TL;DR: A minimal memory allocator written in C as a learning exercise.
I was familiar with the basics but was in the dark about how memory allocators work under the hood, so I decided to write my own. Mini Malloc is a from-scratch mini_malloc / mini_free written in C, roughly implemented the way a real allocator would be.
The project follows a test-first structure. Claude wrote the test suite (a hand-rolled harness with a small ASSERT macro); I wrote the full implementation. The tests gate progress: the allocator starts as a stub, and the workflow is to work through a roadmap, making one test pass at a time until make test reports zero failures. Each test file covers a single concern, so the allocator grows in coherent layers rather than all at once.
The public API is just the two functions every allocator needs: mini_malloc(size) and mini_free(ptr). Because the implementation is linked with a name remap, it can optionally stand in for libc's malloc and free, which makes it possible to run real programs against it and catch bugs a unit test would miss.