Backend

DDDアーキテクチャでFastAPIのバックエンドを新規実装または既存コードベースをリファクタリングする際のガイド。レイヤー構成（domain/application/infrastructure/controller）、依存方向、責務境界、pydantic/sqlalchemy(sqlmodel)/alembic/pytestの前提、セッション管理（Dependsで1リクエスト1セッション、必要時UoW）を含む。

Implement n8n credential types including API key, OAuth2, and header-based authentication patterns. Use this skill when creating *.credentials.ts files, implementing ICredentialType interfaces, configuring OAuth2 flows, setting up credential testing, injecting authentication headers, or following credential security best practices. Apply when building any n8n node that requires API authentication, token management, or secure credential handling.

Write optimized and secure database queries using parameterized queries, eager loading, and proper indexing strategies. Use this skill when writing database queries, constructing SQL statements, using ORM query methods, implementing data fetching logic, preventing SQL injection attacks, optimizing query performance, avoiding N+1 query problems, selecting specific columns instead of all data, implementing transactions for related operations, setting query timeouts, caching expensive queries, or working with WHERE clauses, JOINs, and ORDER BY statements. Apply this skill when fetching data from databases, optimizing slow queries, refactoring data access code, or reviewing query security and performance.

Build robust backend systems with modern technologies (Node.js, Python, Go, Rust), frameworks (NestJS, FastAPI, Django), databases (PostgreSQL, MongoDB, Redis), APIs (REST, GraphQL, gRPC), authentication (OAuth 2.1, JWT), testing strategies, security best practices (OWASP Top 10), performance optimization, scalability patterns (microservices, caching, sharding), DevOps practices (Docker, Kubernetes, CI/CD), and monitoring. Use when designing APIs, implementing authentication, optimizing database queries, setting up CI/CD pipelines, handling security vulnerabilities, building microservices, or developing production-ready backend systems.

Ruby 3.3+ development specialist covering Rails 7.2, ActiveRecord, Hotwire/Turbo, and modern Ruby patterns. Use when developing Ruby APIs, web applications, or Rails projects.

Brutally honest pre-build reality check for app ideas. Evaluates market saturation, demand, feasibility, monetization, and interest factor to save you from building things nobody wants.

Document APIs comprehensively with signatures, parameters, return values, errors, and working code examples for developer reference

Generate a basic cleanup plan (keep/delete/archive/ask) from a filesystem snapshot; no filesystem changes. Input: env.file_cleanup_plan_request_v1, output: ds.file_cleanup_plan_v1.

Uses the Vibesafe MCP server to scan, compile, test, save, diff, and report status for Vibesafe units. Activate when the user asks to run vibesafe CLI commands (scan/compile/test/save/diff/status), regenerate code from specs, or inspect drift/checkpoints.

Use this skill whenever the user wants to harden security for Cloudflare Workers/Pages APIs (e.g. Hono + TypeScript), including WAF-style protections, rate limiting, IP restrictions, secrets handling, and secure headers.

Frappe server-side Python patterns for controllers, document events, whitelisted APIs, background jobs, and database operations. Use when writing controller logic, creating APIs, handling document events, or processing data on the server.

Executes database migrations using the postgres MCP server. Use when applying schema changes, running migrations, or updating database structure.

Use when building Python web APIs, database-backed applications, or backend services. Covers FastAPI, SQLAlchemy (async), PostgreSQL, Alembic migrations, and performance patterns. Triggers on API endpoint creation, database models, query optimization, or migration planning. Extends python-development skill.

ASGI server for Python web applications - Fast, production-ready server for async frameworks

Harness MCP (Model Context Protocol) server integration for AI-powered CD operations, pipeline management, Git repositories, pull requests, code review comments, and bidirectional Jira synchronization

Comprehensive Supabase expert with access to 2,616 official documentation files covering PostgreSQL database, authentication, real-time subscriptions, storage, edge functions, vector embeddings, and all platform features. Invoke when user mentions Supabase, PostgreSQL, database, auth, real-time, storage, edge functions, backend-as-a-service, or pgvector.

Master REST API design principles to build intuitive, scalable, and maintainable APIs. Applicable for designing new APIs, reviewing API specifications, or establishing API design standards in Java Spring projects.

Master aesthetics - philosophy of beauty, art, and aesthetic experience. Use for: beauty, art theory, taste, sublime, creativity. Triggers: 'beauty', 'beautiful', 'aesthetic', 'art', 'sublime', 'creativity', 'taste', 'artistic', 'expression', 'representation', 'aesthetic experience', 'aesthetic judgment', 'art definition', 'Kant aesthetics', 'formalism', 'expressionism'.

Next.js 15 App Router patterns for Server/Client Components, async params, layouts, route handlers, Server Actions, and data fetching. Use when creating routes, pages, layouts, API endpoints, or implementing form submissions with revalidation.

Design, implement, and debug a custom ChatKit backend in Python that powers the ChatKit UI without Agent Builder, using the OpenAI Agents SDK (and optionally Gemini via an OpenAI-compatible endpoint). Use this Skill whenever the user wants to run ChatKit on their own backend, connect it to agents, or integrate ChatKit with a Python web framework (FastAPI, Django, etc.).