10. Advanced Topics

Free-threaded CPython, immortal objects, per-interpreter GIL, JIT work, stable ABI design tradeoffs, import system edge cases, serialization internals, security boundaries, and future directions.

9 items

Chapter Title
92 Free-Threaded CPython
93 Immortal Objects
94 Per-Interpreter GIL
95 JIT Work in CPython
96 Stable ABI Design Tradeoffs
97 Import System Edge Cases
98 Serialization Internals
99 Security Boundaries
100 Future Directions
Deep Reads › CPython Internals › 10. Advanced Topics ›

92. Free-Threaded CPython

PEP 703 no-GIL build: per-object locking, biased reference counting, and the free-threaded evaluation loop.
cpython python internals concurrency
Deep Reads › CPython Internals › 10. Advanced Topics ›

93. Immortal Objects

PEP 683 immortal objects: _Py_IMMORTAL_REFCNT sentinel, zero-cost incref/decref, and implications for forks.
cpython python internals memory
Deep Reads › CPython Internals › 10. Advanced Topics ›

94. Per-Interpreter GIL

PEP 684 per-interpreter GIL: isolated interpreter state, shared-nothing model, and module isolation requirements.
cpython python internals concurrency
Deep Reads › CPython Internals › 10. Advanced Topics ›

95. JIT Work in CPython

CPython 3.13 copy-and-patch JIT: template JIT design, trace selection, and the roadmap toward full JIT compilation.
cpython python internals performance
Deep Reads › CPython Internals › 10. Advanced Topics ›

96. Stable ABI Design Tradeoffs

What breaking the stable ABI costs, historical breakages, versioning policy, and the tradeoff against new features.
cpython python internals c-api
Deep Reads › CPython Internals › 10. Advanced Topics ›

97. Import System Edge Cases

Circular import resolution, namespace package search order, zip imports, and __import__ hook edge cases.
cpython python internals
Deep Reads › CPython Internals › 10. Advanced Topics ›

98. Serialization Internals

pickle protocol versions, the __reduce__ / __reduce_ex__ protocol, marshal format, and shelve internals.
cpython python internals
Deep Reads › CPython Internals › 10. Advanced Topics ›

99. Security Boundaries

CPython security model: what is and is not sandboxed, restricted execution limits, and audit hook coverage.
cpython python internals
Deep Reads › CPython Internals › 10. Advanced Topics ›

100. Future Directions

Active PEPs, the free-threaded and JIT roadmaps, memory model work, and how to follow CPython development.
cpython python internals