Maintain Python upstream (https://xitter.cf/t.co/ezHbPsRtb5) and downstream (RHEL and Fedora) for Red Hat. Python core developer.

France - he/him
Joined July 2015
Victor Stinner 🐍 retweeted
My 1st big ship at CPython Core Sprint at OpenAI uuid7() will be 30x faster in Python 3.16 Imagine how much more FastAPI code you can ship now 🧠 cc @tiangolo
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Victor Stinner 🐍 retweeted
The PSF is hiring a CPython Developer in Residence! Full-time, remote, $70K–170K (US) or comparable contractor rates abroad. Help keep Python’s core healthy and support the volunteers who maintain it. Apply by Nov 19: pythonsoftwarefoundation.app… #Python pythonsoftwarefoundation.app…
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Victor Stinner 🐍 retweeted
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My recent work on PyBytesWriter and PyUnicodeWriter C API, bugfixes, optimizations, and documentation changes: vstinner.github.io/optimize-… PyBytesWriter is now 1.28x faster than Python 3.15 and PyUnicodeWriter can avoid memory copies. Detect buffer overflow in debug mode.
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Victor Stinner 🐍 retweeted
Python 3.15 is OUT 🐍🚀 Lazy imports, Tachyon in the stdlib, frame pointers on by default, frozendict, better error messages... this one is LOADED 🔥🔥🔥 Go upgrade 🤘 discuss.python.org/t/python-…
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Victor Stinner 🐍 retweeted
2012: @gvanrossum rejects @VictorStinner's frozendict pep, citing @raymondh: "use of frozendict is low" 2026: frozendict ships as a builtin in python 3.15. same author the man was immutable
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Victor Stinner 🐍 retweeted
In July 2026 Python core developers and special guests sat down at the #Python Language Summit at #EuroPython 2026, to discuss the future of the Python programming language including free-threading, #Rust, garbage collection, and namespaces. Find a summary on the PSF blog ⬇️ pyfound.blogspot.com/2026/09…
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I just optimized PyFloat_PackN() C functions in Python using __builtin_bswapN() to swap bytes. Problem: GCC does crash and clang miscompiles the 16-bit function which uses _Float16 on IBM s390x! GCC bug report: bugzilla.redhat.com/show_bug… clang bug report: github.com/llvm/llvm-project…
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Victor Stinner 🐍 retweeted
The inaugural Python Packaging Council membership has been announced as a result of voting of PSF members. Congrats @pradyunsg @dstufft @HenrySchreiner3 @ralfgommers, and thank you for your service to the Python community!
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Victor Stinner 🐍 retweeted
This is what happens when a CPU has forty-eight years of never removing anything
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Victor Stinner 🐍 retweeted
John Tukey the Fast Fourier Transform (FFT) inventor, who coined both "bit" and "software" died exactly 26 years ago today. The Fast Fourier Transform (FFT), one of the most important algorithms in signal processing and data analysis, was introduced by Tukey & Cooley in 1965. In 1805, Gauss - studying the orbits of asteroids Pallas and Juno - came up with a method to interpolate their trajectories from discrete samples. What he came up with was mathematically very close to the modern FFT but Gauss never published that work, and didn’t analyze its computational complexity. It predated even Fourier’s 1822 work on heat diffusion - but without the framing or generalization that Cooley & Tukey would bring 160 years later. In 1965, Cooley & Tukey published their now-famous algorithm that reduced the cost of computing a Discrete Fourier Transform from 𝑂(𝑛²) to 𝑂(𝑛 log⁡𝑛). This leap made real-time signal processing and digital media compression feasible. From radio telescopes to JPEGs, from audio codecs to quantum mechanics - the FFT is everywhere. It’s one of the most important (and elegant) algorithms of the 20th century - rooted in the genius of Gauss, but brought to life in the computer age.
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Victor Stinner 🐍 retweeted
Great summary from legendary @fabynou about how us programmers might feel and approach to the current LLM revolution. Worth reading for any skeptical programmer... We (and others) been there before. We just need to evolve 🦖 fabiensanglard.net/extinct/i…
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Victor Stinner 🐍 retweeted
I’m very happy to share that Karrot is now sponsoring the @ThePSF ! I hope to see more tech companies from Asia join and support the Python community as well. :) python.org/psf/sponsors/
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New long article on PEP 814 Add frozendict built-in type vstinner.github.io/pep-814-a… Donghee Na @dongheena92 & me wrote PEP 814 to add frozendict implemented in C. Here is the long journey of adding the type to Python 3.15: implementation, stdlib changes, optimizations, complex bugs.
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I'm writing an article series on Free Threading internals. The 3rd article vstinner.github.io/free-thre… introduces PyMutex: one byte lock with fast, inlineable lock and unlock functions for the common uncontended case. The design is based on WebKit's WTF::Lock.
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Victor Stinner 🐍 retweeted
A French engineer who lives quietly in Paris has spent 30 years writing software that the entire internet now runs on without knowing his name. He wrote the code that streams every YouTube video, every Netflix show, every TikTok clip. He wrote the code that runs the virtual servers underneath AWS, Google Cloud, and Microsoft Azure. He calculated more digits of pi than anyone in history. He has no Twitter. He has no marketing. He just keeps shipping. His name is Fabrice Bellard. Here is the story, because almost nobody outside the systems programming world knows what one man has built. Fabrice was born in 1972 in Grenoble, France. He studied at École Polytechnique, the top French engineering school. He never went to Silicon Valley. He never built a startup empire. He just wrote code. In 2000 he started a project called FFmpeg, an open-source multimedia framework for encoding, decoding, and streaming video. He was 28. The project did one thing nobody else had done well. It handled every video and audio format that existed, in one library, on every operating system. He led it himself for years. Today FFmpeg is the invisible engine of the internet. YouTube uses it. Netflix uses it. VLC uses it. Chrome and Firefox use parts of it. Every Android phone, every iPhone, every smart TV, every video editing tool you have ever touched runs FFmpeg somewhere underneath. If you have watched a video on a screen in the last 20 years, Fabrice's code processed it. He was not done. In 2003 he started QEMU, a machine emulator and virtualizer. He wrote it solo until version 0.7.1 in 2005. QEMU lets you run any operating system on any other operating system. It became the foundation of modern virtualization. KVM, the Linux kernel hypervisor, runs on top of QEMU. Every major cloud provider, AWS, Google Cloud, Microsoft Azure, IBM Cloud, runs virtual machines on infrastructure built around it. The Quick Emulator is the most cited piece of cloud infrastructure code on Earth. He kept going. In 2001 he won the International Obfuscated C Code Contest with a small C compiler that grew into TCC, the Tiny C Compiler. TCC can compile and boot a Linux kernel from source in under 15 seconds. In 2004 he calculated the most digits of pi ever computed at the time, using a personal desktop computer and an algorithm he derived himself called Bellard's formula. In 2011 he wrote a complete PC emulator in pure JavaScript that runs Linux in your browser, a project called JSLinux that engineers still cannot believe is real. In 2019 he released QuickJS, a small but complete JavaScript engine that fits where V8 cannot. In 2021 he released NNCP, a neural network based lossless data compressor that immediately took the lead on the Large Text Compression Benchmark. Then he turned his attention to large language models. He built TextSynth Server, a web server with a REST API for running LLMs locally. He released ts_zip and ts_sms, compression utilities that use language models to compress text and short messages at ratios traditional algorithms cannot reach. He released TSAC, a very low bitrate audio compression system. In December 2025 he released Micro QuickJS, a new JavaScript engine for microcontrollers, separate from QuickJS, designed for environments with almost no memory. Fabrice co-founded a telecom company called Amarisoft in 2012, where he serves as CTO. Amarisoft builds 4G and 5G base station software used by carriers and labs around the world. He has been running it for over a decade while continuing to ship personal projects from his own home page at bellard dot org He has no Twitter. He has no Instagram. He gives almost no interviews. His personal website is a flat list of projects with no styling, no fonts, no marketing copy. Just titles and links. A quiet French engineer who never moved to Silicon Valley wrote the code that quietly runs the internet. He is still shipping.
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Victor Stinner 🐍 retweeted
The Steering Council has asked for a proper PEP for the CPython JIT. I’m happy to help coordinate that work. If you want to contribute as author, reviewer, or with any related input, please get in touch. discuss.python.org/t/an-anno…
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I'm writing an article serie on Free Threading internals. The second article vstinner.github.io/free-thre… analyzes immortal objects, deferred reference count, and stack references which reduce reference count contention by optimizing Py_INCREF()/Py_DECREF().
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