When dealing with memory in C defaulting to malloc or some opaque structure behind it is unless you just want to allocate and forget it for some one off program

When dealing with memory in C defaulting to malloc or some opaque structure behind it is unless you just want to allocate and forget it for some one off program that frees memory on proc exit seems bad to me now. For any kind of sophisticated system or module you almost always want to write your own variety of slab, arena, pool, bump whatever it may be allocator.