AI and engineering tools - simonwillison.net

The tools on tools.simonwillison.net were mostly built using AI-assisted programming. This page lists 106 tools and their development history.

Serving 200 million requests per day with a cgi-bin

Jake Gold tests how well 90s-era CGI works today, using a Go + SQLite CGI program running on a 16-thread AMD 3700X. Using CGI on modest hardware, it’s...

Announcing Toad—a universal UI for agentic coding in the terminal

Will McGugan is building his own take on a terminal coding assistant, in the style of Claude Code and Gemini CLI, using his Textual Python library as ...

System Card: Claude Opus 4 & Claude Sonnet 4

Direct link to a PDF on Anthropic’s CDN because they don’t appear to have a landing page anywhere for this document. Anthropic’s system cards are alwa...

WeLoveNoCode

Platform connecting businesses with no-code developers and tools.

Rownd

Customer identity and data privacy platform for businesses.

User Interviews

Platform connecting companies with participants for user research and customer feedback studies.

Canua

Financial data analytics platform for consumers and investment professionals.

AI Company Research Tool

Web app for AI-driven company research

aVenture.vc

Data-driven research platform for the VC ecosystem

SearchAI

AI-powered web search with a contextual chat assistant

repo-tokens-calculator

CLI token counter (Python + tiktoken + uv) with pretty summary