Jannis Leidel
@jezdez.dev
🚲 Mobilitätswende jetzt!
🐍 PSF chair & fellow.
🎁 conda and friends at Anaconda.
📦 PyPA & 🎷Jazzband founder.
🕸️ mozilla data, ✍️MDN & 🎻 Django alum.
He/him
🐍 PSF chair & fellow.
🎁 conda and friends at Anaconda.
📦 PyPA & 🎷Jazzband founder.
🕸️ mozilla data, ✍️MDN & 🎻 Django alum.
He/him
Reposted by Jannis Leidel
Let's show up for The Carpentries!
The support the Python community has shown to PSF for its decision has given us hope in the sustainability of open science communities. Please consider extending your generosity to our organisation’s fundraising efforts, and help us to reach others aligned to our mission: carpentries.org/support/
Support The Carpentries
We are grateful to the individuals and organisations who provide financial support to The Carpentries. If you are interested in supporting our work, you can learn more about becoming a Member Organisa...
carpentries.org
November 7, 2025 at 5:03 PM
Let's show up for The Carpentries!
Reposted by Jannis Leidel
Conda in the Packaging Spectrum: From pip to Docker to Nix
If conda is a distribution, where does it fit alongside pip, Docker, and Nix? Part 2 of the 3-part series! 🚀
#conda #packaging #python
conda.org/blog/conda-p...
If conda is a distribution, where does it fit alongside pip, Docker, and Nix? Part 2 of the 3-part series! 🚀
#conda #packaging #python
conda.org/blog/conda-p...
Conda in the Packaging Spectrum: From pip to Docker to Nix | conda.org
Part 2 of the 'Conda Is Not PyPI' series, placing conda among pip, Docker, and Nix and explaining its middle-path design.
conda.org
November 4, 2025 at 2:38 PM
Conda in the Packaging Spectrum: From pip to Docker to Nix
If conda is a distribution, where does it fit alongside pip, Docker, and Nix? Part 2 of the 3-part series! 🚀
#conda #packaging #python
conda.org/blog/conda-p...
If conda is a distribution, where does it fit alongside pip, Docker, and Nix? Part 2 of the 3-part series! 🚀
#conda #packaging #python
conda.org/blog/conda-p...
Reposted by Jannis Leidel
As the PSF heads into our end-of-year fundraiser this month, we want to “connect the dots” and share a full picture of our current financial outlook: what’s happening, why, and how you can help sustain the future of Python and the PSF. 🧵
Connecting the Dots: Understanding the PSF’s Current Financial Outlook
As the PSF heads into our end-of-year fundraiser, we want to share information to help “connect the dots” and show a more complete picture of the PSF’s current financial outlook. You’ve heard from us on subjects related to our financial position from several different angles recently (a list of those posts is below). We’ve prioritized proactive communications, because we believe in transparency, we have trust in our community, and we value keeping you informed— we know how invested in and impacted by our work you are. We now want to pull those threads together in order to create some shared clarity on the big picture, and, hopefully, inspire you to action to support our fundraising efforts.
pyfound.blogspot.com
November 4, 2025 at 12:12 PM
As the PSF heads into our end-of-year fundraiser this month, we want to “connect the dots” and share a full picture of our current financial outlook: what’s happening, why, and how you can help sustain the future of Python and the PSF. 🧵
Reposted by Jannis Leidel
Do you know why Conda is not PyPI? Read my thoughts and those of my colleague @jezdez.dev here.
Conda ≠ PyPI
Conda isn’t just another Python package manager-it’s a multi-language, user-space distribution system.
In this 3-part series, we explore the fundamental differences between conda and PyPI.
Part 1 is live now 👇
conda.org/blog/conda-i...
#conda #packaging #python
Conda isn’t just another Python package manager-it’s a multi-language, user-space distribution system.
In this 3-part series, we explore the fundamental differences between conda and PyPI.
Part 1 is live now 👇
conda.org/blog/conda-i...
#conda #packaging #python
Conda ≠ PyPI: Why Conda Is More Than a Package Manager | conda.org
Part 1 of the 'Conda Is Not PyPI' series—why conda is a multi-language user-space distribution, not just a Python package manager.
conda.org
October 29, 2025 at 2:15 PM
Do you know why Conda is not PyPI? Read my thoughts and those of my colleague @jezdez.dev here.
Reposted by Jannis Leidel
⚞NEW⚟ “Trailblazing Python Security” dedicated talk track coming for #PyConUS 🛡️ 🐍🔥 We are looking for sponsors interested in supporting security in the Python ecosystem:
pycon.blogspot.com/2025/10/pyco...
bsky.app/profile/pyco...
#python #opensource #oss #security #supplychain
pycon.blogspot.com/2025/10/pyco...
bsky.app/profile/pyco...
#python #opensource #oss #security #supplychain
October 31, 2025 at 6:35 PM
⚞NEW⚟ “Trailblazing Python Security” dedicated talk track coming for #PyConUS 🛡️ 🐍🔥 We are looking for sponsors interested in supporting security in the Python ecosystem:
pycon.blogspot.com/2025/10/pyco...
bsky.app/profile/pyco...
#python #opensource #oss #security #supplychain
pycon.blogspot.com/2025/10/pyco...
bsky.app/profile/pyco...
#python #opensource #oss #security #supplychain
Reposted by Jannis Leidel
PyCon returns the to the US west coast in May
I'd love to see some talks about how Python is used in the entertainment industry - if you know someone who works with Python in that space please encourage them to submit a talk!
I'd love to see some talks about how Python is used in the entertainment industry - if you know someone who works with Python in that space please encourage them to submit a talk!
The wait is over — #PyConUS 2026 is here! 🙌
The #PyConUS 2026 site is now LIVE and the Call for Proposals is OPEN! We can't wait to welcome you to Long Beach, CA this spring and spotlight the incredible work happening across the Python community 🐍
👉 Details: pycon.blogspot.com/2025/10/pyco...
The #PyConUS 2026 site is now LIVE and the Call for Proposals is OPEN! We can't wait to welcome you to Long Beach, CA this spring and spotlight the incredible work happening across the Python community 🐍
👉 Details: pycon.blogspot.com/2025/10/pyco...
October 31, 2025 at 6:55 PM
PyCon returns the to the US west coast in May
I'd love to see some talks about how Python is used in the entertainment industry - if you know someone who works with Python in that space please encourage them to submit a talk!
I'd love to see some talks about how Python is used in the entertainment industry - if you know someone who works with Python in that space please encourage them to submit a talk!
Reposted by Jannis Leidel
The wait is over — #PyConUS 2026 is here! 🙌
The #PyConUS 2026 site is now LIVE and the Call for Proposals is OPEN! We can't wait to welcome you to Long Beach, CA this spring and spotlight the incredible work happening across the Python community 🐍
👉 Details: pycon.blogspot.com/2025/10/pyco...
The #PyConUS 2026 site is now LIVE and the Call for Proposals is OPEN! We can't wait to welcome you to Long Beach, CA this spring and spotlight the incredible work happening across the Python community 🐍
👉 Details: pycon.blogspot.com/2025/10/pyco...
October 31, 2025 at 6:09 PM
The wait is over — #PyConUS 2026 is here! 🙌
The #PyConUS 2026 site is now LIVE and the Call for Proposals is OPEN! We can't wait to welcome you to Long Beach, CA this spring and spotlight the incredible work happening across the Python community 🐍
👉 Details: pycon.blogspot.com/2025/10/pyco...
The #PyConUS 2026 site is now LIVE and the Call for Proposals is OPEN! We can't wait to welcome you to Long Beach, CA this spring and spotlight the incredible work happening across the Python community 🐍
👉 Details: pycon.blogspot.com/2025/10/pyco...
Reposted by Jannis Leidel
Thanks to our partners Arm, @github.com, and @awscloud.bsky.social, the PSF migrated #Python’s infrastructure to Arm-based systems; achieving zero downtime, lower costs, and a greener footprint. Results like this show the impact of corporate collaboration with #Python 💝🐍 www.arm.com/company/succ...
Python Software Foundation: Scaled with AWS Graviton, GitHub and Arm
Discover how the Python Software Foundation scaled sustainably with AWS Graviton and GitHub ARM64 runners, cutting costs and boosting developer productivity.
www.arm.com
October 31, 2025 at 3:22 PM
Thanks to our partners Arm, @github.com, and @awscloud.bsky.social, the PSF migrated #Python’s infrastructure to Arm-based systems; achieving zero downtime, lower costs, and a greener footprint. Results like this show the impact of corporate collaboration with #Python 💝🐍 www.arm.com/company/succ...
Reposted by Jannis Leidel
Hearts at the PSF are full today from the responses about the recent grant turn down news we shared. All of your kind words of support & solidarity, as well as your donations & new memberships, mean the world to us. We're so grateful to be in community with each of you 💛🐍💙
TLDR; The PSF has made the decision to put our community and our shared diversity, equity, and inclusion values ahead of seeking $1.5M in new revenue. Please read and share. pyfound.blogspot.com/2025/10/NSF-...
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🧵
The official home of the Python Programming Language
www.python.org
October 28, 2025 at 7:04 PM
Hearts at the PSF are full today from the responses about the recent grant turn down news we shared. All of your kind words of support & solidarity, as well as your donations & new memberships, mean the world to us. We're so grateful to be in community with each of you 💛🐍💙
Reposted by Jannis Leidel
In the past day we raised $65K+ USD and are thrilled to welcome 137 new Supporting Members! We truly hope you continue to follow us and share this story and more as we kick off our annual fundraiser in November. Thinking about becoming a PSF member? Info: www.python.org/psf/membersh...
October 28, 2025 at 7:05 PM
In the past day we raised $65K+ USD and are thrilled to welcome 137 new Supporting Members! We truly hope you continue to follow us and share this story and more as we kick off our annual fundraiser in November. Thinking about becoming a PSF member? Info: www.python.org/psf/membersh...
Reposted by Jannis Leidel
The latest PSF Board is excited to continue monthly Office Hours into 2026! We welcome you to join these sessions to share with us how we can help your local and project based communities, express your perspectives, and provide feedback for the PSF 🐍📣
A new PSF Board- Another year of PSF Board Office Hour sessions!
Greetings, Pythonistas- thank you so much for supporting the work of the PSF and the Python community! The newest PSF Board has decided to continue investing in connecting with the global Python community by running the PSF Board Office Hour sessions on the PSF Discord into 2026. We began running these sessions in September 2024, and they have proven to be a great method for the community to connect with the board and vice versa. The sessions have provided the PSF Board and Staff the opportunity to hear what our community is up to and what challenges they are facing, as well as receive invaluable feedback about how the PSF can continue to improve our service to the Python community.
pyfound.blogspot.com
October 28, 2025 at 4:35 PM
The latest PSF Board is excited to continue monthly Office Hours into 2026! We welcome you to join these sessions to share with us how we can help your local and project based communities, express your perspectives, and provide feedback for the PSF 🐍📣
Reposted by Jannis Leidel
This was a tough but necessary decision - I posted my own notes on this here, from the perspective of a current PSF board member https://simonwillison.net/2025/Oct/27/psf-withdrawn-proposal/
https://fosstodon.org/@ThePSF/115446659188615376
https://fosstodon.org/@ThePSF/115446659188615376
The PSF has withdrawn a $1.5 million proposal to US government grant program
The Python Software Foundation was recently "recommended for funding" (NSF terminology) for a $1.5m grant from the US government National Science Foundation to help improve the security of the Python …
simonwillison.net
October 27, 2025 at 8:36 PM
This was a tough but necessary decision - I posted my own notes on this here, from the perspective of a current PSF board member https://simonwillison.net/2025/Oct/27/psf-withdrawn-proposal/
https://fosstodon.org/@ThePSF/115446659188615376
https://fosstodon.org/@ThePSF/115446659188615376
Reposted by Jannis Leidel
This is what I’m talking about!
Python is for everyone! Always!
Y’all, if you aren’t a PSF member, consider joining! 🖤
Python is for everyone! Always!
Y’all, if you aren’t a PSF member, consider joining! 🖤
TLDR; The PSF has made the decision to put our community and our shared diversity, equity, and inclusion values ahead of seeking $1.5M in new revenue. Please read and share. pyfound.blogspot.com/2025/10/NSF-...
🧵
🧵
The official home of the Python Programming Language
www.python.org
October 27, 2025 at 3:44 PM
This is what I’m talking about!
Python is for everyone! Always!
Y’all, if you aren’t a PSF member, consider joining! 🖤
Python is for everyone! Always!
Y’all, if you aren’t a PSF member, consider joining! 🖤
Reposted by Jannis Leidel
It was the right thing to do.
It wouldn’t be worthwhile if we couldn’t stand behind the diverse communities that form the backbone of Python.
It’s tough cos the ecosystem is expanding faster than resources. Sustaining takes real funding and responsibilities.
Our year-end fundraising is coming soon.
It wouldn’t be worthwhile if we couldn’t stand behind the diverse communities that form the backbone of Python.
It’s tough cos the ecosystem is expanding faster than resources. Sustaining takes real funding and responsibilities.
Our year-end fundraising is coming soon.
TLDR; The PSF has made the decision to put our community and our shared diversity, equity, and inclusion values ahead of seeking $1.5M in new revenue. Please read and share. pyfound.blogspot.com/2025/10/NSF-...
🧵
🧵
The official home of the Python Programming Language
www.python.org
October 27, 2025 at 3:57 PM
It was the right thing to do.
It wouldn’t be worthwhile if we couldn’t stand behind the diverse communities that form the backbone of Python.
It’s tough cos the ecosystem is expanding faster than resources. Sustaining takes real funding and responsibilities.
Our year-end fundraising is coming soon.
It wouldn’t be worthwhile if we couldn’t stand behind the diverse communities that form the backbone of Python.
It’s tough cos the ecosystem is expanding faster than resources. Sustaining takes real funding and responsibilities.
Our year-end fundraising is coming soon.
Reposted by Jannis Leidel
I'd also like to shout out @carpentries.carpentries.org for leading the way on this, having made a similar decision earlier this year.
October 27, 2025 at 3:47 PM
I'd also like to shout out @carpentries.carpentries.org for leading the way on this, having made a similar decision earlier this year.
Reposted by Jannis Leidel
If you find yourself moved and asking, how can I be part of this organization?! One answer is joining as a Supporting Member: psfmember.org/civicrm/cont...
Python Software Foundation Supporting Member – Python Software Foundation
psfmember.org
October 27, 2025 at 4:56 PM
If you find yourself moved and asking, how can I be part of this organization?! One answer is joining as a Supporting Member: psfmember.org/civicrm/cont...
Reposted by Jannis Leidel
The Python Software Foundation shows more spine than every single tech giant in just one single decision.
> Diversity, equity, and inclusion are core to the PSF’s values
https://pyfound.blogspot.com/2025/10/NSF-funding-statement.html
> Diversity, equity, and inclusion are core to the PSF’s values
https://pyfound.blogspot.com/2025/10/NSF-funding-statement.html
The PSF has withdrawn $1.5 million proposal to US government grant program
In January 2025, the PSF submitted a proposal to the US government National Science Foundation under the Safety, Security, and Privacy of Open Source Ecosystems program to address structural vulnerabilities in Python and PyPI. It was the PSF’s first time applying for government funding, and navigating the intensive process was a steep learning curve for our small team to climb. Seth Larson, PSF Security Developer in Residence, serving as Principal Investigator (PI) with Loren Crary, PSF Deputy Executive Director, as co-PI, led the multi-round proposal writing process as well as the months-long vetting process. We invested our time and effort because we felt the PSF’s work is a strong fit for the program and that the benefit to the community if our proposal were accepted was considerable.
We were honored when, after many months of work, our proposal was recommended for funding, particularly as only 36% of new NSF grant applicants are successful on their first attempt. We became concerned, however, when we were presented with the terms and conditions we would be required to agree to if we accepted the grant. These terms included affirming the statement that we “do not, and will not during the term of this financial assistance award, operate any programs that advance or promote DEI, or discriminatory equity ideology in violation of Federal anti-discrimination laws.” This restriction would apply not only to the security work directly funded by the grant, **but to any and all activity of the PSF as a whole**. Further, violation of this term gave the NSF the right to “claw back” previously approved and transferred funds. This would create a situation where money we’d already spent could be taken back, which would be an enormous, open-ended financial risk.
Diversity, equity, and inclusion are core to the PSF’s values, as committed to in our mission statement:
> _The mission of the Python Software Foundation is to promote, protect, and advance the Python programming language, and to support and facilitate the growth of**a diverse and international community** of Python programmers._
Given the value of the grant to the community and the PSF, we did our utmost to get clarity on the terms and to find a way to move forward in concert with our values. We consulted our NSF contacts and reviewed decisions made by other organizations in similar circumstances, particularly The Carpentries.
In the end, however, the PSF simply can’t agree to a statement that we won’t operate any programs that “advance or promote” diversity, equity, and inclusion, as it would be a betrayal of our mission and our community.
We’re disappointed to have been put in the position where we had to make this decision, because we believe our proposed project would offer invaluable advances to the Python and greater open source community, protecting millions of PyPI users from attempted supply-chain attacks. The proposed project would create new tools for automated proactive review of all packages uploaded to PyPI, rather than the current process of reactive-only review. These novel tools would rely on capability analysis, designed based on a dataset of known malware. Beyond just protecting PyPI users, the outputs of this work could be transferable for all open source software package registries, such as NPM and Crates.io, improving security across multiple open source ecosystems.
In addition to the security benefits, the grant funds would have made a big difference to the PSF’s budget. The PSF is a relatively small organization, operating with an annual budget of around $5 million per year, with a staff of just 14. $1.5 million over two years would have been quite a lot of money for us, and easily the largest grant we’d ever received. Ultimately, however, the value of the work and the size of the grant were not more important than practicing our values and retaining the freedom to support every part of our community. The PSF Board voted unanimously to withdraw our application.
Giving up the NSF grant opportunity—along with inflation, lower sponsorship, economic pressure in the tech sector, and global/local uncertainty and conflict—means the PSF needs financial support now more than ever. We are incredibly grateful for any help you can offer. If you're already a PSF member or regular donor, you have our deep appreciation, and we urge you to share your story about why you support the PSF. Your stories make all the difference in spreading awareness about the mission and work of the PSF.
How to support the PSF:
* Become a Member: When you sign up as a Supporting Member of the PSF, you become a part of the PSF. You’re eligible to vote in PSF elections, using your voice to guide our future direction, and you help us sustain what we do with your annual support.
* Donate: Your donation makes it possible to continue our work supporting Python and its community, year after year.
* Sponsor: If your company uses Python and isn’t yet a sponsor, send them our sponsorship page or reach out to [email protected] today. The PSF is ever grateful for our sponsors, past and current, and we do everything we can to make their sponsorships beneficial and rewarding.
pyfound.blogspot.com
October 27, 2025 at 4:04 PM
The Python Software Foundation shows more spine than every single tech giant in just one single decision.
> Diversity, equity, and inclusion are core to the PSF’s values
https://pyfound.blogspot.com/2025/10/NSF-funding-statement.html
> Diversity, equity, and inclusion are core to the PSF’s values
https://pyfound.blogspot.com/2025/10/NSF-funding-statement.html
Reposted by Jannis Leidel
TLDR; The PSF has made the decision to put our community and our shared diversity, equity, and inclusion values ahead of seeking $1.5M in new revenue. Please read and share. pyfound.blogspot.com/2025/10/NSF-...
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🧵
The official home of the Python Programming Language
www.python.org
October 27, 2025 at 2:47 PM
TLDR; The PSF has made the decision to put our community and our shared diversity, equity, and inclusion values ahead of seeking $1.5M in new revenue. Please read and share. pyfound.blogspot.com/2025/10/NSF-...
🧵
🧵
Reposted by Jannis Leidel
Please congratulate our newest PSF Fellow Members for Q3, 2025! Their continued contributions to the Python ecosystem are so very important to our community. #python
Announcing Python Software Foundation Fellow Members for Q3 2025! 🎉
The PSF is pleased to announce its third batch of PSF Fellows for 2025! Let us welcome the new PSF Fellows for Q3! The following people continue to do amazing things for the Python community:
pyfound.blogspot.com
October 22, 2025 at 3:41 PM
Please congratulate our newest PSF Fellow Members for Q3, 2025! Their continued contributions to the Python ecosystem are so very important to our community. #python
Reposted by Jannis Leidel
Check out this post by @diegor.it about the latest CPython sprint! We send a special thanks to Arm for hosting the event and investing in the future of #Python 💛🐍💙 pyfound.blogspot.com/2025/10/cpyt...
CPython Core Dev Sprint 2025 at Arm Cambridge: The biggest one yet
pyfound.blogspot.com
October 20, 2025 at 4:46 PM
Check out this post by @diegor.it about the latest CPython sprint! We send a special thanks to Arm for hosting the event and investing in the future of #Python 💛🐍💙 pyfound.blogspot.com/2025/10/cpyt...
Reposted by Jannis Leidel
🎯 The Python community has achieved a major milestone with asyncio now scaling across multiple cores in Python 3.14. Kumar Aditya shares the journey of reimagining asyncio's internals for a thread-safe, lock-free architecture.
Dive into the technical details: buff.ly/c5CFYt0
Dive into the technical details: buff.ly/c5CFYt0
October 6, 2025 at 5:00 PM
🎯 The Python community has achieved a major milestone with asyncio now scaling across multiple cores in Python 3.14. Kumar Aditya shares the journey of reimagining asyncio's internals for a thread-safe, lock-free architecture.
Dive into the technical details: buff.ly/c5CFYt0
Dive into the technical details: buff.ly/c5CFYt0
Reposted by Jannis Leidel
Trotz des immensen möglichen Schadens der #Chatkontrolle für Meinungsfreiheit, Pressefreiheit, Privatsphäre, Demokratie und IT-Sicherheit ist das Thema medial derzeit noch ganz schön unterberichtet. Hier steht, um was es eigentlich geht: netzpolitik.org/2025/fragen-...
Fragen und Antworten: Warum ist Chatkontrolle so gefährlich für uns alle?
Die Chatkontrolle gilt weithin als Ende der verschlüsselten und privaten Kommunikation, also als Gefahr für die Demokratie und technisches Sicherheitsrisiko für die digitale Welt. Wir erklären und kom...
netzpolitik.org
October 6, 2025 at 5:45 AM
Trotz des immensen möglichen Schadens der #Chatkontrolle für Meinungsfreiheit, Pressefreiheit, Privatsphäre, Demokratie und IT-Sicherheit ist das Thema medial derzeit noch ganz schön unterberichtet. Hier steht, um was es eigentlich geht: netzpolitik.org/2025/fragen-...
Reposted by Jannis Leidel
The PSF joined the @openssf.org & others in signing “Open Infrastructure is Not Free.” Funding gaps in the open source industry mean critical infrastructure lacks support. Corporations benefiting from it must invest to sustain it.
Read more ➡️
Read more ➡️
September 23, 2025 at 2:57 PM
The PSF joined the @openssf.org & others in signing “Open Infrastructure is Not Free.” Funding gaps in the open source industry mean critical infrastructure lacks support. Corporations benefiting from it must invest to sustain it.
Read more ➡️
Read more ➡️
Reposted by Jannis Leidel
We're excited to announce the results of the 2025 election for the PSF Board! Sending a big thank you to the nominees, our outgoing Board members, and our community for participating this year- we are so grateful to be in community with all of you 💙💛
Announcing the 2025 PSF Board Election Results!
The 2025 election for the PSF Board created an opportunity for conversations about the PSF's work to serve the global Python community. We appreciate community members' perspectives, passion, and engagement in the election process this year.
pyfound.blogspot.com
September 16, 2025 at 5:16 PM
We're excited to announce the results of the 2025 election for the PSF Board! Sending a big thank you to the nominees, our outgoing Board members, and our community for participating this year- we are so grateful to be in community with all of you 💙💛
Reposted by Jannis Leidel
Attacks against F/OSS projects & leveraging package management infrastructure are on the rise.
If you maintain any F/OSS project, maybe go enable 2FA now & be cautious when clicking links.
If you maintain any F/OSS project, maybe go enable 2FA now & be cautious when clicking links.
FYI, I got an obvious phishing attempt in my inbox from `[email protected]` that was masquerading as a security breach notification. It made it past gmail's spam filters.
The link goes to the `github.rustfoundation.dev` domain.
The link goes to the `github.rustfoundation.dev` domain.
September 12, 2025 at 3:59 PM
Attacks against F/OSS projects & leveraging package management infrastructure are on the rise.
If you maintain any F/OSS project, maybe go enable 2FA now & be cautious when clicking links.
If you maintain any F/OSS project, maybe go enable 2FA now & be cautious when clicking links.