Developer Quick Reference Cheatsheets
High-density, production-tested cheat sheets for C#, Python, SQL, and Git. Bookmark these reference cards for immediate copy-paste solutions.
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Vibe Coding & AI IDEs Cheatsheet: .cursorrules, MCP & High-Leverage Prompts
The definitive 2026 reference for Vibe Coding. Production .cursorrules templates, Claude Code workflows, MCP tool definitions, and Ollama local model commands.
Python 3 Essential Quick Reference & Syntax Cheatsheet
Fast reference guide for Python lists, dictionaries, list comprehensions, slicing, decorators, file I/O, and modern pattern matching.
C# 13 & LINQ Performance Cheatsheet
Master C# Language Integrated Query (LINQ), deferred execution, async streams, records, and memory-efficient spans.
Git Essential Workflows & Undo Commands Cheatsheet
Quick reference for daily Git operations: branching, interactive rebasing, stash management, cherry-picking, and undoing commits.
SQL & Relational Database Indexing Cheatsheet
Practical SQL cheat sheet: joins, window functions (ROW_NUMBER, RANK), CTEs, and B-Tree indexing rules.
Modern JavaScript Cheatsheet: ES6+ Syntax, Array Methods, Async and Modules
Fast reference for modern JavaScript: let and const, destructuring, spread, template literals, the array methods that matter, async/await, modules and classes.
Docker Commands Cheatsheet: Images, Containers, Compose and Cleanup
The Docker commands used daily: build and manage images, run and debug containers, wire volumes and networks, drive Docker Compose, and clean up disk space safely.
FastAPI Cheatsheet: Routes, Parameters, Pydantic, Dependencies and Errors
FastAPI essentials in one page: routes for every HTTP method, typed parameters with validation, Pydantic request and response models, dependencies, routers and error handling.
React Hooks Cheatsheet: useState, useEffect, useRef, useMemo and useCallback
React hooks without the guesswork: useState and useEffect patterns, when refs beat state, useMemo and useCallback done right, context, reducers, and the rules of hooks.
TypeScript Cheatsheet: Types, Interfaces, Generics and Utility Types
TypeScript reference for working code: primitive and union types, interfaces vs type aliases, generics with constraints, and the utility types you will actually use.
n8n Automation Cheatsheet: Core Nodes, Expressions, Credentials and Error Workflows
n8n quick reference: the core nodes that appear in every workflow, expression syntax with {{ }}, how data and credentials flow, and the error-handling setup that keeps automations alive.
Prompt Engineering Cheatsheet: Patterns for Coding and Research Agents
Prompt patterns that reliably work on AI agents: the anatomy of a strong prompt, coding-agent patterns (scope, tests, diffs), research patterns (sources, structure, verification), and copy-ready templates.