O0 to Hero

See what your code becomes
Write a line of C and the assembly gcc makes from it appears right beside it, line for line, in matching colours. Change the C and watch the assembly change. Nothing is hidden: this is the real compiler, at -O0, where every variable keeps its own slot on the stack and every step shows.
Watch the machine move
Animated scenes show what the CPU and memory actually do: a value loaded into a register, a slot on the stack overwritten, a byte split into the two hex digits you read every day. Pause them, step them, replay them.
Play the bits
Falling Bytes. Numbers fall. Your eight home-row fingers are the eight bits of a byte. Build each number before it lands.

Syntax Sprint. Type real C and Intel-syntax assembly against the clock, from a semicolon to a whole function.

The board. A fictional computer, drawn the way a circuit board looks in a design tool. Each part of it is a game, starting at the network card where data comes in off the wire. More of the board opens as the game grows.

A course underneath
Lessons start from zero: what a program is, how source becomes something the machine runs, why memory is numbered bytes. Then C itself, with every new idea read back in x86-64 assembly. Real checks grade your code. A failed Submit costs nothing. Quiz cards you miss come back until you get them right.
In the Playtest
Act 0, The Machine: 19 lessons

Act 1, C Foundations: 40 lessons so far

Animated scenes of the CPU and memory

Falling Bytes and Syntax Sprint, with the board's first district on the way

Linux, including Steam Deck (a keyboard is needed). Windows is on the way.

Why -O0?
-O0 is the gcc flag that turns optimization off. The compiler then writes the most literal assembly it can, which makes it the easiest assembly in the world to read. It is also the slowest, which is a trade worth making while you learn. The hero part is up to you.