Show HN Daily Selection (2025-06-06)

• Claude Composer
• Ask-human-mcp – zero-config human-in-loop hatch to stop hallucinations
• ClickStack – Open-source Datadog alternative by ClickHouse and HyperDX
• String Flux – Simplify everyday string transformations for developers
• Container Use for Agents
• iOS Screen Time from a REST API
• I made a 3D SVG Renderer that projects textures without rasterization
• Grab a Random ArXiv Paper
• MCP-Cloud – One-click hosting for MCP servers (50 templates)
• Create LLM graders and run evals in JavaScript with one file
• JSON_fast – 35% faster JSON parsing than serde_JSON
• patdb: a snappy + easy + pretty TUI debugger for Python
• This database never puts you on hold
• Run 30B model in 4GB Active Memory
• Open a browser by clapping twice (inspired by Iron Man)
• Create tailored resumes based on job descriptions
• I built Claude code but for image generation
• The first portable, customisable General AI Agent – available for free
• I built an old photo restoration tool using the Flux Kontext
• Clarity – A Dashboard for Scrum Teams (Early Access)
• Uzbekistan advanced to the World Championship after 34 years
• MailShrimp – validate email lists with risk level and confidence score
• Heynds – Write Faster – AI Voice and Writing Assistant (Mac/Windows)

Claude Composer [ChatBots]

19 points, 8 comments

A customizable "yolo mode" for Claude with fine-grained controls and preset tool permissions.

• Adjustable "yolo" intensity levels
• Preset configurations for tools and permissions
• Easy-to-use interface for customization

Discussion Link, Original Link

Ask-human-mcp – zero-config human-in-loop hatch to stop hallucinations [Developer Tools]

4 points, 2 comments

A zero-config tool to pause AI agents and prompt human input when they encounter uncertainty or hallucinations.

• Zero setup: Install via pip and add one line to config
• Cross-platform: Works on macOS, Linux, and Windows
• Markdown-based Q&A: Logs questions in ask_human.md for manual answers
• File management: Prevents corruption, limits pending questions, and auto-rotates logs
• Seamless integration: Resumes agent execution once answers are provided

Discussion Link, Original Link

ClickStack – Open-source Datadog alternative by ClickHouse and HyperDX [Developer Tools]

153 points, 33 comments

ClickStack is an open-source observability stack powered by ClickHouse and HyperDX for collecting, visualizing, and alerting on telemetry data.

• Combines logs, metrics, and traces in a single view for comprehensive debugging
• Uses ClickHouse for high-performance, cost-effective storage
• Supports OpenTelemetry for easy data ingestion
• Offers a user-friendly UI with lucene-like search and SQL mode for complex queries
• Includes high-cardinality outlier analysis for anomaly detection
• Simple deployment via Docker and a browser-based live demo
• Open-source (Apache2/MIT licenses) with no restrictive retention limits

Discussion Link, Original Link

String Flux – Simplify everyday string transformations for developers [Developer Tools]

6 points, 2 comments

String Flux simplifies string transformations for developers with a clean UI and smart suggestions.

• Supports multiple string operations like decoding, formatting, etc.
• Allows chaining transformations in a single flow for complex tasks.
• Cleaner, more focused UI compared to similar tools like CyberChef.
• Smart suggestions based on input to streamline workflows.
• Useful for handling encoded API responses or nested log data.

Discussion Link, Original Link

Container Use for Agents [Developer Tools]

26 points, 5 comments

Container Use for Agents

• Enables containerization for agent-based applications
• Simplifies deployment and management of agent systems

Discussion Link, Original Link

iOS Screen Time from a REST API [Productivity]

75 points, 41 comments

Clearspace provides a REST API to access iOS Screen Time data, enabling developers to build custom solutions for screen time management.

• First web-accessible API for iOS Screen Time data
• Enables custom integrations like charity donations, group tracking, and therapist reporting
• Aims to address misalignment between human attention and digital intentions
• Demo available for setup and usage

Discussion Link, Original Link

I made a 3D SVG Renderer that projects textures without rasterization [Design]

195 points, 69 comments

3D SVG Renderer that projects textures without rasterization.

• Renders 3D graphics in SVG format
• Projects textures without rasterization
• Preserves vector quality for scalability

Discussion Link, Original Link

Grab a Random ArXiv Paper [Research]

8 points, 1 comments

Random arXiv paper fetcher with topic-weighted selection.

• Selects a random topic from arXiv categories (CS, Econ, Math, etc.)
• Queries a random paper within the chosen topic
• Favors less common topics in distribution
• Open to feedback and improvements

Discussion Link, Original Link

MCP-Cloud – One-click hosting for MCP servers (50 templates) [Developer Tools]

7 points, 1 comments

One-click hosting for MCP servers with 50 templates.

• One-click hosting
• Supports MCP servers
• Offers 50 templates

Discussion Link, Original Link

Create LLM graders and run evals in JavaScript with one file [Developer Tools]

26 points, 2 comments

A JavaScript tool for creating LLM graders and running evaluations with minimal setup.

• Easily grade and evaluate LLM outputs using a simple JSONL file format
• Supports multiple models via OpenRouter integration
• Uses LLM-as-grader approach to measure output quality against queries
• Encourages TDD-style prompt refinement with synthetic data generation
• Designed for reliability and structured debugging in LLM apps

Discussion Link, Original Link

JSON_fast – 35% faster JSON parsing than serde_JSON [Developer Tools]

3 points, 0 comments

JSON_fast is a Rust library offering faster JSON parsing than serde_json through zero-copy techniques and smart caching.

• 35% faster JSON parsing than serde_json
• Uses zero-copy techniques for efficiency
• Implements smart caching to optimize performance
• Developed as the author's first Rust project

Discussion Link, Original Link

patdb: a snappy + easy + pretty TUI debugger for Python [Developer Tools]

3 points, 0 comments

A snappy, easy-to-use, and visually appealing TUI debugger for Python.

• Fast performance
• Simple and intuitive interface
• Pretty text-based UI
• Designed for Python debugging

Discussion Link, Original Link

This database never puts you on hold [Developer Tools]

6 points, 2 comments

Wildcat is an experimental open-source embedded persistent storage engine using an LSM tree design to address multi-writer bottlenecks.

• Implements LSM tree similar to RocksDB and LevelDB
• Focuses on solving multi-writer bottlenecks in embedded systems
• Includes optimizations for write and read paths
• Open-source and experimental project

Discussion Link, Original Link

Run 30B model in 4GB Active Memory [Developer Tools]

4 points, 1 comments

Optimized sparse transformer kernels enable running a 30B model in just 4GB active memory with significant performance improvements.

• 5X faster MLP layer performance in transformers
• 50% lower memory consumption by avoiding inactive nodes
• 1.6-1.8x throughput increase for Llama 3.2
• 26.4% memory reduction (6.125GB → 4.15GB)
• Open-sourced on GitHub (NimbleEdge/sparse_transformers)

Discussion Link, Original Link

Open a browser by clapping twice (inspired by Iron Man) [Consumer Tech]

8 points, 2 comments

A Python script that opens Google Chrome or a local file when detecting two claps, inspired by Iron Man.

• Uses MATLAB for frequency analysis (1.4–1.8kHz range) of clap sounds
• Real-time detection in Python with a bandpass filter and peak detection
• Fun and novel way to trigger actions like opening Netflix or presentations
• GitHub repository available for customization and experimentation

Discussion Link, Original Link

Create tailored resumes based on job descriptions [Productivity]

3 points, 0 comments

Create tailored resumes based on job descriptions in seconds.

• Generates customized resumes from job descriptions
• Outputs resumes in PDF format
• Quick and easy process with copy-paste functionality

Discussion Link, Original Link

I built Claude code but for image generation [Image]

5 points, 2 comments

AI-powered image generation with iterative refinement through agentic evaluation.

• Extends Claude Code's agentic capabilities to image generation
• Generates images and iteratively improves them via evaluation loops
• Identifies and fixes flaws in generated images automatically

Discussion Link, Original Link

The first portable, customisable General AI Agent – available for free [Life Assistant]

5 points, 1 comments

A portable, customizable General AI Agent that works across multiple platforms with no coding required.

• Works seamlessly with ChatGPT, Claude, Cursor, and other AI platforms
• Free to use with no API credits needed
• Platform-agnostic technology leverages each LLM's strengths
• Customizable via natural language instructions (no coding)
• Upcoming Flow visual designer for easy agent creation
• Democratizes access to AI agents for non-technical users

Discussion Link, Original Link

I built an old photo restoration tool using the Flux Kontext [Image]

15 points, 8 comments

AI-powered old photo restoration tool using Flux Kontext for quick and high-quality enhancements.

• Restores old photos and fixes damage
• Colorizes black-and-white images
• Processes images in seconds
• Free to use

Discussion Link, Original Link

Clarity – A Dashboard for Scrum Teams (Early Access) [Productivity]

4 points, 0 comments

A lightweight dashboard for Scrum teams providing instant insights into team health, ticket quality, and velocity.

• No setup or integrations required to start
• Optional Jira integration
• AI-powered insights
• Designed for Scrum Masters and Product Owners
• Early access version seeking feedback

Discussion Link, Original Link

Uzbekistan advanced to the World Championship after 34 years [Entertainment]

3 points, 0 comments

Uzbekistan's national team qualifies for the World Championship after 34 years.

• Historic qualification after 34 years
• National team achievement
• Significant milestone for Uzbekistan football

Discussion Link

MailShrimp – validate email lists with risk level and confidence score [Business]

3 points, 5 comments

MailShrimp is an email validation tool that categorizes email addresses by risk level and provides a confidence score.

• Validates email syntax, format, DNS/MX records, and SMTP
• Detects disposable and catch-all email addresses
• Provides risk categories (valid, risky, invalid) and confidence scores
• Fast processing with human-readable results and exportable data
• Supports CSV uploads and will offer an API soon

Discussion Link, Original Link

Heynds – Write Faster – AI Voice and Writing Assistant (Mac/Windows) [Productivity]

4 points, 0 comments

Heynds is a desktop app for macOS and Windows (Linux coming soon) that combines voice dictation with an AI writing assistant to boost productivity.

• Real-time voice-to-text transcription for faster content creation
• AI-powered writing assistant for reformatting, polishing, and generating text
• Works across any desktop application (Slack, Notion, Gmail, etc.)
• Uses Gemini Flash for AI and Groq Whisper Large V3 Turbo for speech-to-text
• Supports custom API keys for lifetime plan users

Discussion Link, Original Link