Tomasz Kalinowski

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Meet Posit AI.

Built for data scientists who want AI inside their RStudio workflow.

Instead of black-box suggestions, Posit AI helps generate code you can inspect, understand, and rerun.

Learn more:
posit.co/products/ai?...

mirai/dev/skills at main · r-lib/mirai Minimalist Async Evaluation Framework for R. Contribute to r-lib/mirai development by creating an account on GitHub.

New: mirai skill for AI coding agents 🤖

Use with Claude Code/Codex/Cursor for writing async/parallel R code. Covers explicit dependency passing, daemon setup, mirai_map, Shiny integration ++

Install:
npx skills add posit-dev/skills --skill mirai

github.com/shikokuchuo/mirai/tree/main/dev/skills

Rapp 0.3.0 Rapp is an R front-end (like Rscript) that turns simple scripts into polished CLIs, with automatic argument parsing, generated help, and support for commands and installable launchers.

I’m happy to announce Rapp v0.3.0 — a package that makes it easy to build and share polished CLI applications written in R.

Read more: www.tidyverse.org/blog/2026/02...

Should be fixed now! Reticulate needed some internal updates for pandas 3.

A graphic for Posit featuring a hexagonal sticker with a camel carrying boxes and "yaml12" text, over a blue wave background.

Announcing yaml12: High-speed YAML 1.2 for #RStats & #Python 🐫

Built entirely in Rust, get up to 2x faster in R and 50x faster in Python vs. defaults, tag evaluation (like code execution) is opt-in, and strict YAML 1.2 compliance for consistent data.

Learn more: tidyverse.org/blog/2026/01...

It really varies by institution and PI, everyone has their own slight spin on it. This seems like a pretty good starting point that covers the basics well (at least, for a wet-lab context) biotechnology.rutgers.edu/sites/defaul...

quickr recently gained support for OpenMP!
Just add a `declare(parallel())` above a `for` or `sapply()`!

github.com/t-kalinowski...

ragnar 0.3.0 The new release of ragnar adds faster ingestion, new embedding providers, improved retrieval, and new integrations for using ragnar stores from tools.

ragnar 0.3.0 is now on CRAN! 🚀 An R toolkit for RAG from your docs: faster ingestion, better retrieval, Azure OpenAI + Snowflake embeddings, and MCP serving. tidyverse.org/blog/2026/01...

#rstats #rag #ai

GitHub - posit-dev/querychat: Chat with your data in R and Python Chat with your data in R and Python. Contribute to posit-dev/querychat development by creating an account on GitHub.

Sounds like you’re describing querychat github.com/posit-dev/qu...

One pattern I've seen that intuitively makes sense: first ask the llm to generate a draft response, *then* ask it to retrieve documents and fact-check itself, ask if it needs to revise the answer in light of new info, then deliver the final answer.

I agree “looking at code” is squishy. Better code quality is an inevitable byproduct of diligent review, but the key part IMO is it is about continuously reality checking the produced artifact against your intent. It’s the only reliable way to detect when things are going off the rails.

When he (proudly!) stopped looking at the code.

I think it’s when you stop looking at and making effort to understand (and improve!) the code that things go off the rails past a certain size. You have to pay attention and care!

Yes! Performance is very similar between the R and Python interfaces!

Not sure, I’d have to profile it to know. My first guess is that the way extendr protects allocated objects adds some overhead, and if that’s the case, we could probably find a better approach in yaml12.

Retrieval-Augmented Generation: Setting up a Knowledge Store in R Learn about retrieval-augmented generation (RAG) workflows for large language models. This blog provides a hands-on introduction, including example code for creating a working knowledge store using op...

Hallucinations are a key challenge when using large language models in production.

Our latest blog post shows how Retrieval-Augmented Generation (RAG) helps, with a practical R example using open-source tools.

Read more on the Jumping Rivers blog:
www.jumpingrivers.com/blog/retriev...

Some highlights:
- 100% passing on the comprehensive YAML test suite: github.com/yaml/yaml-te...
- In simple-use benchmarks, compared with the most commonly used packages, yaml12 is ~2× faster in R and >=50× faster in Python:
posit-dev.github.io/r-yaml12/art...
posit-dev.github.io/py-yaml12/be...

Fast YAML 1.2 Parser and Formatter A fast, correct, safe, and ergonomic YAML 1.2 parser and generator written in Rust. Convert between YAML and simple R objects with full support for multi-document streams, tags, anchors, and aliases. ...

Announcing two new packages: `yaml12` for R and `py-yaml12` for Python.
Fast, correct, and safe YAML 1.2 parsing and emitting, built in Rust.

R: posit-dev.github.io/r-yaml12/
Python: posit-dev.github.io/py-yaml12/

#yaml #rstats #python

Turn YAML into R and R into YAML with the new {yaml12} #RStats 📦
posit-dev.github.io/r-yaml12/ind...
By @t-kalinowski.bsky.social

On the 📦 website: "YAML in 2 Minutes: A Gentle Introduction for R Users"
posit-dev.github.io/r-yaml12/art...

Shiny for R v1.12 is here with built-in OpenTelemetry support! 🎉

Trace sessions and reactive calculations in production with zero code changes. Just install {otel}/{otelsdk} and set your env vars.

Learn more: shiny.posit.co/blog/posts/s...

#RStats #RShiny #OpenTelemetry

Python Open-Source Developer Posit is hiring a Python open-source developer to create more data analysis tools.

We're hiring an open-source #python developer focused on modeling APIs!

tidyverse.org/blog/2025/11...

#numpy #scipy #scikitlearn

I updated the gist with comments! In short: it configures the container with everything needed to let the agent run `devtools::test()` for the local R package within the container setup time limit. It installs R, configures CRAN, installs pkg dependencies, sets some env vars, etc.

I'd love to know what we can do to make this better! We've put a lot of work into making environment discovery "just work" with `py_require()` recently, but if you're still running into issues then our work is not done!

Add support for free threaded Python · Issue #1847 · rstudio/reticulate Pointing reticulate at a freethreaded Python build currently raises an error. We need to investigate, diagnose the issue, and fix it. We should also make it easy to select a freethreaded Python in ...

I think it will probably be straightforward to add support for GIL-free builds of Python, but it needs a little investigation at the moment. There is an open issue: github.com/rstudio/reti... Contributions welcome!

reticulate v1.44 is on CRAN!

Positron integration is now enabled by default. Enjoy R and Python REPL consoles powered by concurrent threads in the same process, zero‑copy R↔Python data transfer, and full Variables Pane support.

Full changelog: github.com/rstudio/reti...

#rstats #python #pydata

quartohelp/R/store.r at main · t-kalinowski/quartohelp A ragnar-powered application. Contribute to t-kalinowski/quartohelp development by creating an account on GitHub.

Another option is to distribute it via github as a release asset. This would download the store at first use instead of at package install.
Here is an example:
github.com/t-kalinowski...

Work-in-progress #RStats package {brandthis} that enables you to efficiently create themes and color scales from personal/company branding. Uses {ragnar}, {ellmer}, {ggsci} and other R packages.

Setup codex-universal (Codex Cloud) for R package development Setup codex-universal (Codex Cloud) for R package development - setup-codex-universal.sh

For anyone who wants to try Codex Cloud for R package development, here is a setup script you can use:

gist.github.com/t-kalinowski...

The {ragnar} #RStats 📦 has a new function to inspect a data store: ragnar_store_atlas() , which visualizes the store, @t-kalinowski.bsky.social tells #Positconf2025

My Workshop for Ukraine is THIS THURSDAY, 11 Sept! Donate to help medics save lives in Ukraine *and* learn how to query text data with R and the {ragnar} #RStats 📦
Can't make it from noon to 2 ET? Register and you'll get access to recording and materials. Thank you! ❤️
www.machlis.com/workshop/