Py.Amsterdam Meetup at ABN AMRO

🎉 Py.Amsterdam Meetup at ABN AMRO

The Python community in Amsterdam is thriving, and we're thrilled to invite you to our next Py.Amsterdam meetup, this time hosted at ABN AMRO! Join us for an evening full of insightful talks, community bonding, and all things Python. 🐍
🗓 When: April 29th
📍 Where: Gustav Mahlerlaan 10, 1082 PP in Amsterdam (second door)
💬 What: Talks, lightning sessions, and networking with the best Pythonistas around.

🔹 Agenda

• 17:30 | 🏢 Doors Open
• 18:00 | 🎤 Eight Python Performance Mistakes I Won’t Make Again | Sasha Romijn
• 18:40 | 🍕 Networking with food & drinks
• 19:10 | 🎤 Zero to Shipped: The Git Log Doesn’t Lie | Jazzley Louisville and Jack Voorham
• 20:00 | 🎤 Lightning Talks: The 'maintained fork' of the popular Python package httpx | Michiel

📌 Important: Don’t forget to bring your ID —

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🎤 Eight Python Performance Mistakes I Won’t Make Again
A client was happy with a prototype I delivered, except for one detail: they needed my code to be about 100 times faster. I got there eventually, but through a lot of confusion and mistakes—which I’ll share with you, so you don’t have to go through them yourself.

Sasha Romijn - Mastodon | Bluesky - Sasha is an independent developer and community organiser with over a decade of Python experience. A former Django core developer and co-organiser of several Django conferences, they now work mostly on open source software related to internet infrastructure, network engineering, and internet standards. They’ve also been part of the Write the Docs conference team since 2018 and enjoy side projects like the Less Obvious Conference Checklist and Happiness Packets, which focus on improving the tech community in small but meaningful ways.

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🎤 Zero to Shipped: The Git Log Doesn’t Lie
What does your first real Python project actually teach you? In this talk, we’ll walk through what we learned while building a PySpark climate risk pipeline at ABN AMRO, starting from almost zero experience and ending with something running in production.

Using the project’s actual git history, we’ll show the mistakes, pivots, and lessons that shaped how we work now: Python packaging migrations from setup.cfg to Poetry to uv, import and environment issues, PySpark pitfalls, testing Spark code properly with pytest, and the kinds of debugging decisions that feel reasonable when you don’t yet know better. It’s a practical and honest look at learning Python engineering in the middle of a real project, with a focus on the things tutorials usually skip.

Jazzley Louisville and Jack Voorham work at ABN AMRO, where they build Python and PySpark-based data pipelines for climate risk assessment. This project was the first big production Python project for both of them, and most of the lessons in this talk were learned the hard way while building it together. They’re interested in practical engineering, developer tooling, and making complex systems easier to understand.

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🎤 Lightning talks

• The 'maintained fork' of the popular Python package httpx.
  httpxyz; forking a top-100 Python package
  httpx is one of Python’s most popular HTTP clients, used by the OpenAI and Anthropic SDKs among thousands of others. When the project stalled: no releases since late 2024, issues hidden, discussions closed, we forked it. This talk is about that decision: when a fork is justified, how we approach the fork, and what it takes to ship and maintain a high-profile open source package.
  Michiel Beijen (Mastodon) is a software engineer based in Leiden, works at Samotics, is organizer of Python Leiden, and co-maintainer of httpxyz.
  Michiel's blog post details the reasons for the fork:
  https://tildeweb.nl/~michiel/httpxyz.html

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💬 Want to give a talk? We're always looking for speakers! Whether you have a deep dive, a quick lightning talk, or something in between — we'd love to hear from you. Send us an email at info@py.amsterdam or fill out the speaker form on our website with the following details:

• Talk Title
• Talk Abstract
• and Speaker Bio.
• Don't be shy, all experience levels are welcome!

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👥 About our host: ABN AMRO

ABN AMRO is one of the Netherlands' largest and most established banks, with a history spanning over 300 years. Headquartered in Amsterdam, the bank serves millions of retail, private, and corporate clients across the globe. ABN AMRO is committed to innovation and sustainability, actively investing in digital transformation and fintech partnerships to shape the future of banking. With a strong engineering culture, the bank employs hundreds of tech professionals working on cutting-edge solutions in data, cloud, and software development.

🔗 Check out their job board: https://www.abnamro.nl/en/careers/

💡 Want to host a future meetup?

Py.Amsterdam is a community-powered event series, and we’re planning to meet every other month. If your company wants to get involved, apply here 👉Host a meetup

🌍 More info: py.amsterdam
📢 Join our group: meetup.com/pyamsterdam
🐍 Let’s connect, learn, and grow — together!
See you soon! 🚀

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