Show HN Daily Selection (2025-09-05)
- I built FlipCards – a flashcard app with variations to improve learning
- A Map of All YC Companies (5,300 Startups by Batch and Location)
- Shimmy – 5MB privacy-first, local alternative to Ollama (680MB)
- Provable Safety for AI Agents
- Prototyper – AI design platform with its own compiler and runtime
- SHAde – A tool that turns Git Commit Hashes into deterministic Art
- Built a civic issue certificate app in 1 hour (200k views)
- Vapor – A notepad that fades away as you type
I built FlipCards – a flashcard app with variations to improve learning [Education]
36 points, 23 comments
A flashcard app that enhances learning through multiple variations of each card and spaced repetition.
- Supports creating cards for various subjects like math, languages, and coding
- Uses multiple variations per card to deepen understanding
- Randomly selects variations to prevent rote memorization
- Implements SM2 spaced repetition for long-term retention
- Offers free tier with limited features and paid plans for unlimited use
Discussion Link, Original Link
A Map of All YC Companies (5,300 Startups by Batch and Location) [Business]
63 points, 40 comments
A map displaying 5,300 Y Combinator startups organized by batch and location.
- Visualizes YC companies geographically
- Filters by batch
- Includes 5,300 startups
- Interactive map interface
Discussion Link, Original Link
Shimmy – 5MB privacy-first, local alternative to Ollama (680MB) [Developer Tools]
4 points, 6 comments
Shimmy is a lightweight, privacy-first local alternative to Ollama with a significantly smaller footprint.
- Only 5MB in size (compared to Ollama's 680MB)
- Privacy-focused design
- Runs locally for enhanced security
Discussion Link, Original Link
Provable Safety for AI Agents [Developer Tools]
3 points, 1 comments
Provable Safety for AI Agents
- Ensures AI agents operate within predefined safety parameters
- Uses formal verification methods to guarantee compliance
- Aims to prevent unintended or harmful behaviors in AI systems
Discussion Link, Original Link
Prototyper – AI design platform with its own compiler and runtime [Design]
8 points, 4 comments
Prototyper is an AI-driven design platform featuring a custom compiler and runtime for enhanced LLM-generated design control.
- Custom compiler and runtime without third-party dependencies
- Instant feedback with no compile/refresh delays
- Deterministic design controls integrated with LLM-generated code
- Tight coupling of inference and live code execution
- Free trial available for early users
Discussion Link, Original Link
SHAde – A tool that turns Git Commit Hashes into deterministic Art [Design]
3 points, 0 comments
A command-line tool that converts Git commit hashes into deterministic geometric art using pseudorandom patterns and perceptually uniform color palettes.
- Generates unique visual fingerprints from Git commit SHA-256 hashes
- Uses pseudorandom number generation for geometric patterns (bars, spirals)
- Produces visually coherent colors via CIELAB/LCH color spaces
- Outputs SVG, PNG, or HTML galleries of commit history
- Supports animations showing transitions between commits
- Stateless and deterministic—same hash always yields the same image
- Open-source Python implementation
Discussion Link, Original Link
Built a civic issue certificate app in 1 hour (200k views) [Productivity]
4 points, 0 comments
One-sentence civic issue certificate app built in an hour that went viral with 200k+ views.
- Created in response to a Twitter request
- Gained 200k+ views in 2 days
- Incorporated live user feedback
- Added analytics and disclaimers
- Open-sourced the project
Discussion Link, Original Link
Vapor – A notepad that fades away as you type [Text]
5 points, 4 comments
A minimalist notepad that encourages stream-of-consciousness writing by fading text as you type.
- Text disappears after typing, preventing edits or backtracking
- No formatting, selection, or editing features
- Supports saving content as a .txt file
- Designed to promote forward-thinking writing without self-editing