Ruby developer who goes by 'Chris' because his Polish name is hard for English speakers to pronounce. A regular speaker at wroclove.rb — so much so that he jokes he was 'banned' after doing three or four talks in a row, and was 'unbanned' for 2025. Filled a missing slot at wroclove.rb 2022 with a last-minute talk on shortening the developer feedback loop. Returned at wroclove.rb 2023 with 'Fantastic Databases and Where to Find Them', a tour of SQLite, Postgres, MySQL and exotic databases. Delivered 'Next Token!' at wroclove.rb 2025 — a deep debunking of LLM falsehoods (no chat, no thinking, no tools — just token generation), covering tokenization, stop tokens, reasoning models, tool calling, embeddings/RAG, MCP servers, and structured output, with a survey of the Ruby AI ecosystem. Self-described as a software engineer passionate about performance and making slow things work fast. Has written a gem exposing Postgres' EXPLAIN-based row-count estimation as `estimate_count` without requiring migrations.