Coding skills for the age of AI agents
Code of the Day
Tools expire. Understanding doesn't. Learn the fundamentals that outlast any framework, then go deep on the languages you actually ship.
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Free Dives
Durable theory and mental models that apply across every language and domain.
Fundamentals
The durable core: how programs work, reading docs and source, systems thinking, and working well with AI coding agents.
Data Types & Type Systems
How compilers and runtimes use types to catch bugs before they become crashes — primitives, static vs dynamic, strong vs weak, generics, and more.
Computer Architecture
How a CPU actually executes your code — the fetch-decode-execute cycle, registers, the memory hierarchy, and why cache locality is the single biggest performance lever you control.
Operating Systems
What an operating system actually does — processes, threads, scheduling, virtual memory, context switching, and the system-call boundary between user code and the kernel.
Networking Fundamentals
How data moves across networks — the layered model, IP addressing, TCP vs UDP, the three-way handshake, HTTP/HTTPS, DNS resolution, and why TLS matters.
Database Internals
What happens inside a database engine — B-tree indexes, heap vs index scans, ACID guarantees, write-ahead logging, MVCC, and why SELECT * can be slow.
Languages
Pick a language and go deep — syntax, idioms, and the mental model that makes each one click.
Python
Syntax and idioms for one of the most readable languages — from values and control flow to comprehensions and decorators.
JavaScript / TS
The language of the web — values and binding, the event loop, and the type system that keeps larger codebases honest.
SQL
Query and shape data with standard SQL that runs on a real in-browser database — plus per-dialect appendices for where flavors differ.
Rust
Memory safety without a garbage collector — ownership, borrowing, traits, and fearless concurrency, from first program to async Tokio and the Cargo ecosystem.
Bash
The universal interface to computers and servers — from first commands to scripting, text processing, shell mastery, and automating CI pipelines.
Go
Simple, fast, and compiled — from zero values and multiple returns to interfaces, goroutines, and production HTTP services powering the modern cloud stack.
Subject Tracks
Theory and practicals focused on a specific specialty — build something real while learning how it works.
Data Science
Use Python to load, clean, and explore data — turning raw observations into answers with pandas and clear statistical thinking.
Game Dev
Build 2D games with Python and pygame — from your first window to a complete playable game with real-time input and collision.
Workflow
Scripting and automation to make repetitive work disappear — read files, wrangle data, and build small tools that save hours.
Utilities
Small programs that do one thing well and compose into larger workflows — from CLI design to packaging and publishing on PyPI.
CS Fundamentals
Algorithms, data structures, and problem-solving patterns that apply everywhere — the vocabulary every programmer shares.