It’s a ‘minimal’ allocator. Reading the blog it seems to be going in depth into allocator principles, in practice, things like coalescing blocks.

I haven’t read in full so not sure if it discusses using blocks vs other structures (eg stack-based allocators, stack being the data structure not the program stack.) Ie, it’s a set of implementation choices. It still seems to reflect common ways of allocating in far more detail than many blogs I’ve read on the topic do.