development & code tools

the strongest category. these actually change your workflow.

must-install

webapp-testing — Playwright-based web app testing. official Anthropic skill. see official.
test-driven-development — enforces TDD: write tests before implementation, 85-95% coverage targets. from obra/superpowers.
Playwright Browser Automation (2.4k stars) — model-invoked Playwright for general browser automation. by @lackeyjb
systematic-debugging — structured debugging methodology. from obra/superpowers.

finishing-a-development-branch — guides branch completion with clear workflow options. obra/superpowers.
using-git-worktrees — isolated worktrees with smart directory selection. obra/superpowers.
Changelog Generator — transforms git commits into user-facing release notes.

software-architecture — Clean Architecture, SOLID principles. from NeoLab's context-engineering-kit.
subagent-driven-development — dispatches subagents with code review checkpoints.
adversarial-spec (523 stars) — iteratively refines specs by debating between multiple LLMs.
cc-sdd (3.1k stars) — spec-driven development, Kiro-style commands.

planning-with-files (18.5k stars) — Manus-style persistent markdown planning. widely adopted.
deep-research — autonomous multi-step research via Gemini Deep Research Agent. see also data-and-analysis.
last30days (20.7k stars) — researches any topic across Reddit, X, YouTube, HN, Polymarket, web. was #1 trending on GitHub. see also communication-and-writing.

requesting-code-review / receiving-code-review — two-stage code review process. obra/superpowers.
claude-review-loop (641 stars) — automated code review loop with Codex.
verification-before-completion — prevents premature task completion. obra/superpowers.

aws-skills — AWS CDK best practices, serverless, cost optimization.
iOS Simulator — Claude interacts with iOS Simulator. by @conorluddy
Axiom (810 stars) — battle-tested iOS/iPadOS/watchOS/tvOS development.
SwiftUI-Agent-Skill (3.5k stars) — SwiftUI best practices. by Paul Hudson (Hacking with Swift).
dotnet-skills (767 stars) — skills for .NET developers.
godogen (2.8k stars) — builds complete Godot 4 projects from a game description.
webgpu-claude-skill (591 stars) — WebGPU development with Three.js.

dev-browser (5.7k stars) — gives agents web browsing ability.
agent-sandbox-skill — isolated E2B cloud sandbox for dev without touching local filesystem.
browserwing (1.2k stars) — turns browser actions into MCP commands or Claude Skills.

Claude Code Terminal Title — dynamic terminal titles describing current work.
skill-codex (1.1k stars) — delegates prompts from Claude to Codex.
jules — delegate to Google Jules for async GitHub work. by @sanjay3290
cartographer (540 stars) — maps codebases using parallel AI subagents.
codebase-to-course (3.4k stars) — converts any codebase into an interactive HTML course.

see frameworks for the full breakdown of multi-skill systems (obra/superpowers, NeoLab, etc.)

also see: addyosmani/agent-skills (12.8k stars) — production-grade engineering skills from Addy Osmani (Google Chrome team).