- Lead DeveloperSlovensko.Digital2015 - PRESENT
- Led a small team of developers and freelancers to build parallel, low cost e-government services.
- Created a platform for downloading/cleaning public open data sets with millions of entries and gigabytes of data.
- Build a fast autocomplete search based on Elasticsearch.
- Managed multiple servers serving staging/production environments with Docker-based deployment.
- Supported various tools needed for business (Trello, JIRA, email servers, billing, AWS).
Technologies: Ruby on Rails, Elasticsearch, PostgreSQL, JIRA, AWS - OwnerMinio, s.r.o.2011 - PRESENT
- Created a platform for scraping various public government registers and databases.
- Built a platform for automatic data disambiguation, cleaning, and reconciliation of multiple messy public datasets.
- Managed traffic/performance analytics for several projects.
- Built a platform for making government contracts transparently available for anyone in Slovakia.
- Managed a search engine with 600K+ documents (TBs of raw data).
- Organized a monthly polyglot developer meet-up in Bratislava every month since 2011.
- Created a system for fraud detection in European Social Fund project proposals.
Technologies: Ruby on Rails, PostgreSQL, Elasticsearch, Redis, JavaScript - Senior DeveloperSearchD/Luigi's Box2013 - 2015
- Created a scalable log processing pipeline analyzing millions of events.
- Designed advanced metrics and reports for testing and evaluation of real-world search engines.
- Worked on the full stack, from business goals through front-end tuning to back-end development and tuning.
- Ensured high code quality by enforcing automatic testing on the build server, code coverage trend reporting, and code reviews.
- Proposed and successfully implemented business process changes to optimize signup and onboarding funnels, yielding an increase in goal conversions.
Technologies: Ruby on Rails, Elasticsearch, Redis, PostgreSQL, SaltStack - Senior Back-end DeveloperSynopsiTV2011 - 2013
- Created a recommendation engine for movies and TVshows.
- Built a logging and quality evaluation platform for a recommendation engine and search-related sub-projects.
- Proposed and measured several UX exhancements.
- Created a crawling service scraping data from various online sources.
- Implemented various duplicate matching algorithms for cleaning and disambiguating data.
Technologies: Ruby on Rails, Elasticsearch, Redis, PostgreSQL - FounderFoaf.sk2010 - 2012
- Created and sold a project to download, clean, and update data about over 300k companies and 500k people from the official registers of Slovak companies, public procurement, debts, internet domains, and other public data.
- Supported a complex site handling over 500k page views a month.
- Created a framework for scraping, cleaning, and merging messy datasets.
- Built various visualizations and aggregation reports from gathered data.
- Fine tuned autocomplete search for highly relevant instant responses.
Technologies: Ruby on Rails, MySQL, Sphinx - Researcher, PhD StudentFaculty of Informatics and Information Technologies2008 - 2011
- Built a news recommendation engine for the largest Slovak newspaper peaking at 3k+ rpm.
- Created and led a new course on web development.
- Published multiple articles on recommendation systems and data mining.
- Led multiple teams of students.
- Built and supported various faculty sites.
Technologies: Ruby (on Rails), R, SQL - ContractorFreelance2001 - 2011
- Built a "did you mean?" search feature for a major music website in Slovakia.
- Built and maintained web applications for various SMEs.
- Consulted several clients regarding SQL performance fine tuning.
- Created a popular random text generator for designers.
- Handled basic HTML/CSS work for various clients.
Technologies: PHP, Ruby on Rails, JavaScript, MySQL, PostgreSQL
