Lead full-stack engineer with 20+ years of shipping production software, mostly Ruby and Rails (since 2007). I move fast on new product work and keep mature codebases healthy as they grow, several Rails majors later. Lately I've been doing a lot of agentic engineering: building architecture, docs, and checks that steer AI agents toward code I'd recognize as my own. Fully remote from Poland.
Currently Lead Engineer at Plane (YC W17), a global payroll and HR platform.
- Gunfinger – Rust CLI that finds tracks from your own collection inside DJ mixes, using acoustic fingerprinting that follows vinyl pitch shifts and key-locked tempo changes
- Digga – Dig Discogs by ear. Local-first, keyboard-driven crate digging: audition vinyl through YouTube, build your DJ collection, and find forgotten tracks
- Leshy – PII scrubber for logs, JSON, and debugging data. A local NER model catches what regexes miss, and nothing leaves the woods
- Setcast – turns recorded DJ sets into video:
mix.mp3+ tracklist + cover art = an audio-reactive MP4, ready for YouTube
Vibe coded? Nope, agentically engineered!
- quicksand.js – vintage jQuery plugin for animated filtering and sorting (~1.8k stars)
- razorjack.net – personal site and blog, built in Astro
- dotfiles – 14 years of tooling refinement
Long-form on Ruby, Rails, and DSLs at razorjack.net:
- Fifteen Ruby takes on a stepped-worker DSL
- Railsmaxxing, or hidden Rails gems
- An RSpec-like test DSL in Ruby, from scratch
- Playing with Ruby object model: prototypal inheritance
- Implementing DSL in Ruby, part 1: CSV importer
Outside of code: gaming, music production, synthesizers, guitar, mixing. Black/death metal and techstep/neurofunk/jungle.