Software Engineering Skills
Browse 1,059 curated software engineering skills for Claude Code, Cursor, and Codex. License-verified, MCP-ready, free to start.
Supabase Node
Express/Hono with Supabase and Drizzle ORM
Supabase Postgres Best Practices
Postgres performance optimization and best practices from Supabase. Use this skill when writing, reviewing, or optimizing Postgres queries, schema designs, or database configurations.
Supabase Python
FastAPI with Supabase and SQLAlchemy/SQLModel
Svelte 5 and SvelteKit Development Instructions
Svelte 5 and SvelteKit development standards and best practices for component-based user interfaces and full-stack applications
Svm
Explore Solana's architecture and protocol internals. Covers the SVM execution engine, account model, consensus, transactions, validator economics, data layer, development tooling, and token extensions using the Helius blog, SIMDs, and Agave/Firedancer source code.
Sweep
Detecting unnecessary files, unused code, and orphaned files, and proposing safe deletion. For repo cleanup, dead code removal, or tidying. Don't use for removal execution (Builder), deletion review (Judge), repo structure (Grove), or scope cutting (Void).
Swift MCP Expert
Expert assistance for building Model Context Protocol servers in Swift using modern concurrency features and the official MCP Swift SDK.
Swift MCP Server Development Guidelines
Best practices and patterns for building Model Context Protocol (MCP) servers in Swift using the official MCP Swift SDK package.
SwiftUI Expert Skill
Use when writing, reviewing, or refactoring SwiftUI code for iOS or macOS, including state management and `@Observable` data flow, view composition and invalidation/performance, lists and `ForEach` identity, environment usage, localization, animations, Liquid Glass adoption, migrating soft-deprecated APIs, or Instruments `.trace` capture/analysis for hangs, hitches, CPU hotspots, or excessive view updates.
Symfony Development Instructions
Symfony development standards aligned with official Symfony Best Practices
Systematic Debugging
Root-cause route for actual bugs, failing tests, build errors, crashes, stack traces, and unexpected behavior. Do not use for test-first/TDD feature work, test-report packaging, review-feedback handling, or final completion evidence.
Systematic Debugging
Find the root cause of bugs using the scientific method — form hypotheses, test them, narrow the search space. Not guessing, not random prints.
Systematic Debugging
4-phase root cause debugging: understand bugs before fixing.
Systematic Debugging
Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes
System Profile
Profile a target (script, process, GPU, memory, interconnect) for performance analysis. Use when user says "profile", "benchmark", "bottleneck", or wants performance analysis.
Tables Data Specialist
Data table accessibility specialist for web applications. Use when building or reviewing any data table, sortable table, grid, spreadsheet-like interface, comparison table, pricing table, or any tabular data display. Covers proper markup, scope, caption, headers, sortable columns, responsive patterns, and ARIA grid/treegrid roles. Applies to any web framework or vanilla HTML/CSS/JS.
Tailwind CSS v4+ Installation with Vite
Tailwind CSS v4+ installation and configuration for Vite projects using the official @tailwindcss/vite plugin
Tailwind Design System
Build scalable design systems with Tailwind CSS v4, design tokens, component libraries, and responsive patterns. Use when creating component libraries, implementing design systems, or standardizing UI patterns.
TanStack Start with Shadcn/ui Development Guide
Guidelines for building TanStack Start applications
Task Coordination Strategies
Decompose complex tasks, design dependency graphs, and coordinate multi-agent work with proper task descriptions and workload balancing. Use this skill when breaking down work for agent teams, managing task dependencies, or monitoring team progress.
Task Plan Implementation Instructions
Instructions for implementing task plans with progressive tracking and change record - Brought to you by microsoft/edge-ai
Tdd
Test-driven development. Use when the user wants to build features or fix bugs test-first, mentions "red-green-refactor", or wants integration tests.
TDD Green Phase - Make Tests Pass Quickly
Implement minimal code to satisfy GitHub issue requirements and make failing tests pass without over-engineering.
Tdd Guide
Test-first development route for TDD, writing failing tests first, RED -> GREEN -> REFACTOR, and behavior-changing feature/bug/refactor work. Do not use for already-failing test root-cause debugging, test-report packaging, or final completion evidence.
TDD Red Phase - Write Failing Tests First
Guide test-first development by writing failing tests that describe desired behaviour from GitHub issue context before implementation exists.
TDD Refactor Phase - Improve Quality & Security
Improve code quality, apply security best practices, and enhance design whilst maintaining green tests and GitHub issue compliance.
Team Coordination
Multi-person projects - shared state, todo claiming, handoffs
Technical Debt Remediation Plan
Generate technical debt remediation plans for code, tests, and documentation.
Technology Stack Blueprint Generator
Comprehensive technology stack blueprint generator that analyzes codebases to create detailed architectural documentation. Automatically detects technology stacks, programming languages, and implementation patterns across multiple platforms (.NET, Java, JavaScript, React, Python). Generates configurable blueprints with version information, licensing details, usage patterns, coding conventions, and visual diagrams. Provides implementation-ready templates and maintains architectural consistency for guided development.
Telegram Bot
Telegram bot development - chatbots, notifications, AI assistants, and group automation
Template Builder
Interactive guided wizard for creating GitHub issue templates, PR templates, and discussion templates. Answer simple questions and get production-ready YAML templates -- no manual YAML writing required.
Tempo
Designing scheduling and time-aware logic for cron, timezone/DST, retry/backoff, and business-calendar systems. Use when schedule design is needed.
Temporal Python Testing
Test Temporal workflows with pytest, time-skipping, and mocking strategies. Covers unit testing, integration testing, replay testing, and local development setup. Use when implementing Temporal workflow tests or debugging test failures.
Temporary ID Safe Output
Add temporary ID support to safe-output jobs end to end.
Terminal Helper
Fast terminal syntax and command helper for PowerShell and Bash
Terraform Style Guide
Generate Terraform HCL code following HashiCorp's official style conventions and best practices. Use when writing, reviewing, or generating Terraform configurations.
Terraform Test
Comprehensive guide for writing and running Terraform tests. Use when creating test files (.tftest.hcl), writing test scenarios with run blocks, validating infrastructure behavior with assertions, mocking providers and data sources, testing module outputs and resource configurations, or troubleshooting Terraform test syntax and execution.
Testcafe Skill
Generates TestCafe automation tests in JavaScript or TypeScript. Supports local and TestMu AI cloud. Triggers on: "TestCafe", "test cafe", "fixture/test".
Testcontainers Dotnet
A comprehensive guide for using Testcontainers for .NET (4.10.0+) to write reliable integration tests with Docker containers in .NET projects. Supports 65+ pre-configured modules for databases, message queues, cloud services, and more.
Testcontainers Go
A comprehensive guide for using Testcontainers for Go to write reliable integration tests with Docker containers in Go projects. Supports 62+ pre-configured modules for databases, message queues, cloud services, and more. Use this skill when writing Go integration tests, setting up test databases (PostgreSQL, MySQL, Redis, MongoDB), testing with message queues (Kafka, RabbitMQ), or creating container-based test infrastructure. Covers modules, generic containers, networking, cleanup, wait strategies, CI/CD integration, and common anti-patterns.
Test Driven Development
Drives development with tests. Use when implementing any logic, fixing any bug, or changing any behavior. Use when you need to prove that code works, when a bug report arrives, or when you're about to modify existing functionality.
Test Driven Development
Use when implementing any feature or bugfix, before writing implementation code
Test Driven Development
TDD: enforce RED-GREEN-REFACTOR, tests before code.
Test Fixing
Run tests and systematically fix all failing tests using smart error grouping. Use when user asks to fix failing tests, mentions test failures, runs test suite and failures occur, or requests to make tests pass.
Test Framework Migration Skill
Migrates and converts test automation scripts between Selenium, Playwright, Puppeteer, and Cypress. Use when the user asks to migrate, convert, or port tests from one framework to another; rewrite tests in a different framework; or switch from Selenium to Playwright, Playwright to Selenium, Puppeteer to Playwright, Cypress to Playwright, or vice versa. Triggers on: "migrate", "convert", "port", "selenium to playwright", "playwright to selenium", "puppeteer to playwright", "cypress to playwright", "rewrite tests in", "switch from [framework] to [framework]".
Testing Coach
Accessibility testing coach for web applications. Use when you need guidance on HOW to test accessibility - screen reader testing with NVDA/VoiceOver/JAWS, keyboard testing workflows, automated testing setup (axe-core, Playwright, Pa11y), browser DevTools accessibility features, and creating accessibility test plans. Does not write product code - teaches and guides testing practices.
Test Master
Generates test files, creates mocking strategies, analyzes code coverage, designs test architectures, and produces test plans and defect reports across functional, performance, and security testing disciplines. Use when writing unit tests, integration tests, or E2E tests; creating test strategies or automation frameworks; analyzing coverage gaps; performance testing with k6 or Artillery; security testing with OWASP methods; debugging flaky tests; or working on QA, regression, test automation, quality gates, shift-left testing, or test maintenance.
Testng Skill
Generates TestNG tests in Java with groups, data providers, parallel execution, XML suite configuration, and listeners. Use when user mentions "TestNG", "@DataProvider", "testng.xml", "groups". Triggers on: "TestNG", "@DataProvider", "testng.xml", "TestNG suite", "parallel tests Java".
Test Scenarios
Create comprehensive test scenarios from user stories with test objectives, starting conditions, user roles, step-by-step actions, and expected outcomes. Use when writing QA test cases, creating test plans, defining acceptance tests, or preparing for feature validation.
Testunit Skill
Generates Test::Unit tests in Ruby. Classic xUnit-style testing with assert methods and test case classes. Use when user mentions "Test::Unit", "assert_equal Ruby", "Ruby test-unit". Triggers on: "Test::Unit", "Ruby test-unit", "assert_equal Ruby" (not RSpec).
Text Quality Reviewer
Non-visual text quality reviewer for web applications. Use when reviewing any page, component, or template for low-quality alt text, aria-labels, or button names. Detects template variables ({0}, {{var}}), code syntax in text attributes (property.alttext), placeholder text as labels, typos in short accessible names, whitespace-only names, and duplicate control labels. Enforces WCAG 1.1.1 (Non-text Content), 4.1.2 (Name, Role, Value), and 2.5.3 (Label in Name). Applies to any web framework or vanilla HTML/CSS/JS.
Ticket Craft
Create Jira/Asana/Linear tickets optimized for Claude Code execution - AI-native ticket writing
Tmux
Control tmux sessions/panes for interactive CLIs: list, capture output, send keys, paste text, monitor prompts.
To Issues
Break a plan, spec, or PRD into independently-grabbable issues on the project issue tracker using tracer-bullet vertical slices.
Tool Design for Agents
Design every tool as a contract between a deterministic system and a non-deterministic agent. Unlike human-facing APIs, agent-facing tools must make the contract unambiguous through the description alone: agents infer intent from descriptions and generate calls that must match expected formats. Every ambiguity becomes a potential failure mode that no amount of prompt engineering can fix.
To Prd
Turn the current conversation into a PRD and publish it to the project issue tracker — no interview, just synthesis of what you've already discussed.
Track Management
Use this skill when creating, managing, or working with Conductor tracks - the logical work units for features, bugs, and refactors. Applies to spec.md, plan.md, and track lifecycle operations.
Trail
Investigating git history, analyzing regression root causes, and performing code archaeology. Time-travels through commit history to uncover truth. Use when git history investigation or regression analysis is needed.
Triage
Move issues and external PRs through a state machine of triage roles — categorise, verify, grill if needed, and write agent-ready briefs.
Troubleshoot
Systematic debugging with 5-step loop for issues in spaces/[project]/. Use when encountering bugs, test failures, or unexpected behavior.
Turborepo Caching
Configure Turborepo for efficient monorepo builds with local and remote caching. Use when setting up Turborepo, optimizing build pipelines, or implementing distributed caching.
Typescript
TypeScript strict patterns and best practices. Trigger: When writing TypeScript code - types, interfaces, generics.
Typescript
TypeScript strict mode with eslint and jest
Typescript Magician
Designs complex generic types, refactors `any` types to strict alternatives, creates type guards and utility types, and resolves TypeScript compiler errors. Use when the user asks about TypeScript (TS) types, generics, type inference, type guards, removing `any` types, strict typing, type errors, `infer`, `extends`, conditional types, mapped types, template literal types, branded/opaque types, or utility types like `Partial`, `Record`, `ReturnType`, and `Awaited`.
TypeScript MCP Server Development
Instructions for building Model Context Protocol (MCP) servers using the TypeScript SDK
Typescript MCP Server Generator
Generate a complete MCP server project in TypeScript with tools, resources, and proper configuration
Typescript Pro
Implements advanced TypeScript type systems, creates custom type guards, utility types, and branded types, and configures tRPC for end-to-end type safety. Use when building TypeScript applications requiring advanced generics, conditional or mapped types, discriminated unions, monorepo setup, or full-stack type safety with tRPC.
Typespec API Operations
Add GET, POST, PATCH, and DELETE operations to a TypeSpec API plugin with proper routing, parameters, and adaptive cards
Typing Exclusion Worker
Python typing exclusion worker: remove assigned mypy exclusion modules in small scoped batches, fix typing issues, run validation, and produce a structured completion summary. Use when running parallel typing-debt workers or when asked to remove modules from pyproject mypy exclusion overrides.
UI Test
AI-powered adversarial UI testing via the browse CLI. Analyzes git diffs to test only what changed, or explores the full app to find bugs. Tests functional correctness, accessibility, responsive layout, and UX heuristics. Use when the user asks to test UI changes, QA a pull request, audit accessibility, or run exploratory testing. Supports local browser (localhost) and remote Browserbase (deployed sites).
UI Testing
Visual testing - catch invisible buttons, broken layouts, contrast
UI Web
Web UI - glassmorphism, Tailwind, dark mode, accessibility
Understand
Analyze a codebase to produce an interactive knowledge graph for understanding architecture, components, and relationships
Understand Diff
Use when you need to analyze git diffs or pull requests to understand what changed, affected components, and risks
Understand Domain
Extract business domain knowledge from a codebase and generate an interactive domain flow graph. Works standalone (lightweight scan) or derives from an existing /understand knowledge graph.
Understand Explain
Use when you need a deep-dive explanation of a specific file, function, or module in the codebase
Understanding Stability Inference
Use this skill to explain why the Compose compiler classified a class or composable parameter as stable, runtime, unknown, or unstable. Covers the 12-phase inference algorithm, the five compiler-level stability types (Certain / Runtime / Unknown / Parameter / Combined), the generic bitmask encoding (Pair=0b11, ImmutableList=0b1), the Known Stable Constructs registry, and the runtime `$stable: Int` field generated by `@StabilityInferred`. Use when the developer asks "why is X classified as Y?", when a stability report shows a surprising `runtime stable`, `unknown`, or `unstable` verdict, when generics, inheritance, cycles, interfaces, or cross-module classes are involved, or when the user mentions `$stable`, `@StabilityInferred`, separate compilation, or "the compiler thinks my class is unstable but it looks fine".
Understand Onboard
Use when you need to generate an onboarding guide for new team members joining a project
Unit Test Vue Pinia
Write and review unit tests for Vue 3 + TypeScript + Vitest + Pinia codebases. Use when creating or updating tests for components, composables, and stores; mocking Pinia with createTestingPinia; applying Vue Test Utils patterns; and enforcing black-box assertions over implementation details.
Universal Janitor
Perform janitorial tasks on any codebase including cleanup, simplification, and tech debt remediation.
Universal PR Comment Addresser
Address PR comments
Unslop Commit
Rewrites commit messages so they sound like a careful human engineer wrote them. Strips AI/marketing slop ("comprehensive solution", "robust implementation", "leverage", "enhance", "seamlessly", "This commit..."). Keeps Conventional Commits format. Subject ≤72 chars (aim ≤50), imperative mood. Body only when "why" isn't obvious from the subject. Use when user says "humanize commit", "de-slop commit message", "make this commit sound human", "/unslop-commit", "/commit", "write a commit", or pastes a draft commit to clean up. Auto-triggers when staging changes.
Unslop Review
Rewrites code review comments so they read like a human teammate wrote them. Cuts corporate-AI throat-clearing ("I noticed...", "I was wondering if perhaps...", "It might be worth considering..."). Each comment is direct: location, the issue, a concrete fix. Use when user says "humanize review", "de-slop PR comment", "make this feedback sound human", "review this PR", "code review", "/review", "/unslop-review". Auto-triggers when reviewing PRs.
Update Code from Shorthand
Shorthand code will be in the file provided from the prompt or raw data in the prompt, and will be used to update the code file when the prompt has the text `UPDATE CODE FROM SHORTHAND`.
Update Implementation Plan
Update an existing implementation plan file with new or update requirements to provide new features, refactoring existing code or upgrading packages, design, architecture or infrastructure.
Update LLMs
Update the llms.txt file in the root folder to reflect changes in documentation or specifications following the llms.txt specification at https://llmstxt.org/
Update Markdown File Index
Update a markdown file section with an index/table of files from a specified folder.
Update Specification
Update an existing specification file for the solution, optimized for Generative AI consumption based on new requirements or updates to any existing code.
Update SwiftUI Apis
Scan Apple's SwiftUI documentation for deprecated APIs and update the SwiftUI Expert Skill with modern replacements. Use when asked to "update latest APIs", "refresh deprecated SwiftUI APIs", "check for new SwiftUI deprecations", "scan for API changes", or after a new iOS/Xcode release. Requires the Sosumi MCP to be available.
Using Git Worktrees
Git worktree management with tmux integration and task dispatch. Use when creating isolated dev environments, launching parallel feature work, running multiple Claude instances, managing worktrees, dispatching tasks to worktree terminals, or cleaning up after merge. Covers worktree creation in .claude/worktrees/, tmux window management in the current session, and command dispatch. Also use when someone says "create a worktree", "launch in a worktree", "worktree for story X", or "parallel development".
Using Git Worktrees
Use when starting feature work that needs isolation from current workspace or before executing implementation plans - ensures an isolated workspace exists via native tools or git worktree fallback
Using Stability Analyzer Ide Plugin
Use this skill to install and operate the `skydoves/compose-stability-analyzer` IntelliJ / Android Studio plugin so the developer sees Compose stability feedback live in the editor instead of waiting for a Gradle build. Covers installing the plugin from disk, configuring the `Settings → Tools → Compose Stability Analyzer` panel, reading the four gutter colors (green stable, red unstable, yellow runtime, gray no-params), the per-parameter hover documentation, the inline parameter hint badges, and the `UnstableComposable` weak-warning inspection with its `@Suppress("NonSkippableComposable")` and `@Suppress("ParamsComparedByRef")` quick fixes. Use when the user mentions gutter icons, inline hints, the stability inspection, the IDEA plugin, real-time stability feedback while editing, or asks why a composable is flagged as non-skippable in the editor.
Using Tmux For Interactive Commands
Use when you need to run interactive CLI tools (vim, git rebase -i, Python REPL, etc.) that require real-time input/output - provides tmux-based approach for controlling interactive sessions through detached sessions and send-keys
Utility Mermaid Diagrams
Teaches PMs to create syntactically valid mermaid diagrams by selecting the right diagram type for their communication need, following syntax validity rules, and validating before shipping. Covers all 15 mermaid diagram types with PM-relevant examples and a dual-lens navigation system.
Utility Pm Skill Builder
Guides contributors from a PM skill idea to a complete Skill Implementation Packet aligned with pm-skills conventions. Runs gap analysis, validates through a Why Gate, classifies by type and phase, generates draft files, and writes to a staging area for review before promotion.
Utility Pm Skill Iterate
Applies targeted improvements to an existing pm-skills skill based on feedback, validation reports, or convention changes. Reads current files, previews proposed changes, writes on confirmation, and suggests a version bump. Use when improving a skill after validation or feedback.
Utility Update Pm Skills
Checks for newer pm-skills releases, compares local vs. latest version, previews what would change, and updates local files after user confirmation. Generates a structured update report documenting changed files, new capabilities, and the value delta between versions. Use when you want to bring a local pm-skills installation up to date.
Uv
Guide for using uv - an extremely fast Python package and project manager written in Rust. Use when installing Python, managing virtual environments, adding dependencies, running scripts, building packages, or working with pyproject.toml. Replaces pip, pip-tools, pipx, poetry, pyenv, twine, and virtualenv.
Uv Package Manager
Master the uv package manager for fast Python dependency management, virtual environments, and modern Python project workflows. Use when setting up Python projects, managing dependencies, or optimizing Python development workflows with uv.
Validate Album
Validates album directory structure, file locations, and content integrity. Use before release or whenever the user wants to check an album's structural health.