Maciej Krajowski
CTO at platformOS
Warsaw, Masovian Voivodeship, Poland
Summary
👤
Senior🎓
Top SchoolMaciej Krajowski is a pragmatic CTO and seasoned full‑stack engineer with 13 years of experience building scalable web platforms, currently leading platformOS from Warsaw. He specializes in backend systems and developer productivity, championing test-driven practices and having driven practical process improvements (introducing staging, tests and Git) across several teams. His career spans building peer-to-peer marketplace platforms and high‑availability Rails systems, with hands-on experience across Ruby on Rails, Grails, PHP and modern CI workflows. Known for turning complex product requirements into maintainable, extensible code, he balances technical leadership with day‑to‑day engineering. Outside work he’s unusually social for an engineer—an avid dancer and multisport competitor—bringing team energy and discipline to engineering culture.
13 years of coding experience
10 years of employment as a software developer
MSc, Computer Science, MSc, Computer Science at Danmarks Tekniske Universitet / DTUBS, Computer Science: Software Engineering, BS, Computer Science: Software Engineering at Wyższa Szkoła Informatyki Stosowanej i Zarządzania WIT w Warszawie
English, Polish, German
Github Skills (44)
bootstrap-select10
documentation10
bootstrap9
raygun9
activemodel9
ruby-on-rails8
sinatra8
marketplace8
form-objects8
shared8
rails8
ruby8
error-reporting8
error-handling7
linux7
Programming languages (8)
Github contributions (5)
Platform-OS/pos-module-tests
Sep 2023 - Jan 2025
Contributions:2 reviews, 5 PRs, 6 pushes in 1 year 4 months
Slashek/bootstrap-select-rails
May 2013 - Oct 2019
bootstrap-select-rails
Contributions:23 commits, 12 PRs, 8 pushes in 6 years 5 months
ruby-on-railsbootstrap-selectrailsrubybootstrap
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