Show HN: KaraMagic – automatic karaoke video maker https://ift.tt/T09hcbi

Show HN: KaraMagic – automatic karaoke video maker Hi all, this is an early version of a side project of mine. Would love some feedback and comments. I like karaoke and I grew up with the Asian style karaoke with the music video behind and the karaoke lyrics at the bottom. Sometimes I want to do a song and there is no karaoke version video like that. A few years ago I came across ML models that cleanly separate the vocals and the instrumental music of a song. I thought of the idea to chain together ML models that can take an input music video file, extract the audio (ffmpeg), separate the tracks (ML), transcribe the lyrics (ML), burn the lyrics back with timing into the video (ffmpeg), and output a karaoke version of the video. This is an early version of the app, Mac only so far (since I use Mac, despite it being an electron app.. I do eventually want to make a Windows build), I've only let a few friends try it. Let me know what you think! https://karamagic.com/ March 10, 2026 at 11:58PM

Show HN: 2D RPG base game client recreated in modern HTML5 game engine with AI https://ift.tt/ia64W15

Show HN: 2D RPG base game client recreated in modern HTML5 game engine with AI When I was much younger, I used to play a Korean MMORPG called Helbreath, and I also hosted a bunch of private servers for it. I eventually moved on, but I always loved the game’s aesthetics, its 2D nature, and its atmosphere. That may just be nostalgia talking. The community maintained private server and client, which to my knowledge were based on leaked official files, were written in fairly archaic C++. If you’re interested in the original sources, I’ve included the main client and server files, Client.cpp and Server.cpp, in the reference folder. I always felt that if the project was rewritten in something more modern and better structured, a lot more could be done with it. But rewriting an MMORPG client and server from scratch is not exactly the kind of thing you do on a whim. That said, there was a guy who got pretty far with a C# rewrite and an XNA-based client, though that project is now also discontinued. Now that AI has become quite capable, I decided to see how far I could get by hooking up the original assets in a modern HTML5 game engine. I wanted HTML5 because I figured a nearly 30 year old 2D game should run just fine in a browser. I ended up choosing Phaser 3 for a few reasons. Mainly, it's 2D only, free, HTML5 first (JS/TS), and code-first, which mattered because I wanted good Cursor integration for AI assistance. Another thing I liked was its integration with React, which let me build the UI using browser technologies and render the UI at native resolution on top of the WebGL canvas, rather than building the UI inside the game engine itself, which runs at 1024x576 resolution. The original game ran at 640x480. After about 1.5 months of talking to AI on evenings and weekends, and roughly $200 worth of Cursor usage later, I finished hooking up the original assets in a modern game engine that seems to run just fine in a browser. By "base game client", I mean that it's not fully hooked up in terms of how the full (MMO)RPG should function, but it does include all the original assets and core mechanics needed to provide a solid foundation if you want to build your own 2D (MMO)RPG on top of it. Continuing to build with AI should also work just fine, since this is how I managed to get that far. The asset library is quite rich, if you ask me, but there is one caveat: these assets are not in the public domain. They are still the property of someone, or some entity, that inherited the IP from the original developer, which is no longer in business. You can read more about that on the GitHub page. https://ift.tt/Rc7WG8Z March 11, 2026 at 12:09AM

Show HN: Don't share code. Share the prompt https://ift.tt/B0ynCtb

Show HN: Don't share code. Share the prompt Hey HN, I'm Mario. I recently talked to a colleague about AI, agents and how software development will change in the future. We were wondering why we should even share code anymore when AI agents are already really good at implementing software, just through prompts. Why can't everyone get customized software with prompts? "Share the prompt, not the code." Well, I thought, great idea, let's do that. That's why I built Open Prompt Hub: https://ift.tt/QTiIR48 . Think GitHub just for prompts. The idea is simple: Users can upload prompts that can then be used by you and your AI tools to generate a script, app, or web service (or prime their agent for a certain task): Just past it into your agent or ide and watch it build for you. If the prompt does not 100% covers your usecase, fork it, tweak it, et voila: tailor-made software ready to use! The prompts are simple markdown files with a frontematter block for meta information. (The spec can be found here: https://ift.tt/nhzcuDr ) They versioned, have information on which AI models build it successfuly and have instructions on how the AI agent can test the resulting software. Users can mention with which models they have successfully or unsuccessfully executed a prompt (builds or fail). This helps in assessing whether a prompt provides reliable output or not. Want to create a open prompt file? Here is the prompt for it which will guide you through: https://ift.tt/wTCZ8Ql Security! Always a topic when dealing with AI and prompts? I've added several security checks that look at every prompt for injections and malicious behavior. Statistical analysis as well as two checks against LLMs for behaviour classification and prompt injection detection. It's an MVP for now. But all the mentioned features are already included. If this sounds good, let me know. Try a prompt, fork it, or tell me what you'd change in the spec or security scanner. I'm really curious about what would make you trust and reuse prompts. Or if you like the general idea... https://ift.tt/Emp3IsY March 10, 2026 at 10:59PM

Show HN: MindfulClaude – Guided breathing during Claude Code's thinking time https://ift.tt/eSuYk0X

Show HN: MindfulClaude – Guided breathing during Claude Code's thinking time Every time Claude Code thinks, you get 10-60s of idle time, usually spent on context switching or doomscrolling. I turned it into breathing exercises that keep you focused and improve your heart rate variability. Auto-launches a tmux pane using hooks when Claude starts working and disappears when it finishes. https://ift.tt/oFw4hO8 March 9, 2026 at 10:43PM

Show HN: Time as the 4th Dimension – What if it emerges from rotational motion? https://ift.tt/z5iWCLo

Show HN: Time as the 4th Dimension – What if it emerges from rotational motion? I've been developing a framework since 2022 that proposes time is not a static geometric axis (as in Einstein's relativity) but emerges dynamically from the rotational and orbital motion of 3D space. The core idea: each dimension emerges from the previous one by arranging infinite instances perpendicularly. A static 3D space can't do this to itself — but a rotating one can. That perpetual self-perpendicularity is time. From this we can derive the Lorentz factor, E=mc², and the Schwarzschild radius, and propose a testable prediction: intrinsic rotation should contribute independently to time dilation, measurable with atomic clocks. Essay (accessible): https://ift.tt/GC3zc7p... Paper (Zenodo): https://ift.tt/noxXcQN March 9, 2026 at 09:48PM

Show HN: I built a site where strangers leave kind voice notes for each other https://ift.tt/lXf7gxZ

Show HN: I built a site where strangers leave kind voice notes for each other https://ift.tt/DCdRpso March 9, 2026 at 02:12AM

Show HN: Lobster.js – Extended Markdown with layout blocks and footnotes https://ift.tt/2ExByvQ

Show HN: Lobster.js – Extended Markdown with layout blocks and footnotes Hi HN! I built lobster.js which is an extended Markdown parser that renders directly in the browser — no build tool, no framework, no configuration. The entire setup is a single script tag: It's particularly useful for GitHub Pages sites where you want Markdown-driven content without pulling in Jekyll or Hugo. --- What makes it different from marked.js or markdown-it: Standard parsers convert Markdown to HTML — that's it. lobster.js adds layout primitives to the Markdown syntax itself: - :::warp id defines a named content block; [~id] places it inside a silent table cell. This is how you build multi-column layouts entirely in Markdown, without touching HTML. - :::details Title renders a native

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collapsible block. - :::header / :::footer define semantic page regions. - Silent tables (~ | ... |) create borderless layout grids. - Cell merging: horizontal (\|) and vertical (\---) spans. - Image sizing: . --- CSS-first design: Every rendered element gets a predictable lbs-* class name (e.g. lbs-heading-1, lbs-table-silent). No default stylesheet is bundled — you bring your own CSS and have full control over appearance. --- The showcase site is itself built with lobster.js. The sidebar is nav.md, and each page is a separate Markdown file loaded dynamically via ?page= query parameters — no JS router, no framework. Markdown is the one format that humans and LLMs both write fluently. If you want a structured static site without a build pipeline, lobster.js lets that Markdown become a full web page — layout and all. GitHub: https://ift.tt/OxcK0wf Showcase: https://hacknock.github.io/lobsterjs-showcase/ https://ift.tt/OxcK0wf March 8, 2026 at 10:10PM