The best Hacker News stories from Show from the past week
Latest posts:
Show HN: Diagram as code tool with draggable customizations
In the past I've used declarative diagram generation tools like Mermaid.js a lot for quickly drawing up things but for presentations or deliverables I find that I have to then move the generated diagrams over to a tool like Lucidchart which allows full control of the organization and customization.<p>Therefore I am now working on this to combine the benefits of both into just one tool which can do both functions.<p>The project is certainly in the early stages but if you find yourself making architecture diagrams I'd love to hear your thoughts on the idea or even a Github issue for a feature request!<p>One of the workflows I'm targeting is when an AI generates the first draft of the diagram (all the LLMs know .mmd syntax) and then the user can then customize it to their liking which I think can drastically speed up making complex diagrams!
Show HN: Tommy – Turn ESP32 devices into through-wall motion sensors
Hi HN! I would like to present my project called TOMMY, which turns ESP32 devices into motion sensors that work through walls and obstacles using Wi-Fi sensing.<p>TOMMY started as a project for my own use. I was frustrated with motion sensors that didn't detect stationary presence and left dead zones everywhere. Presence sensors existed but were expensive and needed one per room. I explored echo localization first, but microphones listening 24/7 felt too creepy. Then I discovered Wi-Fi sensing - a huge research topic but nothing production-ready yet. It ticked all the boxes: could theoretically detect stationary presence through breathing/micromovements and worked through walls and furniture so devices could be hidden away.<p>Two years and dozens of research papers later, TOMMY has evolved into software I'm honestly quite proud of. Although it doesn't have stationary presence detection yet (coming Q1 2026) it detects motion really well. It works as a Home Assistant Add-on or Docker container, supports a range of ESP32 devices, and can be flashed through the built-in tool or used alongside existing ESPHome setups.<p>I released the first version a couple of months ago on Home Assistant's subreddit and got a lot of interest and positive feedback. More than 200 people joined the Discord community and almost 2,000 downloaded it.<p>Right now TOMMY is in beta, which is completely free for everyone to use. I'm also offering free lifetime licenses to every beta user who joins the Discord channel.<p>You can read more about the project on <a href="https://www.tommysense.com" rel="nofollow">https://www.tommysense.com</a>. Please join the Discord channel if you are interested in the project.<p>A note on open source: There's been a lot of interest in having TOMMY as an open source project, which I fully understand. I'm reluctant to open source before reaching sustainability, as I'd love to work on this full time. However, privacy is verifiable - it's 100% local with no data collection (easily confirmed via packet sniffing or network isolation). Happy to help anyone verify this.
Show HN: Tommy – Turn ESP32 devices into through-wall motion sensors
Hi HN! I would like to present my project called TOMMY, which turns ESP32 devices into motion sensors that work through walls and obstacles using Wi-Fi sensing.<p>TOMMY started as a project for my own use. I was frustrated with motion sensors that didn't detect stationary presence and left dead zones everywhere. Presence sensors existed but were expensive and needed one per room. I explored echo localization first, but microphones listening 24/7 felt too creepy. Then I discovered Wi-Fi sensing - a huge research topic but nothing production-ready yet. It ticked all the boxes: could theoretically detect stationary presence through breathing/micromovements and worked through walls and furniture so devices could be hidden away.<p>Two years and dozens of research papers later, TOMMY has evolved into software I'm honestly quite proud of. Although it doesn't have stationary presence detection yet (coming Q1 2026) it detects motion really well. It works as a Home Assistant Add-on or Docker container, supports a range of ESP32 devices, and can be flashed through the built-in tool or used alongside existing ESPHome setups.<p>I released the first version a couple of months ago on Home Assistant's subreddit and got a lot of interest and positive feedback. More than 200 people joined the Discord community and almost 2,000 downloaded it.<p>Right now TOMMY is in beta, which is completely free for everyone to use. I'm also offering free lifetime licenses to every beta user who joins the Discord channel.<p>You can read more about the project on <a href="https://www.tommysense.com" rel="nofollow">https://www.tommysense.com</a>. Please join the Discord channel if you are interested in the project.<p>A note on open source: There's been a lot of interest in having TOMMY as an open source project, which I fully understand. I'm reluctant to open source before reaching sustainability, as I'd love to work on this full time. However, privacy is verifiable - it's 100% local with no data collection (easily confirmed via packet sniffing or network isolation). Happy to help anyone verify this.
Show HN: Play abstract strategy board games online with friends or against bots
Thought I would post in celebration of 1 year of my website being online. I've been working on it on and off and currently the website allows users to play Hex, Tumbleweed, Amazons, and Connect 6 against friends or against practice bots. I've been a long time player of some of these games and I felt for a long time that the world could use a few more popular abstract strategy games compared to Chess or Go.<p>If you try it, let me know what you think. I'm always looking for new games or new features to add :)
Show HN: I built a tech news aggregator that works the way my brain does
An honest to god, non-algorithmic reverse chrono list of tech news that passes my signal-to-noise tests, updated hourly.<p>A lightweight a page design as I've been able to keep; simple, clean, fast. No commercial features or aspirations - this is a passion project, something I've been fooling around with on and off for decades.<p>There's a "Top" view too with an LLM edited front page & summary, and categorized views for a large number of topics - see the Directory. A few more buried features to explore, but the fundamental use case is pop in, scan, exit - fast and concise.<p>Your feedback would be appreciated!
Show HN: Cadence – A guitar theory app
Hello HN, I just released this music theory and ear training mobile app for guitar which I've been working on for a bit more than a year on the side.<p>The idea was to make something for the eternally "intermediate" guitarist (myself included). There are a lot of beginner apps which rely on learning songs, toolkits which give you a bunch of stuff with no explanation but not many in-between apps to actually learn and practice more generic and somewhat advanced stuff.<p>The app contains short lessons, recaps and most importantly challenges (visual, audio and pure theory) along with a very complete library.<p>The challenges are made for practicing, they will get increasingly harder and getting to the max score is supposed to be quite hard. The idea being that you have to repeat them regularly until your brain has integrated the info and it flows naturally rather than being a one time quick dopamine shot. This is partly inspired by how language learning apps work.<p>It has no ads, a lifetime purchase option and you can use it without an account if you don't care about multi-device sync or backing up your progress.<p>Android: <a href="https://play.google.com/store/apps/details?id=com.apizon.cadence.android">https://play.google.com/store/apps/details?id=com.apizon.cad...</a><p>iOS: <a href="https://apps.apple.com/us/app/cadence-guitar-theory/id6747011447?platform=iphone">https://apps.apple.com/us/app/cadence-guitar-theory/id674701...</a><p>(This is my second and last post about this sorry for spam. My first post a few weeks ago didn't get any views and posting on a saturday might not have helped...)
Show HN: I'm making a detective game built on Wikipedia
Hi HN!
Worked on this side project for a while and wanted to share it. It's free to play.
Show HN: I created a cross-platform GUI for the JJ VCS (Git compatible)
Personally, I think the JJ VCS (<a href="https://github.com/jj-vcs/jj" rel="nofollow">https://github.com/jj-vcs/jj</a>) hit a point some time in this past year where I find it hard to find a great reason to continue using git. Over the years I've cobbled together aliases and bash functions to try to improve my git workflow, but after using jj, which works with ~any git repo and integrates great with Github repos, all of the workflow issues I ran into with git are not only solved, but improved in ways I couldn't manage with simple scripts.<p>One example is the op log, which lets you go to any point in your repo's time and provides simple undo and redo commands when you want to back out of a merge, didn't mean to rebase, etc.<p>Because I have a pretty strong conviction that JJ is at this point a cleaner and more powerful version of git, my hopes are that it continues to grow. With that, it seemed a proper full-featured GUI was missing for the VCS. There's some plugins that add some integration into VS Code, and there's one in the works to get Intellij support working, but many of the constructs JJ provides in my opinion necessitate a grounds-up build of a GUI around how JJ works.<p>Right now, [name-redacted] is an MVP in an open beta. I did my best to support all of the core functionality one would need, though there's many nice-to-haves that I am going to add, like native merge support, native splitting, etc. Most of this will be based on feedback from the Beta.<p>I'm really grateful for the great community JJ has built, alongside the HN community itself in the countless VCS-based posts I've read over the years, and am hoping for lots of input here during Beta under real usage - the goal is to be a full-featured desktop GUI for the VCS, similar to many of the great products that are out there for git.
Show HN: Playwright Skill for Claude Code – Less context than playwright-MCP
I got tired of playwright-mcp eating through Claude's 200K token limit, so I built this using the new Claude Skills system. Built it with Claude Code itself.<p>Instead of sending accessibility tree snapshots on every action, Claude just writes Playwright code and runs it. You get back screenshots and console output. That's it.<p>314 lines of instructions vs a persistent MCP server. Full API docs only load if Claude needs them.<p>Same browser automation, way less overhead. Works as a Claude Code plugin or manual install.<p>Token limit issue: <a href="https://github.com/microsoft/playwright-mcp/issues/889" rel="nofollow">https://github.com/microsoft/playwright-mcp/issues/889</a><p>Claude Skills docs: <a href="https://docs.claude.com/en/docs/claude-code/skills" rel="nofollow">https://docs.claude.com/en/docs/claude-code/skills</a>
Show HN: Duck-UI – Browser-Based SQL IDE for DuckDB
I built Duck-UI, a web-based SQL editor that runs DuckDB entirely in your browser via WebAssembly. No backend required.<p>The Problem: Every time I needed to query csv, parquet, or even to play with SQL, I had to either:
(a) spin up a Jupyter notebook
(b) use the CLI
(c) upload to a hosted service.<p>Friction at every step (TOO MUCH to load a csv or even to test some sql (study)...<p>The Solution: DuckDB's WASM runtime lets us run SQL analysis client-side. Load CSV/JSON/Parquet files from disk or URL, write SQL, get results instantly. Data stays on your machine.
What It Does:<p>SQL editor with autocomplete & syntax highlighting
Import CSV, JSON, Parquet, Arrow (local or remote URLs)
Query history, keyboard shortcuts, theme toggle
Persistent storage via OPFS (data survives browser refresh)
Optional: Connect to external DuckDB servers
One-liner Docker deployment or Node 20+ dev server<p>Technical Details:<p>DuckDB compiled to WASM; query execution in-browser
OPFS-backed persistence
Apache 2.0 licensed
Runs on Chrome 88+, Firefox 79+, Safari 14+<p>Use Cases:<p>Learning SQL without setting up databases
Ad-hoc data exploration (CSV → SQL in seconds)
Quick prototyping before shipping to production
Privacy-conscious workflows (no data leaves your browser)<p>GitHub: <a href="https://github.com/ibero-data/duck-ui" rel="nofollow">https://github.com/ibero-data/duck-ui</a>
Live Demo: <a href="https://demo.duckui.com" rel="nofollow">https://demo.duckui.com</a>
Quick Start: docker run -p 5522:5522 ghcr.io/ibero-data/duck-ui:latest<p>Would love feedback on:
(1) Use cases I'm missing
(2) Performance bottlenecks you hit
(3) Features that would make this your default SQL scratchpad.
Show HN: Duck-UI – Browser-Based SQL IDE for DuckDB
I built Duck-UI, a web-based SQL editor that runs DuckDB entirely in your browser via WebAssembly. No backend required.<p>The Problem: Every time I needed to query csv, parquet, or even to play with SQL, I had to either:
(a) spin up a Jupyter notebook
(b) use the CLI
(c) upload to a hosted service.<p>Friction at every step (TOO MUCH to load a csv or even to test some sql (study)...<p>The Solution: DuckDB's WASM runtime lets us run SQL analysis client-side. Load CSV/JSON/Parquet files from disk or URL, write SQL, get results instantly. Data stays on your machine.
What It Does:<p>SQL editor with autocomplete & syntax highlighting
Import CSV, JSON, Parquet, Arrow (local or remote URLs)
Query history, keyboard shortcuts, theme toggle
Persistent storage via OPFS (data survives browser refresh)
Optional: Connect to external DuckDB servers
One-liner Docker deployment or Node 20+ dev server<p>Technical Details:<p>DuckDB compiled to WASM; query execution in-browser
OPFS-backed persistence
Apache 2.0 licensed
Runs on Chrome 88+, Firefox 79+, Safari 14+<p>Use Cases:<p>Learning SQL without setting up databases
Ad-hoc data exploration (CSV → SQL in seconds)
Quick prototyping before shipping to production
Privacy-conscious workflows (no data leaves your browser)<p>GitHub: <a href="https://github.com/ibero-data/duck-ui" rel="nofollow">https://github.com/ibero-data/duck-ui</a>
Live Demo: <a href="https://demo.duckui.com" rel="nofollow">https://demo.duckui.com</a>
Quick Start: docker run -p 5522:5522 ghcr.io/ibero-data/duck-ui:latest<p>Would love feedback on:
(1) Use cases I'm missing
(2) Performance bottlenecks you hit
(3) Features that would make this your default SQL scratchpad.
Show HN: Firm, a text-based work management system
Show HN: Scriber Pro – Offline AI transcription for macOS
Hey HN! Built this because I was tired of waiting hours for transcription
services and didn't want to upload sensitive recordings to the cloud.<p><pre><code> Real metrics from my M1 Max: 4.5hr video file transcribed in 3 minutes 32
seconds. Works completely offline.
First 5 HN users who click the button on the page get it free. Literally promo code straight to the app sore
Key differences vs Rev/Otter:
- No 2-hour file limits (handles any length)
- Timecodes stay accurate on long files (no drift from chunking)
- Supports MP3, WAV, MP4, MOV, M4A, FLAC
- Exports to SRT, VTT, JSON, PDF, DOCX, CSV, Markdown
Built for macOS. Happy to answer questions!</code></pre>
Show HN: Halloy – Modern IRC client
I started working on Halloy back in 2022, with the goal of giving something back to the community I’ve been a part of for the past two decades. I wanted to create a modern, multi-platform IRC client written in Rust.<p>Three years later, I’ve made new friends who have become core contributors, and there are now over 200 people idling in our #halloy channel on Libera.<p>My hope is that this client will outlive me and that IRC will live on.
Show HN: Baby's first international landline
Hi HN,<p>As a weekend project, I hacked together a physical phone, a Raspberry Pi running Asterisk and Twilio, to let toddlers safely make international calls.<p>I’ve documented the setup in this write-up and published the code + Ansible playbooks on GitHub so others can replicate it.<p>I built this so kids of expats can easily stay in touch with family on other continents.<p>Would love feedback from anyone who’s worked on something similar or tries building this themselves!<p>writeup: <a href="https://wip.tf/posts/telefonefix-building-babys-first-international-landline/" rel="nofollow">https://wip.tf/posts/telefonefix-building-babys-first-intern...</a>
github repos:
- <a href="https://github.com/nbr23/ansible-role-telefonefix" rel="nofollow">https://github.com/nbr23/ansible-role-telefonefix</a>
- <a href="https://github.com/nbr23/allo-wed" rel="nofollow">https://github.com/nbr23/allo-wed</a>
Show HN: AI toy I worked on is in stores
Alt link: <a href="https://mrchristmas.com/products/santas-magical-telephone" rel="nofollow">https://mrchristmas.com/products/santas-magical-telephone</a><p>Video demo: <a href="https://www.youtube.com/watch?v=0z7QJxZWFQg" rel="nofollow">https://www.youtube.com/watch?v=0z7QJxZWFQg</a><p>The first time I talked with AI santa and it responded with a joke I was HOOKED. The fun/nonsense doesn't click until you try it yourself. What's even more exciting is you can build it yourself:<p>libpeer: <a href="https://github.com/sepfy/libpeer" rel="nofollow">https://github.com/sepfy/libpeer</a><p>pion: <a href="https://github.com/pion/webrtc" rel="nofollow">https://github.com/pion/webrtc</a><p>Then go do all your fun logic in your Pion server. Connect to any Voice AI provider, or roll your own via Open Source. Anything is possible.<p>If you have questions or hit any roadblocks I would love to help you. I have lots of hardware snippets on my GitHub: <a href="https://github.com/sean-der" rel="nofollow">https://github.com/sean-der</a>.
Show HN: SQLite Online – 11 years of solo development, 11K daily users
Show HN: I made an esoteric programming language that's read like a spellbook
i made an esoteric programming language which i call spellscript.
every program is a "spell" written in a "grimoire," and you have to use keywords like summon, enchant, inscribe, and conjure.<p>it's literally read like a spellbook because the syntax consists of all natural language, and newlines are optional. your code can now be an essay, like everybody wants!<p>for example, if you want to print something, you'd write:
`begin the grimoire. inscribe whispers of "hello, world!". close the grimoire.`<p>it has variables, dynamic typing, arrays, functions, conditionals, loops, string manipulation, array manipulation, type conversion, and user input, among other (listed in the docs!)<p>but why? i wanted to see how far you could push natural language syntax while still being parseable. most esolangs are intentionally obtuse (BF, Malbolge), but i wanted something that's weird but readable, like you're reading instructions from a spellbook, which makes it incredibly easy to read and understand. like an anti-esolang? hmm...<p>github: <a href="https://github.com/sirbread/spellscript" rel="nofollow">https://github.com/sirbread/spellscript</a><p>docs: <a href="https://github.com/sirbread/spellscript/blob/main/resources/documentation.md" rel="nofollow">https://github.com/sirbread/spellscript/blob/main/resources/...</a>
Show HN: Rift – A tiling window manager for macOS
Show HN: Rift – A tiling window manager for macOS