developwith

Language guides, LeetCode solutions, and architecture patterns — organized and practical.

Learn a Language

Step-by-step progressions from basics to mastery.

Ruby

Dynamic, expressive scripting for web APIs and devops.

6 steps

Python

Readable, versatile — from scripting to data science.

6 steps

Go

Fast, concurrent, opinionated — built for infrastructure.

6 steps

TypeScript

Typed JavaScript for scalable front-end and back-end.

6 steps

LeetCode Study Guide

Problems and solutions across Ruby, Python, Go, TypeScript, and Elixir.

All Problems →

Browse the full problem set with solutions in each language.

algorithms · data structures

Cheatsheets

Quick reference for structures, functions, loops, and concurrency.

Ruby

Arrays, hashes, blocks, threads, and more.

quick reference

Python

Lists, dicts, comprehensions, asyncio, and more.

quick reference

Go

Slices, maps, goroutines, channels, and more.

quick reference

TypeScript

Arrays, maps, async/await, generics, and more.

quick reference

Elixir

Lists, maps, pattern matching, actors, and more.

quick reference

Comparisons

Side-by-side language comparisons — syntax, idioms, and trade-offs.

Go vs Ruby

Static vs dynamic, goroutines vs threads, explicit errors vs exceptions.

comparison

Ruby vs Elixir

Object-oriented vs functional, threads vs actor model, GIL vs BEAM.

comparison

Ruby vs Python

Expressiveness vs readability, blocks vs comprehensions, Rails vs Django.

comparison

Python vs Ruby

One-obvious-way vs principle-of-least-surprise, data science vs web frameworks.

comparison

Architecture

Patterns, case studies, and technology decisions.

Architecture Guide →

Design patterns, system design, and trade-offs.

patterns · case studies

How-To

Practical solutions to specific problems.

Ruby

How to solve different problems with Ruby.

18 articles

Kotlin

Practical Kotlin tips and solutions.

6 articles

Java

How use Java for various projects.

8 articles

Unix

How to do various tricks in unix/linux.

3 articles

Databases

How to setup, manage and interact with various databases.

5 articles

Git

How to use distributed version control such as git.

3 articles

AI

Artificial intelligence and machine learning how-tos.

2 articles

Architecture

How to design software and when to use what technology.

1 articles

Mac

How to do various tricks in macOS.

2 articles