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danzin

@danzin@mastodon.social

mastodon 4.8.0-nightly.2026-10-06

Brazilian (experienced) hobbyist Pythonista. Pythonista amador (experiente).
#python
He/him/ele

0 Followers

0 Following

30 Posts

Joined July 25, 2023

GitHub:

https://github.com/devdanzin

discuss.python.org:

https://discuss.python.org/u/devdanzin/summary

danzin @danzin@mastodon.social

· 6mo ago

Replying to

In related news, I've reported a couple hundred bugs on Python C extensions this week, that became a couple dozen issues and PRs. Very happy with the results, but the most important part to me is building (and releasing) the tools and running the analyses. Shout out to the maintainers of h5py, lxml, Cython, APSW, psutil, kiwisolver, pyhacl, cereggii, atom, enaml, and maybe others I'm forgetting, for being receptive and giving feedback and guidance. #Python

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danzin @danzin@mastodon.social

· 6mo ago

Replying to

The results so far? Fixes merged in 14 projects! Massive shoutout to the maintainers of simplejson, Cython, memray, h5py, greenlet, bottleneck, guppy3, bitarray, igraph, APSW, Pillow, regex, and many others! The feedback they gave me, especially when pointing out my tool's false positives, was invaluable for making the scanners better. It's been incredibly rewarding to see the tools find interesting bugs and watch the community merge the fixes so quickly. #Python #CPython

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danzin @danzin@mastodon.social

· 8mo ago

RE: https://mastodon.social/@avesbrasil/115991951271797869 If you're into tropical birds, I recommend giving @avesbrasil@mastodon.social a look and hopefully a follow. It will show you amazing photos, songs/sounds and distribution maps of many interesting species in Brazil. It's currently criminally underfollowed at only 508 followers. #birds #birdwatching #birding #birdphotography #BrazilianBirds #birdsongs #avesbrasil

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danzin @danzin@mastodon.social

· 9mo ago

There's another researcher, Zhengyu Liu, who's been finding CPython crashes (mostly use-after-free) at breakneck speed (19 in 5 days!): https://github.com/python/cpython/issues?q=is%3Aissue%20author%3Ajackfromeast

Not sure about what technique they're using, but their site states they they favor "leveraging program analysis approaches to detect/exploit/patch vulnerabilities in real-world complex applications and systems".

Their reports are comprehensive, with great presentation and details.

https://jackfromeast.github.io/

#CPython #Python #Crash

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danzin @danzin@mastodon.social

· 5mo ago

Comprei passagens e reservei hotel para a Python Brasil 2026 @pythonbrasil@pynews.com.br.

Tudo, desde o ingresso até as passagens, cancelável, pois ninguém sabe o dia de amanhã.

Vontade enorme de dar uma palestra, mas não sei se o meu psicológico aguenta. Acho que conseguiria fazer, mas o estresse e a ressaca depois não sei se vale a pena. Talvez uma lightning talk seja mais tranquilo de fazer.

Espero que o @villares@ciberlandia.pt consiga ir.

#PythonBrasil2026 #PythonBrasil #pybr2026 #Python

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danzin @danzin@mastodon.social

· 2mo ago

Se você tem um glicosímetro G-Tech Lite Smart e fica indignade com a porcaria de App dele, tenho um script Python que baixa as medições e uma página HTML que mostra gráficos e várias informações a partir delas.

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danzin @danzin@mastodon.social

· 5mo ago

Joana Francesa, música que o Chico escreveu com palavras em francês e significados em português, ou o contrário.

Sempre adorei essa música, surpreso que ninguém tenha citado ainda.

https://www.youtube.com/watch?v=jjj50Qz9x_Y

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danzin @danzin@mastodon.social

· 3mo ago

Replying to

@hongminhee@hollo.social 🫂

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danzin @danzin@mastodon.social

· 6mo ago

Replying to

Historically, automated bug-finding tools have a bad habit of producing high-noise findings (and now worse: convincing AI slop) that just wastes maintainer time.

I built cext-review-toolkit using multiple specialized agents to find bugs, and I try to reproduce every finding from pure Python before reporting it.

Human review + pure-Python reproducers act as a necessary filter against false positives.

#Python #CPython

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danzin @danzin@mastodon.social

· 5mo ago

Replying to

@mgorny@social.treehouse.systems While not a Gentoo user, I deeply appreciate the work you do spotting, reporting and fixing issues in upstream projects. For many of these projects I follow (mostly in the Python ecosystem), contributions by Gentoo people are an important way of keeping things compatible, crash-free, etc. Thank you for that!

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danzin @danzin@mastodon.social

· 6mo ago

I've created a CPython umbrella issue for C bugs found with a new tool: https://github.com/python/cpython/issues/146102

The umbrella issue reported 47 bugs, 18 have been filed by various people, and 14 have been fixed. Each bug has an explanation about it linked in the issue.

That means you can join the fun: pick a bug, create an issue, and fix it in a PR!

There's also a different umbrella issue with more than a hundred (less detailed) bugs to pick from: https://github.com/python/cpython/issues/146103

Have fun!

#Python #CPython

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danzin @danzin@mastodon.social

· 9mo ago

@stefano @openmeteo @grunfink @FediFollows Thank you so much, I love it! There's a tiny translation mistake: in pt-br it says "granizo", meaning "hail", where I believe it should say "chuvisco", meaning "drizzle". I tried to figure out whether it comes from the API you use or your code, but wasn't able to. If you can point me to the right place to report this, I'd be glad to! Thanks again!

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danzin @danzin@mastodon.social

· 6mo ago

@paulox@fosstodon.org This might interest you (seems related to your upcoming talk): @danzin@mastodon.social

mastodon.social

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danzin @danzin@mastodon.social

· 6mo ago

Replying to

I also built ft-review-toolkit (using ThreadSanitizer) to check for free-threading readiness, which has found real data races in 12 extensions so far.

If you maintain a Python C extension and want a high-quality, human-reviewed bug report (or help migrating to free-threading), just let me know!

All the toolkits are open source: https://github.com/devdanzin/cext-review-toolkit https://github.com/devdanzin/ft-review-toolkit

#Python #CPython

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danzin @danzin@mastodon.social

· 5mo ago

Replying to

@calotaspolares@masto.donte.com.br Fechou 10 anos de faculdade, 1 deles só faltava essa matéria (que fiz umas 4 vezes) pra terminar. A prova era completamente visual, li dois livros sobre o tema e não adiantava, só tinha que olhar pra peças de anatomia e saber o nome de onde tinha um alfinete. Tinha que decorar, eu não tenho memória visual. Tinha tempo (acho que eram 15 minutos). E era no esquema "saiu o primeiro aluno, ninguém mais entra". Minha neurodivergência não conhecida não me ajudava. Nada de adaptação.

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danzin @danzin@mastodon.social

· 8mo ago

Replying to

@ThePSF @pypi Thanks Anthropic and everyone that worked hard to make this happen. I hope this is just the beginning and a lot more contributions to the PSF will happen. The Python ecosystem will become better and better this way. #Python #PSF #Anthropic

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danzin @danzin@mastodon.social

· 6mo ago

Replying to

@adamchainz Here you go: https://gist.github.com/devdanzin/ddbcdf1bb41194e2f81a0feab6c15616 https://gist.github.com/devdanzin/4cd3234a5ede15c7688b590d95b0dfe9 https://gist.github.com/devdanzin/7f1e9d05849cea565b39e5eaaee207b5 I hope these help. Any feedback is welcome. Please let me know if you'd like me to open umbrella issues for the reports and/or individual issues for the findings, as well as PRs. Thanks again!

gist.github.com

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danzin @danzin@mastodon.social

· 7mo ago

Replying to

@miguelgrinberg Not sure I agree that has to be said, but I agree that it should be stated that LLMs are allowed to all kinds of contributors, as long a human signs the CLA and takes full responsibility for the contributions.

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danzin @danzin@mastodon.social

· 7mo ago

Replying to

@miguelgrinberg I see your point, makes sense. I agree disclosure would help. One data point you might want to take a look at for your article is searching for "LLM" and specific tool names in issues and PRs. It's mostly core developers asking people not to use these tools as they're using them. But there are a couple of cases of contributors disclosing that analysis or coding was made or helped by such a tool.

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danzin @danzin@mastodon.social

· 8mo ago

Replying to

@lorenipsum 🫂

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danzin @danzin@mastodon.social

· 7mo ago

Replying to

labeille Package Registry stats

Top 3.15 Blockers (364 packages):

PyO3 / Rust / maturin: 111
C extension build failures: 108
pydantic-core (transitive PyO3): 69
numpy / scipy / meson: 43

Once PyO3 adds 3.15 support, ~180 more packages will unlock (PyO3 direct + pydantic-core transitive)

Skip Reasons (418 packages):

Monorepo subpackage (Azure, GCloud, etc.): 214
No test suite found: 70
No source repository: 52
Type stub packages: 42

#Python #CPython #JIT #registry #labeille

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danzin @danzin@mastodon.social

· 7mo ago

Replying to

@miguelgrinberg @hugovk So raising contributor productivity would be one, maybe the biggest, reason people use LLMs on CPython, especially for code changes that span a lot of tedious, mechanical work. Submitting higher quality code is another: LLMs can do a (internal) pre-review of the PR, can tell you about details in the docs or the code you forgot about, can write comprehensive tests faster, etc. About crediting, I think it's a transparent way to say "(some) of this was written by a tool".

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danzin @danzin@mastodon.social

· 7mo ago

Replying to

@miguelgrinberg I've had to e.g. ask Claude Code to credit Gemini as the LLM tool I used, so transparency is feasible and IMO helps. People who want nothing to do with LLM generated code, reviewers, all get a clear signal. The DevGuide policy doesn't mention disclosure of or crediting LLM tools. I expect more contributions have been with them. If your position is that it should always be disclosed, I can agree to that to a point. Say, when a significant part of the code was generated by an LLM.

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danzin @danzin@mastodon.social

· 6mo ago

Replying to

@drlazor8 Thank you for your kind words, working with you has been a real pleasure! The tool has been evolving since I created the pyhacl report, I'll soon do a follow up review to see if the new features catch anything else interesting. And please let me know if you have other C extensions you'd like reviewed :)

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danzin @danzin@mastodon.social

· 5mo ago

@geraldew@fosstodon.org Hi, is geraldew@mastodon.social you, or is someone impersonating you?

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