Backend

Validate config at startup, secrets in memory only. Never read config during requests, never store secrets in env vars. Use node-env-resolver for multi-source config.

Provides brutally honest, quick feedback on app ideas before investing time building. Use when the user presents an app idea, asks for validation of a concept, or before starting any new project. Evaluates market saturation, actual demand, solo-builder feasibility (2-4 weeks), monetization potential, and interest factor.

CRITICAL for ALL mathematical and numerical operations including arithmetic, percentages, averages, and DATE/CALENDAR calculations (day of week, date differences, time calculations). MANDATORY when user asks to calculate, compute, solve expressions, determine dates, or perform any numeric analysis.

Guide for creating high-quality MCP (Model Context Protocol) servers that enable LLMs to interact with external services through well-designed tools. Use when building MCP servers to integrate external APIs or services, whether in Python (FastMCP) or Node/TypeScript (MCP SDK).

Install Playwright MCP for browser automation. Use when user needs web testing/scraping capabilities.

Design and implement robust, production-grade backend systems with strong architecture, correctness, performance, and operational rigor. Use this skill when the user asks to build APIs, services, data pipelines, system architectures, or backend-heavy applications.

Personal project implementation and modification guide. Use when creating or modifying Python 3.13 personal projects with FastAPI/Typer, pyproject.toml, and uv package manager.

Configuring MCP Servers & Plugins for Claude Code. Set up Model Context Protocol servers (GitHub, Filesystem, Brave Search, SQLite). Configure OAuth, manage permissions, validate MCP structure. Use when integrating external tools, APIs, or expanding Claude Code capabilities.

Create and manage database migrations with reversible up/down methods, focused changes, and zero-downtime deployment considerations. Use this skill when creating or modifying migration files in directories like migrations/, db/migrate/, alembic/versions/, sequelize/migrations/, prisma/migrations/, or any database schema versioning folders. Use this when adding or altering database tables, columns, indexes, foreign keys, or constraints in migration scripts, implementing both up (apply changes) and down (rollback changes) methods for reversible migrations that allow safe rollbacks if deployments fail, writing migration scripts for ORMs and migration tools like Sequelize, Alembic, Django migrations, Rails migrations, TypeORM, Prisma migrations, Knex.js migrations, or any database migration framework, creating database indexes on large tables using concurrent creation options like CREATE INDEX CONCURRENTLY in PostgreSQL to avoid table locks that would block production traffic during deployment, separating schema

This skill should be used when the user uses ambiguous terminology like "make it talk", "we need an api", "make it portable", "check for gaps", asks meta-questions like "am I making sense?", "does this make sense?", mentions being a "non-technical user", uses vague action verbs ("make it work", "do the thing"), mixes domain languages, uses invented terms, or when detecting semantic drift between human natural language and technical precision. Provides semantic translation, disambiguation, and domain knowledge mapping across Autogen, Langroid, MCP (Model Context Protocol), UTCP (Universal Tool Calling Protocol), FastAPI, Git/Gitflow, SRE (Site Reliability Engineering), and Memory Graphs domains. Bridges the gap between user intent and technical specificity through ontological translation.

WHEN: Rust API review with Actix-web/Axum/Rocket, async patterns, extractors, middlewareWHAT: Async handlers + Extractors + State management + Error responses + Tower middlewareWHEN NOT: General Rust → rust-reviewer, Go API → go-api-reviewer

Systematic debugging workflow to reproduce, isolate, and fix hard software bugs, resolve related lint issues, and add tests and guardrails to prevent regressions. This skill should be used for complex bugs that teams struggle to fix, flaky/intermittent failures, production-only bugs, and environment-specific issues where code changes must be lint-clean.

Create Django REST Framework serializers with validation. Use when creating serializers, adding validation logic, handling request/response data, or transforming model data.

Model system responsibilities across clients, servers, and optional peer nodes.

Expert Python development including FastAPI, Django, data processing, async programming, and best practices

Use when fixing CJS/ESM module issues in Nango integrations after zero-yaml migration - covers import path fixes, creating ESM wrappers for CJS vendor modules, and restoring commented-out code

Integrates SonarQube for continuous code quality analysis. Configures server setup, GitHub Actions workflows, quality gates, and security scanning (SAST, DAST, SCA).

Expert code writer specializing in production-grade Python, FastAPI, and microservices development. Activated for writing clean, maintainable, well-tested code following best practices for the SaaS platform.

Your approach to handling backend providers. Use this skill when working on files where backend providers comes into play.

Multi-tier LLM routing for cost optimization in the BidDeed.AI ecosystem. Routes tasks to appropriate model tier based on complexity, achieving 40-55% FREE tier processing. Use when making API calls, selecting models, implementing chat interfaces, or optimizing AI costs. Tiers: FREE (gemini-2.5-flash 1M context), ULTRA_CHEAP (deepseek-v3.2), CHEAP, STANDARD, PREMIUM (claude-sonnet-4), ULTRA (claude-opus-4.5).