Show HN Daily Selection (2025-05-21)
- 90s.dev – Game maker that runs on the web
- A Tiling Window Manager for Windows, Written in Janet
- A Simple Server to Match Long/Lat to a TimeZone
- Juvio – UV Kernel for Jupyter
- Text to 3D simulation on a map (does history pretty well)
- Olelo Foil - NACA Airfoil Sim
- Astra – a new js2exe compiler
- Bricks – One Click Dashboards from Your Data Using AI
- I made IP-to-Geo location data library for developers
- JavaFactory – IntelliJ plugin to generate Java code
- A browser-based tone generator built with the Web Audio API
- I made an app to create personalized stories for children in 5 minutes
- Rocketship – Open-source E2E testing that's self-hostable
- We made an AI QA tester that uses VLMs to test your front-end
- OpenEvolve – open-source implementation of DeepMind's AlphaEvolve
- Markdown Ninja: open-source alternative to Substack, Mailchimp, Netlify
- TerraSTL – Open-source tool to convert map areas to STL
- I built a programming language, inspired by Golang
- Hover Effects TS – ASCII, Lego, and glitch hover effects using canvas
- Svelte Flow 1.0 is out! Rewritten for Svelte 5
- Cyberdesk, API for computer agents to control a desktop (open source)
- I Spent Years Building a FOSS Unified Zero Trust Secure Access Platform
- Centermaps – Score around 600M buildings in the whole world
- Bobber Game (Go Down to Go Up)
- Near-perfect English AI translation of a classic of Japanese literature
- Output – An AI Agent That Controls Your Computer (Mac and Windows)
- A free, privacy preserving, archive of public Discord servers
90s.dev – Game maker that runs on the web [Entertainment]
219 points, 90 comments
90s.dev is a web-based game maker inspired by the 90s era.
- Runs entirely in the browser
- Nostalgic 90s design aesthetic
- No installation required
- Enables game creation online
Discussion Link, Original Link
A Tiling Window Manager for Windows, Written in Janet [Developer Tools]
190 points, 58 comments
A keyboard-driven tiling window manager for Windows, scriptable with Janet and featuring a complete Lisp runtime.
- Keyboard-driven tiling window manager for Windows
- Scriptable with the Janet programming language
- Includes a complete Lisp runtime
- Thin wrapper library for Win32 APIs
- Inspired by StumpWM on Linux
Discussion Link, Original Link
A Simple Server to Match Long/Lat to a TimeZone [Developer Tools]
19 points, 9 comments
A simple PHP server to match latitude/longitude coordinates to a timezone.
- Uses a single-table database (MySQL-compatible)
- Lightweight and agnostic for easy integration
- Powers a companion iOS app for timezone-based features
Discussion Link, Original Link
Juvio – UV Kernel for Jupyter [Developer Tools]
91 points, 19 comments
Juvio enables inline dependency management and automatic ephemeral environment setup in Jupyter notebooks.
- Inline, PEP 723-style dependency management
- Automatic ephemeral environment setup
- Designed for Jupyter notebooks
Discussion Link, Original Link
Text to 3D simulation on a map (does history pretty well) [Research]
49 points, 42 comments
Simulate historical and real-time events on a map using text prompts, with risk analysis and multi-agent reinforcement learning for urban mobility.
- Text-to-3D simulation on a map with historical and predictive capabilities
- Risk analysis using real-time global data from social media and news
- Multi-Agent RL model for urban mobility with real census data integration
- Won AGI House World Models Hackathon
- Uses cloud and atmospheric effects libraries for enhanced visualization
Discussion Link, Original Link
Olelo Foil - NACA Airfoil Sim [Education]
28 points, 17 comments
Olelo Foil is a browser-based NACA airfoil simulator for interactive aerodynamic exploration, built with Three.js and WebGL.
- Real-time airfoil behavior visualization
- Simplified fluid models with plans for Navier-Stokes integration
- Designed for students, hobbyists, and engineers
- Part of the broader Olelo Honua STEM education platform
- Open to collaboration on physics and GPU compute improvements
Discussion Link, Original Link
Astra – a new js2exe compiler [Developer Tools]
55 points, 27 comments
Astra is a Node.js to EXE compiler focusing on CLI and server applications with strong ESM and TypeScript support.
- Uses esbuild and Node SEA for compilation
- Supports ESM and TypeScript
- Focuses on CLI and server applications (not full-stack like Electron)
- Good developer experience and CLI UX
- Currently limited to Windows and struggles with binary dependencies
Discussion Link, Original Link
Bricks – One Click Dashboards from Your Data Using AI [Business]
13 points, 10 comments
One-click AI-powered dashboard creation from uploaded data files.
- Detects data structure automatically
- Selects optimal charts and tables
- Generates plain-language insights and summaries
- Applies customizable themes
- Supports natural language prompts for adding blocks
- Exportable to PDF or shareable via live link
Discussion Link, Original Link
I made IP-to-Geo location data library for developers [Developer Tools]
5 points, 7 comments
IP-to-Geo location data library for developers.
- Super-lightweight and type-safe
- Converts any IP into geolocation data
- 100% free with unlimited uses
- Works online only
- Runs on both client and server
Discussion Link, Original Link
JavaFactory – IntelliJ plugin to generate Java code [Developer Tools]
38 points, 12 comments
An IntelliJ plugin that uses LLMs to generate repetitive Java code based on custom patterns and annotations.
- Generates Java code like implementations, tests, and fixtures
- Uses natural-language patterns and annotation-based references
- Focuses on producing code that fits project structure and passes tests
- Demo shows 400 lines of Java generated in 20 seconds with passing tests
Discussion Link, Original Link
A browser-based tone generator built with the Web Audio API [Audio]
7 points, 2 comments
A browser-based tone generator for experimenting with sound frequencies and waveforms.
- Generates tones from 20 Hz to 20,000 Hz
- Supports sine, square, triangle, and sawtooth waveforms
- Adjustable frequency, volume, and stereo pan
- Includes multi-tone, binaural beat, bass frequency, and sweep tone modes
- Useful for speaker testing, hearing tests, and sound design
Discussion Link, Original Link
I made an app to create personalized stories for children in 5 minutes [Education]
9 points, 16 comments
Create personalized children's stories in minutes with customizable characters, themes, and illustrations.
- Tailor stories with main and secondary characters
- Choose or input story themes and illustration styles
- Generate full stories with covers and illustrations
- Download as PDF instantly
- Ideal for parents or unique gifts
Discussion Link, Original Link
Rocketship – Open-source E2E testing that's self-hostable [Developer Tools]
18 points, 4 comments
Open-source, self-hostable E2E testing tool with a YAML/DSL approach for microservices and event-driven systems.
- Supports assertions beyond HTTP (e.g., file buckets, DBs, queues) via a plugin interface
- Leverages Temporal for test orchestration, scheduling, and persistence
- Designed for future AI agent integration to detect regressions
- Local version available for quick testing
Discussion Link, Original Link
We made an AI QA tester that uses VLMs to test your front-end [Developer Tools]
5 points, 0 comments
AI QA tester using VLMs to test front-end with live monitoring and bug reporting.
- Uses Vision-Language Models (VLMs) for front-end testing
- Generates bug reports and offers session replay
- Allows live test monitoring
- Free to use with login-gate for abuse prevention
Discussion Link, Original Link
OpenEvolve – open-source implementation of DeepMind's AlphaEvolve [Developer Tools]
5 points, 1 comments
OpenEvolve is an open-source implementation of DeepMind's AlphaEvolve, using LLMs to evolve and optimize entire codebases through iterative evolution.
- Open-source and configurable evolutionary coding agent
- Evolves entire codebases, not just single functions
- Uses an ensemble of LLMs with automated evaluation
- Four main components: Program Database, Prompt Sampler, LLM Ensemble, Evaluator Pool
- Supports custom problems, evaluation functions, and multiple LLM backends
- Replicated DeepMind's results (e.g., circle packing, function minimization)
- Works with OpenAI-compatible APIs and supports multi-objective optimization
- Easy setup with Python 3.9+ and simple YAML configuration
Markdown Ninja: open-source alternative to Substack, Mailchimp, Netlify [Text]
13 points, 2 comments
Markdown Ninja is an open-source, Markdown-first CMS for publishing blogs, documentation, and newsletters with a focus on simplicity and technical ease.
- Markdown-first approach for interoperability and offline work
- Unified platform for websites, newsletters, analytics, and SEO
- Fast page loading (~50ms in Europe)
- Open-source to avoid deplatforming and ensure freedom
- Simple publishing via CLI or built-in web editor
- Privacy-first analytics and no paywalls
- Supports offline workflows and git integration
Discussion Link, Original Link
TerraSTL – Open-source tool to convert map areas to STL [Design]
3 points, 0 comments
Open-source tool for converting map regions to 3D-printable STL files.
- Select any region on a map
- Export as STL file
- Ideal for terrain models and topographic visualizations
Discussion Link, Original Link
I built a programming language, inspired by Golang [Developer Tools]
6 points, 0 comments
Nature is a new programming language inspired by Golang, designed to improve upon its shortcomings while maintaining simplicity and performance.
- Improves Golang's syntax, type system, and error handling
- Features a runtime with GMP model, allocator, collector, coroutines, and channels
- Efficient compilation without relying on LLVM, enabling fast cross-compilation
- Suitable for game development, AI, IoT, CLI, and web development
- Aims to eventually replace Golang in all scenarios
- Includes a playground, documentation, and contribution guide
- Showcases projects like a packaging tool, Llama2 implementation, and Tetris
Discussion Link, Original Link
Hover Effects TS – ASCII, Lego, and glitch hover effects using canvas [Design]
6 points, 2 comments
A TypeScript utility for adding fun and experimental hover effects to images using HTML canvas.
- Applies effects like ASCII art, Lego blocks, glitch distortion, and pixelation on hover
- Lightweight and performance-friendly with GPU-accelerated canvas
- No dependencies, customizable intensity, radius, and image scope
- Includes live demo, NPM package, and GitHub repository for easy integration
- Designed for personal websites, landing pages, or error screens
Discussion Link, Original Link
Svelte Flow 1.0 is out! Rewritten for Svelte 5 [Developer Tools]
16 points, 1 comments
Svelte Flow 1.0, rewritten for Svelte 5, is now available.
- Rewritten for Svelte 5
- Version 1.0 release
Discussion Link, Original Link
Cyberdesk, API for computer agents to control a desktop (open source) [Developer Tools]
4 points, 2 comments
Cyberdesk is an open-source API for building computer agents that control virtual desktops, enabling actions like clicking, typing, and scrolling.
- Open-source infrastructure, frontend, backend, and SDKs
- Simplifies agent development by eliminating VM setup and scaling
- Supports real apps (desktop, web apps in browsers)
- Ideal for screenshot-based agents or automating computer use
- Provides demo, docs, and GitHub repository for exploration
Discussion Link, Original Link
I Spent Years Building a FOSS Unified Zero Trust Secure Access Platform [Developer Tools]
6 points, 2 comments
An open-source, self-hosted unified zero trust platform for secure access to private and public resources, serving as a modern alternative to VPNs and remote access tools.
- Open-source and self-hosted with no SaaS or paid cloud requirements
- Scalable zero trust architecture for identity-based, application-layer access
- Supports both private (WireGuard/QUIC) and public (BeyondCorp) client access
- Multi-functional: ZTNA, VPN, API gateway, AI gateway, Kubernetes ingress, and more
- Policy-as-code for context-aware access control per request
- Designed for production use with stabilized APIs and features
Discussion Link, Original Link
Centermaps – Score around 600M buildings in the whole world [Business]
3 points, 0 comments
Score around 600M buildings worldwide.
- Covers 600 million buildings globally
- Provides scoring for buildings
- Worldwide coverage
Discussion Link, Original Link
Bobber Game (Go Down to Go Up) [Entertainment]
3 points, 0 comments
A simple platformer game with a twist where you go down to go up, featuring P2P multiplayer.
- Uses
A,D, andSpacefor controls or mobile touch in portrait mode - Includes basic P2P multiplayer via PeerJS
- Built with Phaser, TypeScript, and Vite
- Designed as a learning project to avoid scope creep
Discussion Link, Original Link
Near-perfect English AI translation of a classic of Japanese literature [Text]
4 points, 0 comments
AI-powered high-quality book translation tool with near-human accuracy.
- Translates classic literature with exceptional quality
- Supports multiple languages (e.g., Japanese to English, French to English)
- Fast processing (1-2 hours per book)
- Outperforms many human translations in accuracy
- Includes public demos for verification
Discussion Link, Original Link
Output – An AI Agent That Controls Your Computer (Mac and Windows) [Productivity]
15 points, 6 comments
Output is an AI agent that controls your computer by executing tasks like filling forms, editing videos, or scheduling meetings through natural language commands.
- Works on Mac and Windows without setup or scripting
- Directly interacts with apps like Chrome, Excel, Notion, and Zoom
- Handles general-purpose tasks for various users
- Operates by clicking, typing, and navigating apps autonomously
- Early-stage product with continuous improvements
Discussion Link, Original Link
A free, privacy preserving, archive of public Discord servers [Research]
61 points, 55 comments
A free, privacy-preserving archive of public Discord servers for easy discovery and search.
- Scrapes discoverable Discord servers, focusing on informational communities like open-source projects and support groups
- Restricts searching by user ID to prevent doxing
- Simple one-click opt-out process for server owners
- Open to adding specific servers by request based on user interest