Hi! My name is Paweł. I’m a web developer from Poland and welcome to my digital garden! I am an Elixir developer with a lot of Ruby history. Therefore a lot of my articles are about these technologies. I also occasionally write about PostgreSQL, testing and programming in general.

About me

• Location: Wrocław, Poland
• Github: katafrakt
• Social media: genserver.social, ruby.social, BlueSky
• Stack of choice: Elixir/Phoenix, PostgreSQL, LiveView or Vue
• Cats: 2

My favourite articles

• Understanding complex Ruby application with profiling tools
• Hidden jewels of Ruby stdlib
• There’s a gem for this or how we got spoiled by the ecosystem
• Snowflake method for software projects

Latest articles

• On validations and the nature of commands (05 Feb 2025)
• Booleans Are a Trap (09 Nov 2024)
• Chekhov's gun principle for testing (01 Nov 2024)
• Mruby: Errors in Ruby code and how to find them (06 Oct 2024)
• Mruby: Beyond "hello world" (05 Oct 2024)

TILs

• Update git dependencies in mruby (25 May 2025)
• Inspecting compiled Elixir code (18 Dec 2024)
• Return simple values from Oban job (09 Dec 2024)
• Two ways to ensure no NULLs in PostgreSQL (02 Dec 2024)