Safe-by-construction, 100% Rust memory toolkit (no C/C++ libraries — no libnuma/mimalloc/jemalloc/snmalloc/tcmalloc): handle store (Region<T>) + drop-in #[global_allocator] (SeferMalloc) over one verified segment substrate. Up to ~18x faster than mimalloc on cached large alloc/free.

Allocation profiling for Rust. Counters, peak resident, and call-site grouping with inline backtrace capture. Zero external dependencies in the hot path. Lean dhat replacement targeting MSRV 1.75.