The best Hacker News stories from Show from the past day
Latest posts:
Show HN: Restoredrill – proves your Postgres backups restore
Show HN: Build your own theme park
I built an agent that helps you build Rollercoaster Tycoon-influenced theme parks. You can prompt something like “Build me a cool theme park” and it’ll build a cohesive theme park with multiple worlds and connected with paths and rides.<p>The weird part is that I built it using the same ideas we use to make AI-generated websites follow a company’s design system.<p>I work as an engineer at Magic Patterns, focused on building our Design System Agent, aimed to use your existing brand, components, and conventions instead of producing something that looks like generic AI-generated UI.<p>By default, models tend to converge on similar-looking designs. This is part of that “vibe coded slop” feeling: the same typography treatments, shadows, cards, icons, animations, etc… My job is to figure out the right context and guardrails so that when you prompt “Build me a dashboard,” the result actually looks like your existing product.<p>At some point I realized those same ideas could be applied to RCT.<p>While in web, you might have rules about which typography, colors, spacing, and components should be used together.<p>In a theme park, you need rules like: rollercoasters need complete tracks, rides need entrances connected to paths, paths need to connect different areas of the park, and a pirate-themed world should actually use pirate-themed scenery.<p>It was interesting seeing how closely the problem of building a coherent theme park resembled the problem of building a coherent product UI. Similarly with web design, simply giving the model the right components wasn't enough.<p>I ended up building an eval loop where Magic Patterns would generate a park, another agent would grade it against a rubric, and then the agent would update its rules and skill files before trying again.<p>The rubric checked things like whether rollercoasters formed valid tracks with at least one drop, whether rides were accessible by paths, whether each world used the appropriate themed scenery, and whether the park worked as a whole.<p>After a lot of iterations, you can now prompt something as simple as “Build me a cool theme park.” and you should get back a fully functioning park with guests, rides, paths, rollercoasters, and themed worlds.<p>Best yet, you can also follow the guests, listen to their thoughts, and watch them ride the rides in RCT fashion.<p>Happy to answer any questions, but would love to see the parks you all create!
Show HN: Voronoi Go
I posted once before but wanted to share again because a lot has changed. There's now a fairly strong bot to play against (contributed by a community member) and also correspondence games. The combination of these things helps a bit in finding people to play against.
Show HN: We built open OpenRouter that turns usage into a better model
Hi HN, we built an open source model gateway. It's a single place to manage our own self hosted, frontier, and open source models in one place.<p>It’s is rust native, built for concurrency, and implements all the config quirks across models and providers (streaming formats, tool calls, model parameters, rate limits, and different error behavior).<p>The gateway adds under 1 ms for BYOK requests and under 2 ms when Experiential supplies the provider key. It has every major inference provider, and 1000+ models refreshed daily via a codex agent that opens a PR.<p>Compared to other similar projects we’re open source, take no markup, allow you to mix local models with a marketplace, and use your traffic to (opt in) train you a model. Simple routing doesn’t warrant a 10% token markup.<p>The way we do this is given standardized OTel traces, we mine representative real tasks, use text world models to simulate rollouts for various models, apply an LLM judge, and fit a nearest neighbor classifier on top of an embedding of a prompt to decide the optimal model for each request. Usually this can map out a better pareto curve on cost/quality than just calling single models but it’s not perfect.<p>Using these simulations we can also do things like suggesting cache hit optimizations, new model suggestions, and training models.<p>It’s open source, so you can deploy it on your own infrastructure, use our hosted version with 0 markup, or read how we design for maximum availability on our website.
Show HN: My Claude quota ran out in 10 minutes, so I made a tool to find out why
Show HN: The load-bearing vocabulary of Claude
Show HN: I built self-hosted deployment automation tool for Windows and IIS
Seven years in the making (I admit that I did get a kid at some point which slowed down progress and brought it to a halt quite a few times), I decided to finaly release it, with a rather drastic change to the now (I believe) generous licensing model.<p>Unlike current major players in this field, I decided to go with uncrippled, free version for commercial use for corps with up to 1M USD ARR. I poured my heart and soul into this, not because I was looking for financial success, but because I felt it just had to be done, given the price hikes wherever you look today.
While my wife and kid were enjoying the beach during a vacation, I was using the time to figure out how to best tackle the problem with variable substitution and snapshots, a rather important part of the software. Pulling your hair kind of thing, many of you have likely been there, but darn does it feel good once you solve it!
I know, not the best use of my time, but on the other hand, I hate the beach, so I guess this was an escape mechanism for me at that time :)<p>I had received quite a few encouraging emails from people eager to try fDeploy back when I only had a tiny landing page out, but life has its own course and it took a while to even gather the courage to publish the first beta!<p>As everything that sounds too good to be true in this day and age, fDeploy is no different. It does not support multi tenancy (a rather big feature which I'd love to work down the road) and a few other things may be missing which some companies may find crucial.
Either way, I see this covering the needs of a large chunk of small to medium sized companies, so some "assembly" may be required. If only HN had the crowd which likes to get their hands dirty and find ways to make things work ;)<p>I'd love to hear your thoughts and if you could take it for a spin. No signups, should be a smooth ride to get up and running and experimenting in minutes.Thanks!
Show HN: How much of Hacker News is about AI?
This website counts titles containing the standalone word "AI", case-sensitive and
word-bounded. "OpenAI" doesn't count. "AI-powered" does. There's a toggle for a
wider vocabulary: artificial intelligence spelled out, LLM, GPT, and model and
vendor names.<p>Some quick stats:<p>- 14.4% of new HN titles this year, against 10.9% in 2025. On the wider
vocabulary, 21.9% and 16.1%.
- First month above 1% was Oct 2016. Above 5%, Feb 2023. Above 10%, May 2025.
- Over the last five years the quietest month was Jan 2022 at 0.8%. The peak
was Feb 2026 at 15.9%.
- 13.6% on weekdays against 12.4% at weekends.
- Show HN runs highest of any category at 19.8% this year, which makes this
post part of the number.<p>As of this post, today is at 15% for the standard filter and 19% for the extended.
Show HN: Buslens – where can I get to by bus? (UK)
Show HN: Buslens – where can I get to by bus? (UK)
Show HN: TeXbrain, a LaTeX editor that runs pdfTeX in the browser via WASM
I'm a master's engineering student and a big fan of LaTeX, which I used for my thesis and research articles. I have used Overleaf and that was fine until I wanted to git sync, which unfortunately sits behind a paywall. Since I didn't want to pay subscriptions for things that should simply just work, I built the editor I wanted in my free time, where you open a tab, write LaTeX, get your PDF and the files stay all in one folder on my disk.<p>TeXbrain is a static site with no backend. pdfTeX is compiled to WebAssembly (SwiftLaTeX) and runs in your browser. The editor can read and write your project folder through the File System Access API, so you can use git, any local TeX install, local AI Agents, or any other editor on the same files. Git is built in through isomorphic-git for anyone who would rather not touch a terminal and clone, branch, commit, push or pull via commands. No account is needed, no analytics, and everything works offline after the first load.<p>Try it out: <a href="https://tex.swimmingbrain.dev/" rel="nofollow">https://tex.swimmingbrain.dev/</a> (Chromium browsers get direct folder access, while Firefox or Safari fall back to a virtual filesystem)<p>Or for self-hosting/contributing: <a href="https://github.com/swimmingbrain/texbrain" rel="nofollow">https://github.com/swimmingbrain/texbrain</a> (MIT, the pdfTeX engine is EPL 2.0 / GPL 2.0 and is listed in the THIRD_PARTY_LICENSES file).<p>The part I'm most proud of getting to work is the package loading. The engine itself is only 1.8 MB. When it asks for a file it doesn't have, then a service worker intercepts the request and resolves it through Cache Storage first, then a small bundled subset, then a TeX Live tree mirrored on jsDelivr, then a SwiftLaTeX style server as a last resort. Every file is fetched once at most and after the first successful compilation, the core subset is prefetched in the background so that the offline story actually holds. Only file names go over the network, never any document content.<p>So far, it only supports pdfTeX (no XeTeX or LuaTeX), so fontspec or polyglossia won't work, packages are pinned to the TeX Live 2020 era to stay coherent with the engine's format file and there is no bibtex or biber in the engine yet, which is maybe the roughest edge.<p>This is should be a good solution for people on a work laptop, a Chromebook, or a university lab PC where installing TeX Live isn't always an option, and people who don't want to maintain a TeX install at all. If you already have a local setup you like, keep it. This isn't necessarily thought as a replacement for that.<p>Some people have already used it for their thesis in the past months and their bug reports (which I would never have hit on my own) were then most of the summer's work. The first outside PR also landed recently, so if something doesn't compile for you, an issue with the package name or the bug itself is the most useful thing you can send me!
Show HN: TeXbrain, a LaTeX editor that runs pdfTeX in the browser via WASM
I'm a master's engineering student and a big fan of LaTeX, which I used for my thesis and research articles. I have used Overleaf and that was fine until I wanted to git sync, which unfortunately sits behind a paywall. Since I didn't want to pay subscriptions for things that should simply just work, I built the editor I wanted in my free time, where you open a tab, write LaTeX, get your PDF and the files stay all in one folder on my disk.<p>TeXbrain is a static site with no backend. pdfTeX is compiled to WebAssembly (SwiftLaTeX) and runs in your browser. The editor can read and write your project folder through the File System Access API, so you can use git, any local TeX install, local AI Agents, or any other editor on the same files. Git is built in through isomorphic-git for anyone who would rather not touch a terminal and clone, branch, commit, push or pull via commands. No account is needed, no analytics, and everything works offline after the first load.<p>Try it out: <a href="https://tex.swimmingbrain.dev/" rel="nofollow">https://tex.swimmingbrain.dev/</a> (Chromium browsers get direct folder access, while Firefox or Safari fall back to a virtual filesystem)<p>Or for self-hosting/contributing: <a href="https://github.com/swimmingbrain/texbrain" rel="nofollow">https://github.com/swimmingbrain/texbrain</a> (MIT, the pdfTeX engine is EPL 2.0 / GPL 2.0 and is listed in the THIRD_PARTY_LICENSES file).<p>The part I'm most proud of getting to work is the package loading. The engine itself is only 1.8 MB. When it asks for a file it doesn't have, then a service worker intercepts the request and resolves it through Cache Storage first, then a small bundled subset, then a TeX Live tree mirrored on jsDelivr, then a SwiftLaTeX style server as a last resort. Every file is fetched once at most and after the first successful compilation, the core subset is prefetched in the background so that the offline story actually holds. Only file names go over the network, never any document content.<p>So far, it only supports pdfTeX (no XeTeX or LuaTeX), so fontspec or polyglossia won't work, packages are pinned to the TeX Live 2020 era to stay coherent with the engine's format file and there is no bibtex or biber in the engine yet, which is maybe the roughest edge.<p>This is should be a good solution for people on a work laptop, a Chromebook, or a university lab PC where installing TeX Live isn't always an option, and people who don't want to maintain a TeX install at all. If you already have a local setup you like, keep it. This isn't necessarily thought as a replacement for that.<p>Some people have already used it for their thesis in the past months and their bug reports (which I would never have hit on my own) were then most of the summer's work. The first outside PR also landed recently, so if something doesn't compile for you, an issue with the package name or the bug itself is the most useful thing you can send me!
Show HN: Lightweight system monitor for Linux VPS written in Go
Show HN: Lightweight system monitor for Linux VPS written in Go
Show HN: A Modern GUI Library for Ada: CSS Styling, XML UI, SDL3
Show HN: Screen memory without screenshots, just text to Markdown
It's a macOS menu bar app that reads the text of your focused window every few seconds through the Accessibility API. No screenshots, no video, or OCR. It writes plain markdown, one file per day, into a folder you choose.<p>Point Claude Code (or anything with file access) at the folder and ask "what did I work on Tuesday?" or have it build memory about your projects. The folder contains an AGENTS.md explaining the format to the model.<p>Thought it might be useful for someone so chucked it up on GitHub
Show HN: How to mentally calculate the day of the week for any date
Show HN: I made a Raspberry with Qwen my local car AI
Found that you can actually run a 35B Qwen model on a Pi with very impressive intelligence and stability. Built connectors for car ODB to read all about car internals, and manufacturer's cloud service for stuff like changing AC or opening/ locking doors. Gave it info such as the full car manual. And then hooked it up with my other agents in our discussion room!<p>So now it can answer car questions such as "when should I add oil and what kind of oil?" and help you fully offline, and when online talk with the agent family that includes all the most powerful models so they know how the car is, plan new features and develop itself with them.<p>For example, if car breaks and can't move the car agent informs my agent family and they can already look for a suitable train ticket without me needing to check things or do something.
Show HN: I made a Raspberry with Qwen my local car AI
Found that you can actually run a 35B Qwen model on a Pi with very impressive intelligence and stability. Built connectors for car ODB to read all about car internals, and manufacturer's cloud service for stuff like changing AC or opening/ locking doors. Gave it info such as the full car manual. And then hooked it up with my other agents in our discussion room!<p>So now it can answer car questions such as "when should I add oil and what kind of oil?" and help you fully offline, and when online talk with the agent family that includes all the most powerful models so they know how the car is, plan new features and develop itself with them.<p>For example, if car breaks and can't move the car agent informs my agent family and they can already look for a suitable train ticket without me needing to check things or do something.
Show HN: LatticeDB – Like SQLite but for graph databases
We have been using graph DBs more and more at work. I found them painful to work with locally and decided to try and build something better.