Show HN Daily Selection (2025-07-30)
- I built an AI that turns any book into a text adventure game
- A GitHub Action that quizzes you on a pull request
- Monchromate – Smart greyscale browser extension
- Terminal-Bench-RL: Training Long-Horizon Terminal Agents with RL
- BreathylBox – A lockbox that only opens when you're sober
- Xorq – open compute catalog for AI
- ELF Injector
- TanStack DB – Reactive DB with Differential Dataflow for TanStack Query
- Maia Chess – Human-like chess AI for playing, learning, and more
- Wush-Action – SSH into GitHub Actions over WireGuard
- Gogg – A GOG game downloader written in Go
- I waste my time extracting stuff every week from the Internet
- YouTubeTldw: ad‑free, login‑free YouTube summaries in a flash
- PolyglotGPT – Conversational AI for Learning 40 Languages
- Suggest – Ultra-low-friction feedback for your website
- Walk-through of rocket landing optimization paper [pdf]
- Same prompt tested across Replit, Bolt, v0, Lovable and Raq.com
- Agentic Coding Tools – Directory for AI agents and vibe coders
- API Radar – Real-time GitHub scanner for exposed API keys
- Draw A Fish and watch it swim with the others
- Fix Your Damn Posture!
- 4KFilmDb – A tool to track and analyze 4K movies (HDR, Dolby Atmos)
I built an AI that turns any book into a text adventure game [Entertainment]
179 points, 74 comments
AI-powered web app that converts books into interactive text adventure games with customizable genres.
- Transforms any book into a playable text adventure
- Allows user choices to shape the story
- Supports genre remixing (e.g., Dune as noir detective)
- Currently in development, open to feedback
Discussion Link, Original Link
A GitHub Action that quizzes you on a pull request [Developer Tools]
58 points, 22 comments
AI-powered GitHub Action that quizzes developers on pull requests before merging.
- Generates quizzes from PRs using AI to ensure code understanding
- Configurable options like LLM model, max attempts, and minimum diff size
- Runs locally with ngrok for temporary quiz URLs, keeping code private
- Supports reasoning models for better question quality (though more expensive)
- Only sends code to model provider (OpenAI) for processing
Discussion Link, Original Link
Monchromate – Smart greyscale browser extension [Consumer Tech]
28 points, 3 comments
A browser extension that converts web pages to greyscale with customizable features.
- Converts web pages to greyscale
- Supports site exclusion to avoid greyscale on work sites
- Includes scheduler and intensity control
- Compatible with Chrome, Firefox, and other browsers
- Open-source with positive user feedback
Discussion Link, Original Link
Terminal-Bench-RL: Training Long-Horizon Terminal Agents with RL [Developer Tools]
102 points, 9 comments
A reinforcement learning framework for training long-horizon terminal/coding agents, scalable from 2x A100s to 32x H100s.
- Uses a Claude Code-inspired agent with system messages and tools
- Features Docker-isolated GRPO training with per-rollout containers
- Includes a multi-agent synthetic data pipeline for generating and validating training data
- Implements a hybrid reward signal combining unit test verifiers and an LLM judge
- Achieved 13.75% on Terminal-Bench with an untrained Qwen3-32B agent
- Supports simple config presets for multiple hardware setups
- Open-sourced with agent, data, and code available on GitHub
Discussion Link, Original Link
BreathylBox – A lockbox that only opens when you're sober [Health]
3 points, 0 comments
A lockbox that only opens when the user passes a breathalyzer test and enters a passcode, aimed at preventing access to items like car keys or firearms while intoxicated.
- Requires breathalyzer test and passcode authentication to unlock
- Targets multiple use cases (car keys, gun safety, tech reduction)
- Currently validating demand before manufacturing
- Seeks feedback on legal, hardware, and prioritization concerns
Discussion Link, Original Link
Xorq – open compute catalog for AI [Developer Tools]
34 points, 8 comments
Xorq is an open-source compute catalog designed to standardize and simplify AI compute transformations, features, models, and pipelines across engines.
- Built on Arrow Flight for high-speed data transport and Ibis for cross-engine expression trees
- Offers pandas-style declarative transformations with multi-engine execution (e.g., DuckDB, Snowflake)
- Provides portable UDFs as Flight endpoints and serveable transforms
- Includes built-in caching, lineage tracking, and diff-able YAML artifacts for CI/CD
- Supports feature stores, semantic layers, and ML integration with Python simplicity and SQL-scale performance
- Open-source with a CLI tool and UI console for visualization and troubleshooting
Discussion Link, Original Link
ELF Injector [Developer Tools]
33 points, 10 comments
ELF Injector enables injecting relocatable code chunks into ELF executables to run before the original entry point.
- Allows injecting arbitrary-sized code chunks
- Runs injected code before the original entry point
- Includes sample chunks and a step-by-step tutorial
- Written in C and assembly
- Currently supports 32-bit ARM, easily portable to other architectures
Discussion Link, Original Link
TanStack DB – Reactive DB with Differential Dataflow for TanStack Query [Developer Tools]
4 points, 0 comments
TanStack DB is a reactive client database for TanStack Query that enables sub-millisecond updates with differential dataflow and real-time synchronization.
- Uses Differential Dataflow for efficient incremental recomputation
- Supports live queries, optimistic updates, and streaming joins
- Works with REST, GraphQL, WebSockets, and sync engines like ElectricSQL or Firebase
- Enables real-time updates without manual bookkeeping
- Integrates seamlessly with TanStack Query for incremental adoption
Discussion Link, Original Link
Maia Chess – Human-like chess AI for playing, learning, and more [Education]
7 points, 1 comments
Maia Chess is a human-like chess AI platform for playing, learning, and analyzing games, now in open beta.
- Play against Maia-2, a human-like chess engine tailored to your skill level
- Analyze games with both Maia’s human-based predictions and Stockfish evaluations
- Solve Maia-powered tactics puzzles with unique insights
- Practice openings with instant, personalized feedback
- Play Hand & Brain, a team variant where you collaborate with Maia
- Test your skills in Bot-or-not, a chess Turing Test challenge
- Compete on leaderboards across different modes
- Backed by research from the University of Toronto, with multiple published papers
Discussion Link, Original Link
Wush-Action – SSH into GitHub Actions over WireGuard [Developer Tools]
7 points, 0 comments
SSH into GitHub Actions over WireGuard.
- Secure remote access to GitHub Actions via SSH
- Uses WireGuard for encrypted tunneling
- Simplifies debugging and troubleshooting workflows
Discussion Link, Original Link
Gogg – A GOG game downloader written in Go [Entertainment]
3 points, 0 comments
A cross-platform open-source tool in Go for downloading and backing up GOG.com game libraries.
- Scriptable CLI and easy-to-use GUI
- Multi-threaded and resumable downloads
- Filters for platform, language, DLCs, etc.
- File verification with hashes and total size calculation
I waste my time extracting stuff every week from the Internet [Productivity]
3 points, 0 comments
A personal curation tool for filtering and selecting relevant content from 150 news feeds using LLMs and manual swiping.
- Uses 150 curated news feeds, including Hacker News
- Pre-filters content with lightweight LLMs to exclude unwanted topics
- Manual selection via a Tinder-like swiping interface
- Focuses on open-source software, human-written inspiring text, and avoids commercial content
- Processes ~2500 items weekly, requiring significant time investment
- Seeks ways to optimize without fully automating human curation
Discussion Link, Original Link
YouTubeTldw: ad‑free, login‑free YouTube summaries in a flash [Video]
5 points, 2 comments
An open-source website that provides quick, ad-free, and login-free summaries of YouTube videos using the tldw Python library.
- Uses the tldw Python library for fast video summarization
- No ads or login required
- Completely free to use
- Open-source with code available on GitHub
Discussion Link, Original Link
PolyglotGPT – Conversational AI for Learning 40 Languages [Education]
3 points, 0 comments
AI-powered language learning assistant for practicing and improving fluency in 40 languages.
- Supports conversational practice in native or target language
- Corrects mistakes and answers grammar/vocabulary questions
- Includes translation and romanization features
- Explains highlighted words/phrases in AI responses
Discussion Link, Original Link
Suggest – Ultra-low-friction feedback for your website [Business]
4 points, 2 comments
Ultra-low-friction feedback widget that captures user rageclicks and pairs feedback with session replays for context.
- Triggers when users rageclick, capturing real-time frustration points
- Saves full session replays with feedback for easy issue reproduction
- Takes just 4 seconds to leave feedback, minimizing disruption
- Works alongside existing tools without requiring replacements
- Used for both external user feedback and internal team bug reporting
Discussion Link, Original Link
Walk-through of rocket landing optimization paper [pdf] [Education]
4 points, 1 comments
Expanded walk-through of a rocket landing trajectory optimization paper with code implementation.
- Detailed explanation of complex rocket landing trajectory concepts
- Includes source code for practical implementation
- Designed to make the topic more approachable for others
- Open to feedback for continuous improvement
Discussion Link, Original Link
Same prompt tested across Replit, Bolt, v0, Lovable and Raq.com [Developer Tools]
6 points, 0 comments
Raq.com is a platform that uses Claude Code to build functional internal tools directly in the browser, outperforming other AI coding tools in real-world API integration tests.
- Uses Claude Code for self-correcting, working solutions from a single prompt
- Provisions isolated Docker environments for each company (dev and prod)
- Persistent terminal in dev environment for uninterrupted sessions
- Includes CLAUDE.md with best practices for Laravel + Filament stack
- Self-Correction Loop allows Claude to test and debug its own work
- One-click deployment from dev to prod with rsync, migrations, and cache clearing
Discussion Link, Original Link
Agentic Coding Tools – Directory for AI agents and vibe coders [Developer Tools]
4 points, 2 comments
A directory of AI-powered coding tools for autonomous app building, CLI agents, and multi-agent development platforms.
- Features tools that plan, scaffold, and write code with minimal input
- Filterable by autonomy level, LLMs used, pricing, and open-source status
- Compact UI with mobile support, dark mode, and no signups
- Includes both polished and experimental tools
- Requests feedback on missing tools, organization, and additional info
Discussion Link, Original Link
API Radar – Real-time GitHub scanner for exposed API keys [Developer Tools]
3 points, 1 comments
Real-time GitHub scanner for detecting and redacting exposed API keys in public commits.
- Scans public GitHub commits in real time for leaked API keys
- Uses pattern matching and validation heuristics for detection
- Partially redacts keys but allows copying for verified leaks
- Features leaderboards for leaky repositories and exposed providers
- Built with Node.js, MongoDB, Redis, and Next.js
- Designed to promote developer security awareness
- Supports OpenAI, Google Gemini, Anthropic Claude, and more
Discussion Link, Original Link
Draw A Fish and watch it swim with the others [Entertainment]
4 points, 4 comments
Draw a fish and watch it swim with others in a shared interactive environment.
- Interactive drawing tool for creating fish
- Shared virtual space where drawn fish swim together
- Real-time visualization of user-created fish interacting
Discussion Link, Original Link
Fix Your Damn Posture! [Health]
4 points, 0 comments
Turn your AirPods into a real-time posture coach.
- Uses AirPods for posture monitoring
- Provides real-time feedback
- Helps improve posture habits
Discussion Link, Original Link
4KFilmDb – A tool to track and analyze 4K movies (HDR, Dolby Atmos) [Entertainment]
3 points, 0 comments
4KFilmDb is an independent database for tracking and comparing 4K movie streaming quality across platforms like Netflix and Disney+.
- Tracks HDR, bitrates, and Dolby Atmos audio
- Includes smart filters and presets for easy discovery
- Identifies fake HDR titles with poor quality grades
- Currently in beta, accepting feedback