RegExr is an online tool to learn, build, & test Regular Expressions (RegEx / RegExp).
regex101: build, test, and debug regex
Regular expression tester with syntax highlighting, explanation, cheat sheet for PHP/PCRE, Python, GO, JavaScript, Java, C#/.NET, Rust.
Fast regex search: indexing text for agent tools · Cursor
How we're building indexes for regular expression search so agents can find text in large monorepos without the 15-second ripgrep waits.
brevity1swos/rgx
regex101 for the terminal — real-time matching, 3 engines, capture groups, replace mode, syntax highlighting, plain-English explanations, undo/redo, mouse support. Written in Rust.
A DEVELOPER PROVED THE REGEX YOU'VE WRITTEN A THOUSAND TIMES IS SECRETLY A COMPILER AND THAT ALMOST NO ONE WHO USES THEM HAS ANY IDEA WHAT ACTUALLY RUNS 36 minutes from Paul Wankadia, the engineer behind a regex engine that compiles your pattern straight down to raw machine code https://t.co/pMhg9AxYbJ
A DEVELOPER PROVED THE REGEX YOU'VE WRITTEN A THOUSAND TIMES IS SECRETLY A COMPILER AND THAT ALMOST NO ONE WHO USES THEM HAS ANY IDEA WHAT ACTUALLY RUNS36 minutes from Paul Wankadia, the engineer behind a regex engine that compiles your pattern straight down to raw machine code… https://t.co/XgyFxNmImW pic.twitter.com/pMhg9AxYbJ— slash1s (@slash1sol) June 5, 2026
le0pard/re2js
RE2JS is the JavaScript port of RE2, a regular expression engine that provides linear time matching
Markdown Guide
A free and open-source reference guide that explains how to use Markdown.
Automator User Guide for Mac
Learn how to use Automator on your Mac to automate much of what you do on your computer.
Semble: Fast and Accurate Code Search for Agents
Fast and Accurate Code Search for Agents. Uses ~98% fewer tokens than grep+read
Compiling Match Statements to Bytecode
Full pipeline deep dive for purple garden: AST, BB SSA IR, Bytecode, Optimisations
bradleyjkemp/grpc-tools
A suite of gRPC debugging tools. Like Fiddler/Charles but for gRPC.
Building an Open-Source Alternative to Cursor with Code Context - Milvus Blog
Code Context—an open-source, MCP-compatible plugin that brings powerful semantic code search to any AI coding agent, Claude Code and Gemini CLI, IDEs like VSCode, and even environments like Chrome.
OG Check - Free Open Graph Meta Tags Checker & Validator Tool
Free online Open Graph checker and validator. Analyze, preview and optimize your website's meta tags for better social media sharing on Facebook, Twitter, LinkedIn. Generate OG code instantly.
Vim anti-patterns | Arabesque
The benefits of getting to grips with Vim are immense in terms of editing speed and maintaining your “flow” when you’re on a roll, whether writing code, poetry, or prose, but because the learning curve is so steep for a text editor, it’s very easy to retain habits from your time learning the editor that stick with you well into mastery. Because Vim makes you so fast and fluent, it’s especially hard to root these out because you might not even notice them, but it’s worth it. Here I’ll list some of the more common ones.
Markdown | Codecademy
Markdown is a lightweight markup language for creating formatted text using a plain-text editor.
