It’s pretty annoying that LLMs like to use the construction “X is real”.

A small experiment comparing token efficiency between Haskell and Python. Not rigorous at all but I’ll follow it up eventually. mchav.github.io/a-first-look...

I’ve been doing a small social experiment on how to best to market Haskell (dataframe) to non Haskell programmers. It seems engagement and stars go up when the article doesn’t foreground Haskell but instead uses it as a conduit for a larger concept.

Anyone work with time series data professionally? Either modeling or data engineering? Have some questions and would appreciate a call.

Lake Washington Blvd will be open to people & closed to car traffic every weekend this summer from Memorial Day to Labor Day! The predictable schedule makes it easier walk, bike, roll, along, or drive to the boulevard. Thank you Mayor Wilson, community advocates, and Rainier Valley Safe Streets.

Why do I take this personally? www.reddit.com/r/dataengine...

Using your debt, your search history, and your private data to decide how much you’re worth? Hell no. This is what happens when technology is built to serve profit instead of people. This is why every worker needs a union.

I’ve been thinking a lot about how to scale symbolic regression: this seems like a plausible direction. mchav.github.io/grow-and-mow/

With more and more code being written by AI I think human coding will mostly be for prototyping and brain storming. Notebooks will become a much more important developer interface. So I mixed interactivity, Lean, Haskell, and Python into a single notebook runtime sabela.datahaskell.com

I took a crack at category theory + dataframes. I find the difficulty with reading and writing about this kind of stuff is that it's really hard to communicate what the "point" is. Hopefully it all makes sense: mchav.github.io/what-categor...

I've been looking at symbolic regression for some time now. I think most genetic approaches would benefit from large e graph databases to reduce the search space. Having to start every search from scratch every time seems silly.

Today is a great day for some major news! DataFrame v1.0.0.0 has been officially released! Step up your exploratory data analysis in #Haskell with Typed data frames, direct connection to HuggingFace data sets, and Python integration through Apache Arrow. discourse.haskell.org/t/ann-datafr...

Anyone know what could be a good second career? Even if coding makes it out of the AI era I fear it won’t be interesting.

Started a new position @coreweave.bsky.social working on @marimo.io

Sometimes you gotta do the boring thing that gets the job done. www.datahaskell.org/blog/2026/03...

Sabela - A reactive Notebook for #Haskell by the DataHaskell project Announcement: discourse.haskell.org/t/ann-sabela... Github Repository: github.com/DataHaskell/...

I gotta starting taking cold showers before a job interview for a job that I want - wash off the smell of desperation.

Small experiment: treat feature engineering as program synthesis, then use an LLM as a lightweight prior over which derived quantities are “nameable.” The learner stays classical; the artifact gets way more readable. mchav.github.io/learning-bet...

Symbolic AI is built on the premise that models should be presented in terms that are understandable to us. When you interact with a symbolic system you learn something about the reality that it tries to model. That alone makes symbolic approaches worth betting on in the long term.

All is data science www.datahaskell.org/blog/2025/12...

In software it’s often important to distinguish between solving the scientific problem (how do we make this generalize for all instances of the problem) versus the engineering problem (how do we make this work for the environment we anticipate it’ll be used in).

Great article! The fix also really outlines that contributions don’t have to be hundreds of lines of code to be impactful.

Just updated the dataframe SQL library to auto generate expression bindings from the table types. The read input surface is looking pretty great now: CSV, JSON lines, Parquet and now various SQL DBs. hackage.haskell.org/package/data...

The State of #Haskell 2025 survey is out! Please take ~10 minutes to fill this out and share it with friends/colleagues/coworkers, whether or not they are users of Haskell.

Learning how to do the necessary but boring skill is underrated. It pays off so much in the long run.

Layoutz – A tiny zero-dep lib for beautiful #Elm-style TUI's in #Haskell 🪶 flora.pm/packages/@ha... www.reddit.com/r/haskell/co... discourse.haskell.org/t/layoutz-0-...

Perhaps you saw the post series "Python is not a great language for data science"... well, here's Haskell IS a Great Language for Data Science https://jcarroll.com.au/2025/12/05/haskell-is-a-great-language-for-data-science/ #haskell :haskell: #rstats :rstats:

Great article that gives a quick run through of Hasktorch. www.stackbuilders.com/insights/has...

Article to checkpoint where we are with the Haskell Jupyter kernels. www.datahaskell.org/blog/2025/11...

There’s something beautiful at the end of all this. I just know it.

Continuing the series on program synthesis: mchav.github.io/an-introduct...

As cultural beings, we are echoes of the past: even our most personal thoughts, emotions, and experiences are mediated by words, images, and ideas we inherited from previous generations. Your mind was born and started growing many thousands of years before your body.” Francois Chollet

Wrote a new article where I checkpoint the work we’ve done so far enabling Kaggle style EDA-to-model workflows in Haskell. Covers Jupyter notebooks, dataframes, charting and machine learning with the iris dataset as the working example. mchav.github.io/iris-classif...

Lorem ipsum is taken from an excerpt about stoicism which says: “The wise man, therefore, always holds in these matters to this principle of selection: he rejects pleasures to secure other greater pleasures, or else he endures pains to avoid worse pains.”

Swiss insurer La Mobilière refactored their risk model to Polars, achieving 5-10x speedups and enabling actuaries to run millions of simulation years on laptops. A scale previously unfeasible with pandas due to memory and single-core limitations. pola.rs/posts/case-m...

The MIT program synthesis class finally has problem sets. I’ll dedicate most of the fall/winter to completing it. people.csail.mit.edu/asolar/Synth...

There are a lot of things I wish I had the discipline to learn over the years. I convinced myself I needed the right mentor or book. Years later, more has been lost from indecision than wrong decision.

Rebooting the work started by @ocramz.bsky.social with dataHaskell Come through: discord.gg/UXcv5Eaz

“When a full-service grocer leaves a neighborhood, it doesn’t just take away a shopping option; it reshapes the local food landscape. Competition shrinks, which means prices rise and choices narrow. Families end up paying more whether they stay local or spend extra time and money traveling farther.”

Everything is converging to the same syntax.

Doing important things with AI is misguided. We use tasks to build context. That context begets creativity and problem solving in the future. Doing stuff is both a creational and transformative process. AI is faster but using it undercuts the most important investment you could make in your task.

Samthing Soweto to start the morning youtu.be/42mq448-arg?...

Have some pretty cool examples of feature engineering using program synthesis on Haskell data frames. Give a function space, we run a breadth first search to find what functions (and their compositions) have the highest correlation with a target variable. github.com/mchav/datafr...

#AmeriHac – The hackathon by the #Haskell Foundation in New York City has been announced for the 7th and 8th of February 2026! discourse.haskell.org/t/the-inaugu...

Starting a series on program synthesis: mchav.github.io/an-introduct...

Starting my foray into program synthesis and data wrangling. Currently trying to implement some interesting papers.

Check out @andrewlamb1111.bsky.social 's talk at the recent Iceberg meetup for a condensed overview of the the new Variant type coming to Parquet #apacheparquet #apachearrow

Considering deleting my LinkedIn. I’ve never liked the app and it’s kind of a cesspool.

I asked ChatGPT to roast me and it actually hurt my feelings. lol.

This was a pretty good side mission.