Backend

A reference skill providing PostgreSQL best practices covering query optimization, schema design, indexing strategies, Row Level Security, and connection pooling. Based on Supabase guidelines, it serves as a quick lookup for common patterns like composite indexes, cursor pagination, and queue processing.

A reference guide for backend development patterns including RESTful API design, repository and service layer patterns, database query optimization, caching strategies, authentication/authorization, rate limiting, and error handling. Contains TypeScript code examples for Node.js and Next.js applications.

A comprehensive guide for implementing saga patterns in distributed systems. Provides Python templates for orchestration-based and choreography-based sagas, including order fulfillment workflows, compensation handling, and timeout management.

A comprehensive reference guide for designing durable workflows with Temporal. Covers workflow vs activity separation, saga patterns for distributed transactions, state management, determinism constraints, and best practices for building reliable long-running processes and microservice orchestration.

This skill provides comprehensive guidance for implementing Stripe payment processing in web applications. It covers one-time payments, subscription billing, webhook handling, customer management, and refund processing with PCI-compliant patterns.

A comprehensive reference skill for designing microservices architectures. It covers service decomposition strategies, synchronous and asynchronous communication patterns, distributed data management with sagas, and resilience patterns like circuit breakers. All content is educational documentation with Python code examples.

This skill provides comprehensive guidance for creating distributable Python packages. It covers project structure patterns, pyproject.toml configuration, CLI tool creation with Click or argparse, building wheels and source distributions, and publishing to PyPI with proper versioning and CI/CD automation.

A comprehensive guide for integrating PayPal payments into applications. Covers Express Checkout with Smart Payment Buttons, IPN (Instant Payment Notification) webhook handling, recurring billing/subscriptions, and refund workflows with Python and JavaScript examples.

This skill helps developers create and maintain OpenAPI 3.1 specifications for RESTful APIs. It provides comprehensive templates for design-first and code-first approaches, including Python/FastAPI and TypeScript/tsoa examples, along with validation tooling configuration and SDK generation commands.

A comprehensive guide for designing REST and GraphQL APIs with best practices. Includes production-ready FastAPI templates, GraphQL schema patterns, pagination strategies, error handling conventions, and detailed checklists for pre-implementation review.

A comprehensive reference guide for implementing authentication and authorization systems. Covers JWT tokens, OAuth2/social login, session management, role-based access control (RBAC), and security best practices with TypeScript/Express code examples.

This skill provides comprehensive PostgreSQL database design guidance covering data types, indexing strategies, constraints, partitioning, and schema design patterns. It includes detailed recommendations for handling JSONB, time-series data, update-heavy tables, and safe schema evolution practices.

A comprehensive guide for implementing automated billing systems including SaaS subscription management, recurring payments, invoice generation, and failed payment recovery (dunning). Provides Python code examples for integration with payment processors like Stripe.

A comprehensive reference skill for building production-ready Node.js backend applications. It provides architectural patterns, code templates, and best practices for Express.js and Fastify frameworks, covering authentication, database integration, middleware, error handling, and caching strategies.

A comprehensive reference guide for Python asynchronous programming. Covers asyncio fundamentals, coroutines, tasks, async context managers, producer-consumer patterns, rate limiting with semaphores, and real-world examples including web scraping with aiohttp, async database operations, and WebSocket servers.

A comprehensive guide to proven backend architecture patterns. Teaches Clean Architecture (Uncle Bob's layers), Hexagonal Architecture (Ports and Adapters), and Domain-Driven Design (DDD) tactical patterns with Python code examples for building maintainable, testable, and scalable systems.

This skill provides comprehensive guidance for executing database migrations across popular ORMs including Sequelize, TypeORM, and Prisma. It covers schema transformations, data migrations, rollback procedures, and zero-downtime deployment strategies with practical code examples.

This skill provides production-ready FastAPI project templates with comprehensive patterns for async database operations, CRUD repositories, service layers, JWT authentication, and testing. It guides developers in setting up well-structured Python API projects using modern async patterns and best practices.

This skill provides comprehensive guidance for implementing NFT standards in Solidity. It covers ERC-721 and ERC-1155 token contracts, metadata best practices (on-chain and IPFS), royalty implementation (EIP-2981), soulbound tokens, dynamic NFTs, and gas-optimized minting with ERC721A.

This skill teaches SQL optimization techniques including query execution plan analysis (EXPLAIN), indexing strategies (B-Tree, GIN, GiST, BRIN), and common optimization patterns. It covers eliminating N+1 queries, cursor-based pagination, aggregate optimization, materialized views, and table partitioning for PostgreSQL and MySQL databases.

This skill provides extensive patterns and best practices for authentication implementation (JWT, OAuth2, sessions), monorepo management (Turborepo, Nx, Bazel), debugging strategies, E2E testing with Playwright/Cypress, error handling, Git workflows, and code review excellence. It serves as a reference guide for building secure, scalable applications.

This skill collection provides expert assistance for modern Python development. It includes specialized agents for Django, FastAPI, and general Python development, along with comprehensive documentation for async programming patterns, Python packaging with pyproject.toml, performance profiling and optimization, pytest testing strategies, and the fast uv package manager.

This skill provides comprehensive guidance for implementing billing automation systems including subscription management, dunning workflows, and payment processing. It covers Stripe and PayPal integrations with PCI-compliant patterns, webhook handling, proration calculations, and tax management for SaaS billing.

This skill provides production-ready Solidity smart contract templates for building DeFi applications including staking platforms, automated market makers (AMMs), governance systems, flash loans, and NFT standards. It includes comprehensive security best practices, vulnerability prevention patterns, and testing strategies using Hardhat and Foundry.

A comprehensive FastAPI project template skill that provides production-ready project structures, async patterns, dependency injection examples, and best practices for building high-performance Python APIs. Includes guidance for Django, GraphQL, and general backend architecture.

A comprehensive PostgreSQL database design guide that covers data types, indexing strategies, constraints, partitioning, JSONB usage, and performance optimization patterns. Includes AI agent definitions for database architecture and SQL expertise to help design scalable, maintainable database schemas.

This skill provides comprehensive backend development guidance covering REST and GraphQL API design principles, microservices architecture patterns, CQRS implementation, event sourcing with projections, saga orchestration for distributed transactions, and Temporal workflow patterns with Python SDK. It includes production-ready templates, testing strategies, and best practices for building scalable distributed systems.

Implement DeFi protocols with production-ready templates for staking, AMMs, governance, and lending systems. Use when building decentralized finance applications or smart contract protocols.

A comprehensive Ruby on Rails style guide based on DHH and 37signals conventions. It provides detailed patterns for controllers, models, frontend (Turbo/Stimulus), architecture, testing (Minitest/fixtures), and gem selection following the 'vanilla Rails is plenty' philosophy.

A comprehensive guide for writing Ruby gems following Andrew Kane's battle-tested patterns from gems like Searchkick, PgHero, and Chartkick. Covers entry point structure, Rails integration with ActiveSupport.on_load, class macro DSLs, database adapter patterns, Minitest testing, and gemspec best practices.