📋 Cheat Sheets

Developer Cheat Sheets

Quick reference pages for interviews, code reviews and daily development. Bookmark them.

Java Collections Cheat Sheet

Quick reference for Java Collections — ArrayList, LinkedList, HashMap, TreeMap, ...

Java Streams API Cheat Sheet

Complete Java Streams cheat sheet — intermediate and terminal operations, collec...

Python Built-in Functions Cheat Sheet

Complete reference for Python built-in functions — type conversion, math, sequen...

SQL Joins Cheat Sheet

Visual reference for all SQL JOIN types — INNER, LEFT, RIGHT, FULL OUTER, CROSS ...

Docker Commands Cheat Sheet

Essential Docker commands reference — containers, images, volumes, networks, Doc...

JVM Memory Model Diagram

Visual diagram of JVM memory areas — Heap, Young/Old generation, Metaspace, Stac...

How HashMap Works Internally

Illustrated diagram of Java HashMap internals — hashing, bucket array, collision...

Microservices Architecture Diagram

Visual reference for microservices architecture — API gateway, services, message...

Pandas Cheat Sheet

Quick reference for Pandas — DataFrame creation, selection, filtering, groupby, ...