01Module 01 - CPython Internals OverviewCPython architecture, the GIL, memory management, bytecode, and the interpreter loop - understanding the Python runtime from the inside.02CPython ArchitectureThe CPython source tree, the main evaluation loop, and how Python executes a .py file from disk to output.03Python Objects Under the HoodPyObject layout, type objects, reference counting, small integer cache, string interning, and the cost of Python's dynamic type system.04The GIL ExplainedWhat the GIL is, why it exists, how it works in CPython 3.12+, its performance impact, and the Python 3.13 free-threaded mode.05Memory Management InternalsCPython's memory allocator layers, the pymalloc arena system, reference counting, cyclic GC generations, and how memory is actually freed.06Bytecode and the CompilerHow Python source becomes bytecode, the dis module, .pyc files, peephole optimisation, and writing a bytecode-level function.07CPython in Python 3.13Free-threaded Python, the specialising adaptive interpreter, immortal objects, sub-interpreters, and what changed in the 3.10–3.13 internals.
