Show HN Daily Selection (2025-05-23)
- Defuddle, an HTML-to-Markdown alternative to Readability
- SQLite JavaScript - extend your database with JavaScript
- DockFlow – Switch between multiple macOS Dock layouts instantly
- Pi Co-pilot – Evaluation of AI apps made easy
- Curved Space Shader in Three.js (via 4D sphere projection)
- rtcollector - A modular, RedisTimeSeries-native observability agent
- Whenish – Plan Group Events in iMessages
- Generate huge dummy images using drag and drop
- 8-Bit Spelling Game I Built for My Daughter Using Claude AI
- send2kindle – CLI utility to send documents to your Kindle
- Infinite Hagakure
- MCP-UI – SDK that embeds interactive UI snippets via MCP
- I built an interactive website to practice English at your own pace
- FlightsRefund – AI to automate flight refund claims
- MMDL – A front end for CalDAV tasks and events
- I created an tool that creates interactive product demos in 2 minutes
- Nostria – A peer-to-peer social protocol that avoids centralized relays
- Built our open source dev tool in 6 hours using tool to build itself
- Find prompts that jailbreak your agent (open source)
- I built a SaaS that lets you create digital manuals with drag and drop
- I made a 1 minute portfolio website builder for designers and devs
Defuddle, an HTML-to-Markdown alternative to Readability [Developer Tools]
75 points, 13 comments
Defuddle is an open-source JavaScript library that parses web pages to extract main content and metadata, converting it to Markdown.
- Extracts main content and metadata from web pages
- Converts HTML content to Markdown format
- Available as both a JS library and CLI tool
- MIT-licensed, open-source project
- Designed as an alternative to Mozilla's abandoned Readability
- Useful for building read-it-later apps
Discussion Link, Original Link
SQLite JavaScript - extend your database with JavaScript [Developer Tools]
135 points, 41 comments
SQLite JavaScript allows extending SQLite databases with JavaScript functionality.
- Enables JavaScript integration within SQLite databases
- Extends database capabilities with custom JavaScript functions
Discussion Link, Original Link
DockFlow – Switch between multiple macOS Dock layouts instantly [Productivity]
51 points, 35 comments
DockFlow allows macOS users to instantly switch between multiple Dock layouts for different tasks.
- Save and switch between multiple Dock configurations
- Assign custom hotkeys to change layouts instantly
- Add apps, folders, files, or links to your Dock
- Insert visual spacers to group items
- Lightweight and macOS-native (no permissions or custom dock)
- Supports macOS 13.5 and above
- Includes CLI tools and Shortcuts integration
- One-time payment (€4.99 launch price, increasing to €9.99 on June 1)
Discussion Link, Original Link
Pi Co-pilot – Evaluation of AI apps made easy [Developer Tools]
21 points, 5 comments
Pi Co-pilot helps developers define and apply nuanced evaluations to LLM outputs for quality assessment.
- Converts examples, prompts, or old evals into a scoring spec with 10-20 concrete questions
- Uses fast encoder-based models or Python functions for scoring
- Integrates with Python, TypeScript, Promptfoo, Langfuse, and spreadsheets
- Offers a conversational interface to refine evaluations iteratively
- Provides $10 free credits (25M input tokens) for testing without sign-in
Discussion Link, Original Link
Curved Space Shader in Three.js (via 4D sphere projection) [Developer Tools]
56 points, 19 comments
A GLSL shader that bends 3D space using a 4D hypersphere projection.
- Projects 3D models onto a 4D sphere
- Rotates the sphere in 4D space
- Projects back to 3D for curved space effects
Discussion Link, Original Link
rtcollector - A modular, RedisTimeSeries-native observability agent [Developer Tools]
5 points, 0 comments
A modular, RedisTimeSeries-native observability agent designed as a lightweight alternative to Telegraf for collecting and pushing metrics to Redis.
- Written in Python and configured with YAML
- Supports Linux, macOS, Docker, Redis, MySQL, and PostgreSQL metrics
- Designed for simplicity, extensibility, and Redis-first integration
- Future plans include logs via RedisJSON, traces via Redis Streams, and Grafana dashboards
- Ideal for homelabs, edge deployments, and minimal-metric setups
Discussion Link, Original Link
Whenish – Plan Group Events in iMessages [Productivity]
31 points, 43 comments
Whenish is an iMessage app for planning group events by selecting multiple available dates directly in chats.
- Simplifies scheduling by allowing users to pick dates in iMessage
- Designed for group chats to coordinate event timing
- Initial positive feedback from early users
- First public release with plans for future features
Discussion Link, Original Link
Generate huge dummy images using drag and drop [Image]
3 points, 0 comments
Quickly generate dummy images of various dimensions for testing via drag and drop.
- Supports unusual dimensions (e.g., 1x1 px, 2x20,000 px)
- Simple drag-and-drop interface
- Open-source project
- Limited by browser constraints for extremely large dimensions
Discussion Link, Original Link
8-Bit Spelling Game I Built for My Daughter Using Claude AI [Education]
7 points, 4 comments
A retro-style spelling game created for a child using Claude AI to provide immediate feedback and encourage learning.
- Designed with an 8-bit aesthetic for a fun, nostalgic feel
- Uses Claude AI to offer real-time feedback on spelling
- Helps children study and improve spelling skills
- Continuously refined based on user experience observations
- Created as a supportive tool for an upcoming spelling test
Discussion Link, Original Link
send2kindle – CLI utility to send documents to your Kindle [Productivity]
4 points, 0 comments
Send documents to your Kindle via CLI.
- Command-line utility
- Supports sending documents directly to Kindle
- Simple and efficient workflow
Discussion Link, Original Link
Infinite Hagakure [Text]
26 points, 11 comments
Infinite-scrolling digital version of Hagakure: The Book of the Samurai, inspired by Ghost Dog and Yukio Mishima.
- Inspired by the aesthetic and philosophy of Hagakure
- Infinite-scrolling format for continuous reading
- Shared reading experience, starting at the same point for all users
- Simple execution of a personal passion project
Discussion Link, Original Link
MCP-UI – SDK that embeds interactive UI snippets via MCP [Developer Tools]
5 points, 0 comments
MCP-UI is an open-source SDK that enables embedding interactive UI components via the Model Context Protocol (MCP) for enhanced AI interactions.
- Provides lean client and server SDKs for passing rich UI components over MCP
- Supports rendering UI snippets via raw HTML or external apps
- Handles follow-up interactions through events (e.g., tool calls)
- Includes demo projects like a UI-enabled chat client and local development inspector
- Aims to improve delivery methods (e.g., React Server Components, Remote-DOM) and protocol negotiation
Discussion Link, Original Link
I built an interactive website to practice English at your own pace [Education]
3 points, 0 comments
Interactive website for self-paced English practice.
- Self-paced learning
- Interactive exercises
- No text provided for additional details
Discussion Link, Original Link
FlightsRefund – AI to automate flight refund claims [Travel]
5 points, 2 comments
AI-powered tool to automate flight refund claims.
- Automates the process of claiming flight refunds
- Uses AI to handle claims efficiently
- Simplifies the refund process for users
Discussion Link, Original Link
MMDL – A front end for CalDAV tasks and events [Productivity]
3 points, 0 comments
A front-end interface for managing CalDAV tasks and events.
- Simplifies interaction with CalDAV servers
- Supports task and event management
- Designed for ease of use
Discussion Link, Original Link
I created an tool that creates interactive product demos in 2 minutes [Business]
53 points, 8 comments
Interactive product demo creation tool that works in just 2 minutes.
- Quick setup (2 minutes)
- Interactive demos
- No text input required
Discussion Link, Original Link
Nostria – A peer-to-peer social protocol that avoids centralized relays [Consumer Tech]
5 points, 2 comments
Nostria is a fully peer-to-peer social protocol designed to eliminate reliance on centralized relays in the Nostr ecosystem.
- Peer-to-peer architecture avoids centralized message relays
- Led by open-source contributor Sondre Bjellås
- Currently raising pre-seed funding for MVP development
- Seeks community feedback on approach and technical issues
Discussion Link, Original Link
Built our open source dev tool in 6 hours using tool to build itself [Developer Tools]
5 points, 0 comments
Open-source dev tool built in 6 hours using itself.
- Self-building tool
- Open-source
- Rapid development (6 hours)
Discussion Link, Original Link
Find prompts that jailbreak your agent (open source) [Developer Tools]
8 points, 0 comments
An open-source tool for stress-testing AI agents by simulating prompt injection attacks to identify vulnerabilities.
- Implements attack strategies based on the AdvPrefix paper for nuanced LLM jailbreaks
- Generates adversarial prefixes likely to bypass agent safeguards
- Outputs a list of high-risk prompts for security testing
- Aims to be the go-to toolkit for AI agent security testing
- Open-source with ongoing development for more attack strategies
Discussion Link, Original Link
I built a SaaS that lets you create digital manuals with drag and drop [Productivity]
6 points, 4 comments
A drag-and-drop SaaS tool for creating structured digital manuals without design or coding skills.
- No design or coding expertise required
- Drag-and-drop editor for easy document creation
- Automatically handles formatting without AI
- Used for onboarding and process documentation
- Seeking feedback on positioning and use cases
Discussion Link, Original Link
I made a 1 minute portfolio website builder for designers and devs [Design]
4 points, 0 comments
A free 1-minute portfolio website builder for designers and developers.
- Quick setup in just 1 minute
- Free to use
- Designed for designers and developers