Specializing in NixOS Consulting at @ApplicativeSys. C book author, giving university lectures about SW quality @jgalowicz@functional.cafe
Joined April 2012
- Tweets 1,276
- Following 261
- Followers 608
- Likes 2,800
58 Photos and videos
How often it happens that i started to trust Claude because i have seen it writing really smart Nix expressions - to then discover later that it's too lazy to use this capability everywhere when i find bad code again. It's not about model *quality* any longer.
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Jun 15
I've "learned" so many things in my last 10 years of work life that i am currently "unlearning" with the results of making my team and me more effective and efficient.
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May 7
Should we perhaps rename the "main" branch to "initial," since "main" suggests that the others aren't important and thus discriminates against the work of some?
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Jacek Γαλοwιcζ retweeted
Apr 24
New @nixos_org test driver changes from #OceanSprint! 🌊
Better SSH, `qemu.forceAccel` to stop slow fallbacks, and improved logging to cut the noise.
See what’s new: applicative.systems/nixos-te…
#NixOS
ALT Hackers hacking on NixOS at the Oceansprint
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Apr 17
Typical NixOS user with overly customized desktop environment when trying to share the screen over HDMI
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Jacek Γαλοwιcζ retweeted
Apr 17
As we're wrapping up #OceanSprint, I want to do another shout-out to our sponsors, who made the event possible and kept the sprinters fed and productive!
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Apr 17
Effective standups with ~30-40 people in 15 minutes! Thanks to a very disciplined and amazing crowd of FOSS developers.💪
Apr 17
@jgalowicz, founder of @nixcademy, was doing an amazing job narrating our daily standups, as he does with their NixOS trainings.
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Jacek Γαλοwιcζ retweeted
Apr 14
What makes #Nix click for a lot of teams?
At PlanetNix, @jgalowicz pointed out that a lot of teams are focused on moving fast, scaling things, and figuring things out as they go, rather than over-planning everything upfront.
And Nix actually supports that way of working in a very practical sense, because it lets you test complex systems in a way that stays simple, fast, and reliable.
Shoutout to @jgalowicz and @devopsjacquie for a great conversation!
#PlanetNix
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Jacek Γαλοwιcζ retweeted
Apr 12
Award for NixOS tests improvements by @nixcademy at @ocean_sprint
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Jacek Γαλοwιcζ retweeted
Apr 10
You're a scientist in the resistance against The Imperative Empire. An update to your fleet is failing. Identify the anti-pattern!
For an excerpt about this, follow us, comment "anti-patterns" and DM us "anti-patterns".
Turn on notifications to join The Declarative Federation!
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Jacek Γαλοwιcζ retweeted
Mar 14
The @nixos_org integration tests are now faster & cheaper! 🚀 We added a lightweight container backend, meaning you can ditch bare-metal KVMs & run tests on cheap VMs. Plus, GPU testing is now possible! 🔥
Read how it works & try it out here: nixcademy.com/posts/faster-c…
ALT nixos integration tests choo chooo train now with systemd-nspawn container backend. faster and runs on cheap vms!
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Feb 2
We built cool stuff that is currently in review and soon upstream! Let me show you the new NixOS integration test driver super powers at @planetnixconf ! github.com/NixOS/nixpkgs/pul…
Feb 2
🎤 New PlanetNix 2026 speaker!
@jgalowicz will give a talk: Under the Hood of the NixOS Test Driver: Architecture, Containers, and Hardware Passthrough
Sign-up link in the thread 👇
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Jan 19
It's very interesting, that when you negotiate contracts with people, they would say exactly the same things and phrases as described in books about negotiation tactics. It's not only like a skill, but as if people accepted those tricks as rules and adhere to them.
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Jacek Γαλοwιcζ retweeted
24 Dec 2025
Build on Mac. Deploy on Pi. 🛠️
We just dropped the final piece of our NixOS appliance series: Cross-Compilation.
No more hacks. Learn to set up a clean Nix repo to build for ARM/RISCV directly from your laptop.
👇 Read here: nixcademy.com/posts/cross-co…
#NixOS #IoT #Linux
ALT Cross-compilation of whole system images is simple with NixOS
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22 Nov 2025
Procrastinating a bit today with @nixos_org language
ALT Mandelbrot set render with Nix
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Jacek Γαλοwιcζ retweeted
3 Nov 2025
Part 3 of the NixOS appliance series is live! 🔥
Learn how to build self-updating systems with immutable A/B partitions for seamless Over-the-Air (OTA) updates using NixOS and systemd-sysupdate.
Check it out: nixcademy.com/posts/immutabl…
#NixOS #Linux #EmbeddedSystems #OTA #Systemd
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Jacek Γαλοwιcζ retweeted
24 Oct 2025
Boo!—that anti-pattern scared me 😰... I won't make this mistake again, but... will you?
Save your colleagues from it by reposting (before it's too late!).
Fear not, for I can help you become an expert. I will PM you the answer. Just follow us and comment with "anti-pattern".
ALT Can you spot the Nix anti-pattern in this code snippet?
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Jacek Γαλοwιcζ retweeted
23 Oct 2025
Shrink your bloated 1.5GB NixOS images down to ~360MB! 📉
This article shows you how to use `nix-store --query` & `nix why-depends` & `nix repl` to find and eliminate unnecessary dependencies. A must-read for optimizing your builds
nixcademy.com/posts/minimizi…
#NixOS #Linux #DevOps
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9 Oct 2025
The certificates are still handmade. I don't care if it *scales* but it's becoming a *lot* of work lately. 😅
9 Oct 2025
NixOS Training is exploding! 💥
Over 80 certificates 📃 for Nix 101 trainings are being handed out in the next 5 weeks (West & East Coasts 🇺🇸). At least - still getting new orders!
Our mission's pace: What once took a year now takes weeks.📈 The universe wants #Nix! @nixos_org
ALT Over 80 certificates 📃 for Nix 101 trainings are being handed out in the next 5 weeks (West & East Coasts 🇺🇸).
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