Tomasz Kalinowski

I build open-source tools for data practitioners and lead an engineering team at Posit.

I build open-source tools for data practitioners and lead an engineering team at Posit. My work spans R and Python, machine learning, and tools for AI agents.

Selected writing

• ir 0.1.0: self-describing R scripts and Quarto documents

  Keeping a script’s R version and package requirements with the code that needs them. Posit Blog · July 2026 · with Christophe Dervieux and Charlie Gao

• Introducing Keras 3 for R

  The rebuilt R interface to Keras, including changes to the API and documentation. Posit Blog · May 2024

• Generalizing Support for Functional OOP in R

  Changes to R that help S7 and other object systems work with existing method dispatch. The R Blog · May 2024 · co-authored

All writing

Selected work

• reticulate — I maintain a package for calling Python from R and passing objects between the two languages.
• MCP Console — I develop an interactive runtime for AI agents working with R, Python, and SQL.
• quickr — I built a compiler for R functions with type and shape declarations.

More about my work