NAND²

Build a computer from gates

NAND² is a PC circuit-building and programming game where you work up from a single NAND gate to a 16-bit CPU. You wire gates into logic components, then use those components to build larger systems. Each finished part is added to your palette, so you can use it as a building block in later levels. The game has 201 levels across six eras, and complex parts are built from parts you made earlier rather than supplied as black boxes.

From relays to processors

The early eras cover logic, selection and binary numbers, followed by memory, clocks, an ALU, RAM and a Turing machine. Later, you build a processor, write programs, add I/O ports and create your own instructions. Levels also cover stacks, algorithms, robots and a RISC-V-style core.