Python 3.15 Enters Feature Freeze with First Beta Release
The Python development team has released the first beta version of Python 3.15, marking the start of the feature freeze period ahead of its scheduled final release in October 2026. This update introduces several significant enhancements, including a stable application binary interface (ABI) for free-threaded CPython, which simplifies extension maintenance across minor versions. Key performance improvements feature a refined just-in-time (JIT) compiler, now delivering an 8-13 percent speed increase on Linux and macOS, and a new zero-overhead sampling profiler named Tachyon. Additionally, Python 3.15 adopts UTF-8 as the default text encoding and implements explicit lazy imports to accelerate application startup times. However, the incremental garbage collector introduced in Python 3.14 was reverted due to memory leak issues, with potential reintroduction deferred to version 3.16 pending further evaluation. This release continues the momentum of removing the global interpreter lock (GIL) to enable efficient multi-core concurrency, representing a major step forward in Python's evolution for high-performance computing environments.
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Python 3.15 Enters Feature Freeze with First Beta Release
The Python development team has released the first beta version of Python 3.15, marking the start of the feature freeze period ahead of its scheduled final release in October 2026. This update introduces several significant enhancements, including a stable application binary interface (ABI) for free-threaded CPython, which simplifies extension maintenance across minor versions. Key performance improvements feature a refined just-in-time (JIT) compiler, now delivering an 8-13 percent speed increase on Linux and macOS, and a new zero-overhead sampling profiler named Tachyon. Additionally, Python 3.15 adopts UTF-8 as the default text encoding and implements explicit lazy imports to accelerate application startup times. However, the incremental garbage collector introduced in Python 3.14 was reverted due to memory leak issues, with potential reintroduction deferred to version 3.16 pending further evaluation. This release continues the momentum of removing the global interpreter lock (GIL) to enable efficient multi-core concurrency, representing a major step forward in Python's evolution for high-performance computing environments.
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