Summary

• add a shared native C++ implementation for Windows and Linux
• expose a stable C ABI and an idiomatic C++ RAII API
• add Python bindings and platform wheels that bundle the native library
• preserve exact layout v1.2 interoperability with the existing .NET implementation
• add protocol fixtures, C++ and Python samples, packaging checks, CI jobs, and cross-runtime agents
• document lifecycle, recovery, diagnostics, portability, packaging, and release expectations

Motivation

SharedMemoryStore previously exposed only the managed implementation. Keeping the C++, Python, and .NET implementations in one repository lets them share a versioned protocol contract, fixtures, and interoperability gates, reducing the risk of layout or lifecycle drift.

User and developer impact

C#, C++, and Python processes can now exchange values through the same shared-memory store on Windows and Linux. Native consumers can use either the C ABI or the CMake-exported C++ API, while Python consumers receive a normal wheel with no runtime compiler requirement.

Platform-specific mapping, locking, and packaging concerns remain behind stable protocol and ABI boundaries. Existing managed API behavior remains compatible.

Validation

• 226 .NET unit, contract, integration, and interoperability tests
• Windows and Linux native CTest suites
• Linux ASan/UBSan native test run
• Python source and installed-wheel test suites
• all nine ordered C# / C++ / Python runtime pairings
• 1,000-value ordered-pair stress runs and 10,000 mixed-runtime cycles
• Windows and Linux Docker validation
• clean CMake and wheel consumer tests
• NuGet consumption, samples, documentation validation, and formatting checks