Internal Headers

• types.h: Defines the types of all internal mimalloc datastructures and configuration options.
• decl.h: Compiler attributes, assertions, initialization macros, and platform-specific declarations.
• bits.h: Architecture dependent type definitions, and bit operations.
• atomic.h: Portable atomic operations and locks.
• prim.h: Primitive and minimal portability API needed from a host system.
• track.h: Memory-tracking integration for Valgrind, AddressSanitizer, and Windows event tracing.
• qsbr.h: Quiescent-state based reclamation primitives (for runtime systems like CPython).
• internal.h: Deprecated: umbrella header for internal allocator declarations and utilities.

Source Headers

• alloc: Internal allocation, freeing, and page-management interfaces.
• arena: Arena management, slice allocation, and arena-backed page interfaces.
• heap: Heap, thread-local heap, subprocess, initialization, and page-map interfaces. Also contains heap/process.h which declares (almost) all static variables.
• prim: Higher-level OS memory operations and primitive thread-local access.
• profile: Sampled allocation, guarded allocation, and profiler interfaces.
• util: Runtime utilities, options, randomness, statistics, and dynamic thread-local interfaces.