Oskar Szrajer

Ruby Programmer & Web Developer

Experience

  • Founder / Owner

    Gotar

    Apr 2011 – ongoing Gdynia, Poland / Remote
    • Founder and owner of Gotar, a one-man Ruby/Elixir consultancy specializing in web development
    • Developed numerous web applications and systems for clients worldwide
    • Serving as business consultant for Rebased Software House

  • Senior Software Developer

    Impactpool

    Sep 2021 – ongoing Remote
    • Helping Impactpool with software development and building/leading the tech team. Impactpool is a Ruby on Rails 8 platform connecting humanitarian employers with qualified talent, featuring job matching, talent pools, analytics, and integrations with BigQuery and external APIs.
    • Utilized modern Rails tools including Hotwire (Turbo and Stimulus) for dynamic interfaces, ViewComponents for reusable UI elements, and Stimulus controllers for enhanced interactivity.
    • Integrated advanced technologies such as Puppeteer for web scraping, Dry-rb for business logic, and Sequel ORM for database management.

  • Senior Backend Developer

    Belighted

    Oct 2018 – Aug 2021 Remote
    • Hannah Online – backend for financial forecasting app (Rails, Ruby, Dry-rb, RSpec, PostgreSQL, GraphQL)
    • AXS – backend for car sharing platform (Rails, Ruby, Dry-rb, RSpec, PostgreSQL, External APIs, SOAP)
    • Admeet – backend for GDPR generator (ROM, Roda, Ruby, Dry-rb, RSpec, PostgreSQL, GraphQL)
    • Helping company to grow

  • Co-owner

    Ragnarson

    Jul 2014 – Oct 2016 Sopot, Poland / Remote
    • Established Tricity office branch
    • Contributed to company growth from 10+ to 30+ developers
    • Hired and trained new developers, including over 100 interns
    • Supported clients as Project Manager and Account Manager

  • Senior Ruby Developer

    Ragnarson

    Apr 2011 – Jun 2016 Sopot, Poland / Remote
    • Getmii – Geo-based instant messaging backend system (API for mobile iOS and Android apps) (ROM, Roda, Ruby, Dry-rb, RSpec, Postgres, ElasticSearch, REST API)
    • Masii – Credit Cards & Insurances comparison platform (ROM, Roda, Ruby, Dry-rb, RSpec, Postgres, REST API)
    • Locafox – Geo-location price comparison platform (Ruby, Roda, PostgreSQL, ElasticSearch, RSpec, REST API)
    • MaMyMo – high-performance backend system supporting Google Ads platform management(JRuby, Threads, Sinatra, PostgreSQL, Redis, RSpec)
    • Teon – Car manuals (Ruby, Rails, ActiveAdmin, MongoDB, RSpec)
    • Tripsta (TravelPlanet) – high-performance support systems (>3000 req/s) (Ruby, Goliath, Sinatra, Redis, RSpec)
    • Bellegs – Spree-based e-commerce platform (Spree, Rails, RSpec, PostgreSQL)

  • Web developer, DevOps

    Renault Trucks (Bernard Trucks)

    Aug 2006 – Sep 2010 Gdynia, Poland
    • Built and managed Linux-based servers
    • Built company website using PHP and SQL
    • Built internal software using PHP and SQL

  • Web developer, DevOps

    ITM Centrum Komputerowe

    Apr 2006 – Jul 2006 Gdańsk, Poland
    • Built company website using PHP and SQL

  • Lecturer

    ITM Centrum Komputerowe

    Dec 2005 – Jul 2006 Gdańsk, Poland
    • Lecturer on professional courses including Linux System Administration, Flash (ActionScript), Photoshop, and PHP

Volunteer Experience

  • Open Source Contributor

    Various projects (details on GitHub)

  • Speaker

    TRUG, Wrocław.rb

  • Lecturer

    University of Gdańsk (Ruby, Elixir)

  • Mentor

    Rails Girls Łodź & Tricity

  • Founder

    TRUG – Tricity Ruby User Group

  • Judge

    Ruby Rampage