Challenges

Algorithms & Parsing

A timed C challenge covering stream parsing, recursion, combinatorics, and search

Systems & Processes

A timed C challenge covering process pipelines, signals, and compact parsers

Network Systems

A single-task C challenge: build a non-blocking TCP server that relays messages between many simultaneous clients on the loopback interface, with zero memory or file-descriptor leaks

Grids & Simulation

A timed C challenge on parsing a 2D grid, dynamic programming over it, and running a cellular simulation

Pointers & Memory

A timed C challenge on reaching values through pointers, walking arrays inside their bounds, and owning every byte you allocate

C Language Core

A timed C challenge on integer types, conversions and overflow, then on modelling data with structs, unions and enums

Data Structures

A timed C challenge on walking and re-linking nodes, then on the stacks and trees that evaluators are built from

Sort & Search

A timed C challenge on the invariant a sort establishes, the bricks it is built from, what it costs, and sorting anything at all