About

Backend engineer at Productive. I work on the sales side of the application with the CRM team and on app-wide performance optimizations with the Platform team. Ruby on Rails & MySQL.

MSc in Computer Science from FER, 2026. Occasional contributor to ruby-lsp, ruby-lsp-rails and rubocop-rspec.

Writing

The column you never render still costs you

2026-10-12

A list that shows just a title and a date took thirteen seconds, because MySQL read the transcript of every call it walked past. Why it happens, and four ways out.

MySQL can't merge sorted index ranges (and the UNION ALL fix)

2026-07-23

An IN filter with one value is fast. Add a second value and MySQL scans the whole table. Why it happens, and the UNION ALL fix.