain maintainable. It also means users can inspect, modify, or self-host any tool trivially.<p>These tools have helped me with debugging production issues, Quick formatting tasks, learning Git commands (the Git command helper has been particularly helpful)<p>Just visit <a href="https://blgardner.github.io/prism.tools/" rel="nofollow">https://blgardner.github.io/prism.tools/</a> and try any tool. No signup, no install.<p>What tools are missing that you find yourself needing? Any performance issues with specific tools? UI/UX friction points?<p>All tools follow the same privacy-first philosophy... Your data stays in your browser. No accounts, no tracking, no servers processing your information. The project is also a demonstration that you don't always need React, Vue, or complex build pipelines – sometimes vanilla JavaScript in a single HTML file is exactly the right tool for the job.<p>Vanilla JavaScript (ES6+) CSS3 with CSS Grid Minimal external libraries: marked.js, exifr, highlight.js, sql-formatter (all from CDN) No frameworks, no bundlers, no npm Hosted on Github Pages<p>Happy to answer questions about the technical implementation, design decisions, or specific tools!<p>All tools are inspectable – just view source on any page to see exactly how they work!

Show HN: Server-rendered multiplayer games with Lua (no client code)

Hey folks — here’s a small experiment I hacked together over the weekend:<p><a href="https://cleoselene.com/" rel="nofollow">https://cleoselene.com/</a><p>In short, it’s a way to build multiplayer games with no client-side game logic. Everything is rendered on the server, and the game itself is written as simple Lua scripts.<p>I built this to explore a few gamedev ideas I’ve been thinking about while working on Abstra: - Writing multiplayer games as if they were single-player (no client/server complexity) - Streaming game primitives instead of pixels, which should be much lighter - Server-side rendering makes cheating basically impossible - Game secrets never leave the server<p>This isn’t meant to be a commercial project — it’s just for fun and experimentation for now.<p>If you want to try it out, grab a few friends and play here: <a href="https://cleoselene.com/astro-maze/" rel="nofollow">https://cleoselene.com/astro-maze/</a>

Show HN: Server-rendered multiplayer games with Lua (no client code)

Hey folks — here’s a small experiment I hacked together over the weekend:<p><a href="https://cleoselene.com/" rel="nofollow">https://cleoselene.com/</a><p>In short, it’s a way to build multiplayer games with no client-side game logic. Everything is rendered on the server, and the game itself is written as simple Lua scripts.<p>I built this to explore a few gamedev ideas I’ve been thinking about while working on Abstra: - Writing multiplayer games as if they were single-player (no client/server complexity) - Streaming game primitives instead of pixels, which should be much lighter - Server-side rendering makes cheating basically impossible - Game secrets never leave the server<p>This isn’t meant to be a commercial project — it’s just for fun and experimentation for now.<p>If you want to try it out, grab a few friends and play here: <a href="https://cleoselene.com/astro-maze/" rel="nofollow">https://cleoselene.com/astro-maze/</a>

Show HN: Circuit Artist – Circuit simulator with propagation animation, rewind

Hello,<p>Circuit Artist is a game about drawing digital circuits as pixel art — like MS Paint, but pixels are wires and little triangles are NANDs. Hit play and the simulation runs in real time. It's fully white-box: every wire's state is visible.<p>I launched it last year with a unit-delay simulation that ran until convergence on each update. It worked, but I realized it had some fundamental problems:<p>(i) It hid what was actually happening. Players couldn't tell the difference between a ripple carry adder and a look-ahead adder — everything just resolved instantly.<p>(ii) Design bugs became "game bugs." When players had non-converging wires (like A = not(A)), the game couldn't explain why or where the error was.<p>(iii) Layout didn't matter. A NAND on one side of the map would instantly propagate to the opposite side, making spatial decisions meaningless. Unit delay probably works better for schematic-based simulators like Logisim, not a layout-focused game like this.<p>(iv) Propagation visualization couldn't be added on top of the unit-delay engine — there was no notion of direction or distance.<p>So I rebuilt the engine with variable-delay event-based simulation using an adaptation of Elmore delay. The delay for each wire depends on distance and fanout — longer wires are slower, higher fanout adds delay, branching wires are faster.<p>For the implementation: I compute Elmore delay over wire trees. Each pixel has resistance and capacitance, with NAND inputs as nodes to account for fanout. For non-tree wire graphs, I build a Dijkstra-based spanning tree (driver as root) and interpolate for edges outside the tree. I calculate the delay for each node and project it back to the image so every pixel has a distance.<p>This lets me animate propagation with a glow effect during simulation. The shader knows when each wire was triggered, the current time, and the Elmore distance of each pixel, so it resolves state per-pixel in real time.<p>On top of that:<p>- Time rewind: the simulation is now delta-based, so players can freeze and scrub backwards to debug. Super useful for cyclic circuits.<p>- Layers: since timing matters now, I added up to 3 layers. NANDs only go on the bottom layer, upper layers propagate faster (lower capacitance). Lets you route wires above dense NAND areas.<p>The game has a campaign for learning from scratch, though it's still incomplete and in progress. I'm working toward Steam Workshop support so people can create their own campaigns to teach different concepts or cover more advanced topics.<p>GitHub (full source): <a href="https://github.com/lets-all-be-stupid-forever/circuit-artist" rel="nofollow">https://github.com/lets-all-be-stupid-forever/circuit-artist</a><p>Steam: <a href="https://store.steampowered.com/app/3139580/Circuit_Artist/" rel="nofollow">https://store.steampowered.com/app/3139580/Circuit_Artist/</a>

Show HN: Circuit Artist – Circuit simulator with propagation animation, rewind

Hello,<p>Circuit Artist is a game about drawing digital circuits as pixel art — like MS Paint, but pixels are wires and little triangles are NANDs. Hit play and the simulation runs in real time. It's fully white-box: every wire's state is visible.<p>I launched it last year with a unit-delay simulation that ran until convergence on each update. It worked, but I realized it had some fundamental problems:<p>(i) It hid what was actually happening. Players couldn't tell the difference between a ripple carry adder and a look-ahead adder — everything just resolved instantly.<p>(ii) Design bugs became "game bugs." When players had non-converging wires (like A = not(A)), the game couldn't explain why or where the error was.<p>(iii) Layout didn't matter. A NAND on one side of the map would instantly propagate to the opposite side, making spatial decisions meaningless. Unit delay probably works better for schematic-based simulators like Logisim, not a layout-focused game like this.<p>(iv) Propagation visualization couldn't be added on top of the unit-delay engine — there was no notion of direction or distance.<p>So I rebuilt the engine with variable-delay event-based simulation using an adaptation of Elmore delay. The delay for each wire depends on distance and fanout — longer wires are slower, higher fanout adds delay, branching wires are faster.<p>For the implementation: I compute Elmore delay over wire trees. Each pixel has resistance and capacitance, with NAND inputs as nodes to account for fanout. For non-tree wire graphs, I build a Dijkstra-based spanning tree (driver as root) and interpolate for edges outside the tree. I calculate the delay for each node and project it back to the image so every pixel has a distance.<p>This lets me animate propagation with a glow effect during simulation. The shader knows when each wire was triggered, the current time, and the Elmore distance of each pixel, so it resolves state per-pixel in real time.<p>On top of that:<p>- Time rewind: the simulation is now delta-based, so players can freeze and scrub backwards to debug. Super useful for cyclic circuits.<p>- Layers: since timing matters now, I added up to 3 layers. NANDs only go on the bottom layer, upper layers propagate faster (lower capacitance). Lets you route wires above dense NAND areas.<p>The game has a campaign for learning from scratch, though it's still incomplete and in progress. I'm working toward Steam Workshop support so people can create their own campaigns to teach different concepts or cover more advanced topics.<p>GitHub (full source): <a href="https://github.com/lets-all-be-stupid-forever/circuit-artist" rel="nofollow">https://github.com/lets-all-be-stupid-forever/circuit-artist</a><p>Steam: <a href="https://store.steampowered.com/app/3139580/Circuit_Artist/" rel="nofollow">https://store.steampowered.com/app/3139580/Circuit_Artist/</a>

Show HN: A simulator for engineers transitioning from IC to management

Hi HN,<p>I’m a former C++ dev turned Product Manager.<p>I’ve noticed many engineers struggle with the "politics" side of things when they become Leads. To help with this, I’m building a text-based simulator.<p>It is NOT an AI chatbot. It is a hand-crafted, branching narrative (logic tree) based on real experiences.<p>I just launched the first scenario: "The Backchannel VP."<p>The Setup: Your VP Engineering is bypassing you and giving tasks directly to your juniors, causing chaos.<p>Your Goal: Stop the backchanneling without getting fired.<p>It’s a short, specific puzzle. I’d love to know if you think the "Correct" path I designed matches your real-world experience, or if I’m off base.<p>Link: <a href="https://apmcommunication.com/scenario/backchannel-vp" rel="nofollow">https://apmcommunication.com/scenario/backchannel-vp</a>

Show HN: A simulator for engineers transitioning from IC to management

Hi HN,<p>I’m a former C++ dev turned Product Manager.<p>I’ve noticed many engineers struggle with the "politics" side of things when they become Leads. To help with this, I’m building a text-based simulator.<p>It is NOT an AI chatbot. It is a hand-crafted, branching narrative (logic tree) based on real experiences.<p>I just launched the first scenario: "The Backchannel VP."<p>The Setup: Your VP Engineering is bypassing you and giving tasks directly to your juniors, causing chaos.<p>Your Goal: Stop the backchanneling without getting fired.<p>It’s a short, specific puzzle. I’d love to know if you think the "Correct" path I designed matches your real-world experience, or if I’m off base.<p>Link: <a href="https://apmcommunication.com/scenario/backchannel-vp" rel="nofollow">https://apmcommunication.com/scenario/backchannel-vp</a>

Show HN: Tailsnitch – A security auditor for Tailscale

Show HN: Tailsnitch – A security auditor for Tailscale

Show HN: DoNotNotify – Log and intelligently block notifications on Android

Why - I got sick of apps abusing notifications on my Android phone. While the OS does give you the ability to switch off notifications based on channels, most apps either don't use it or abuse it intentionally. In my case, I live in a gated society that uses an app called MyGate to allow visitors, and the app intentionally pushes ads through the same channels since you cannot block them.<p>What - DoNotNotify is an app that logs all incoming notifications, and displays them grouped by app. It also captures the action behind the notification, which can be triggered from the app itself. From this log, you can create rules to whitelist/blacklist notifications from apps depending on their notification content. These filters can even be regex expressions, which allows for more complicated use-cases. The app ships with some pre-defined rules for popular apps like Facebook, Amazon, Instagram, Netflix, TikTok, Reddit etc.<p>Where - The website is at <a href="https://donotnotify.com/" rel="nofollow">https://donotnotify.com/</a>.<p>Would also like to call out that the app runs purely on your device, never communicates with anything on the Internet, and only requires notifications access to work. It is completely free, and there is no advertising or hidden gotchas.

Show HN: DoNotNotify – Log and intelligently block notifications on Android

Why - I got sick of apps abusing notifications on my Android phone. While the OS does give you the ability to switch off notifications based on channels, most apps either don't use it or abuse it intentionally. In my case, I live in a gated society that uses an app called MyGate to allow visitors, and the app intentionally pushes ads through the same channels since you cannot block them.<p>What - DoNotNotify is an app that logs all incoming notifications, and displays them grouped by app. It also captures the action behind the notification, which can be triggered from the app itself. From this log, you can create rules to whitelist/blacklist notifications from apps depending on their notification content. These filters can even be regex expressions, which allows for more complicated use-cases. The app ships with some pre-defined rules for popular apps like Facebook, Amazon, Instagram, Netflix, TikTok, Reddit etc.<p>Where - The website is at <a href="https://donotnotify.com/" rel="nofollow">https://donotnotify.com/</a>.<p>Would also like to call out that the app runs purely on your device, never communicates with anything on the Internet, and only requires notifications access to work. It is completely free, and there is no advertising or hidden gotchas.

Show HN: I built an international calling platform for the past 6 months

Show HN: Claude Reflect – Auto-turn Claude corrections into project config

Show HN: Claude Reflect – Auto-turn Claude corrections into project config

Show HN: Replacing my OS process scheduler with an LLM

Show HN: Replacing my OS process scheduler with an LLM