Time to recap what I’ve been up to lately. Admittedly this post is a bit overdue1, but there has been a lot on my plate lately and I had little time for blogging.


Dutch Clojure Days

The most interesting thing I’ve done on the Clojure front recently was speaking at the Dutch Clojure Days conference. I spoke there about nREPL’s revival, future and importance. I think the talk went well and resonated with the audience. I even got an unexpected promise of financial backing for the project by Siili!

Here’s the slide deck from my presentation. I hope the recording of the talk will become available soon.

I think it was a great conference overall and I’m happy I got the opportunity to be a part of it. I certainly hope that I’ll find my way back there, even if I’m just a regular attendee. I have to note that even though the conference was completely free it was organized really well! You could clearly tell that it was a product of love and passion and that’s the only real recipe for a great conference!

By the way, Josh Glover recently wrote a nice summary of the conference.


There’s not much to report here. The most important thing that happened was the decision to make op names strings internally. This simplified the implementation of the new EDN transport and make the code simpler overall.

I’ve also updated the nREPL section in Lambda Island’s guide to Clojure REPLs to reflect the recent nREPL changes.


On Orchard’s front the big news is that we’re very close to getting rid of almost all third-party dependencies the project currently has - namely tools.namespace and java.classpath. This happened as the side-effect of work to address dynapath-related issues on Java 9+. You can learn more about all of this here. Once we wrap this up, I’ll cut Orchard 0.5 and we’ll focus our attention on Orchard 0.6 and the huge milestone of merging ClojureScript support into Orchard (and deprecating cljs-tooling in the process).

Fun times ahead!


I’ve finally found a bit of time to work on CIDER.

My current focus is getting more functionality working without cider-nrepl. The biggest step in this direction was implementing an eval-based fallback for cider-var-info - a function which powers definition lookup and doc lookup (amongst others CIDER commands). You can read more about the scope of that task here and I’d certainly appreciate some help with it.

On a related note - I can’t wait for us to implement client dependency injection in nREPL itself, as it would simplify that functionality tremendously.

In other news - I fixed a long-standing problem with checking for the presence of required ClojureScript dependencies before starting a ClojureScript REPL, but at this point I’m thinking that probably this whole dependency validation idea was a bad one and I should just kill those checks completely.

I’ve also looked into a compilation error highlighting regression caused by changes in Clojure 1.10. It’s a trivial problem, but Emacs Lisp regular expressions have a very messed up syntax that makes it really unpleasant to work with them. Here’s the regular expression in question:

(defvar cider-compilation-regexp
  '("\\(?:.*\\(warning, \\)\\|.*?\\(, compiling\\):(\\)\\(.*?\\):\\([[:digit:]]+\\)\\(?::\\([[:digit:]]+\\)\\)?\\(\\(?: - \\(.*\\)\\)\\|)\\)" 3 4 5 (1))
  "Specifications for matching errors and warnings in Clojure stacktraces.
See `compilation-error-regexp-alist' for help on their format.")

How many things do you need to escape???



Only 5 days after DCD I did a second talk at the RubyDay conference in Verona, Italy. I spoke about Ruby 3 there and you can check out my slide deck here. Funny enough, a lot was said about Ruby 3 on RubyKaigi just a week after my talk. I’m pretty glad that I was spot on with most of my predictions though, despite the limited sources of information I was working with.

You’ve got no idea how stressful it is to work on two new talks for back-to-back conferences! I was so relieved after I wrapped up my RubyDay talk! And I’m never doing this again.2

Apart from the stress RubyDay was a really nice event and I had a lot of fun meeting the local Ruby community. The conference was also a nice excuse for me to travel around Verona and spend a week enjoying Italian food and wines.


RuboCop saw a ton of activity lately and an important new release, which improved a lot its pretty-printing capabilities.

RuboCop 0.68 is already right around the corner and I’m really excited about getting some line length autocorrection support in it. That’s going to be a massive improvement in the formatting department.

I was also quite pleased to see what Flexport are doing to push this even further! I’m really grateful to see them making their work open-source and contributing it upstream!


I continue slowly with my Haskell explorations and I’m having quite a bit of fun overall. Nothing interesting to report, though.


I never met Joe Armstrong in person, but I’ve always admired his work and he was a big source of inspiration for me. I was really saddened by the news of his passing on Saturday and I want to take a moment to honour his memory. I’ve often pondered on the legacy of software engineers, as things are some transient and ephemeral in our line of work. I have no doubt, however, that Joe’s legacy will live on for a very long time and his work will continue to inspire software engineer in the years to come!

Rest in Peace, Joe! You’ll be missed, but not forgotten!

Real World

It was really nice to spend some time in Amsterdam and Italy around the two conferences. I finally managed to visit Milan and the nearby Lake Como, after planning to do so for ages, and they didn’t disappoint. I can also heartily recommend to everyone to spend some time in the nearby town of Bergamo (where most low-cost airlines bound for Milan tend to land).

I’ve started reading “Persepolis Rising” (the seventh book in the “The Expanse” sci-fi series) and so far I find it to be pretty disappointing. Generally I’ve noticed that most book series really struggle to keep their momentum past volume #3.

On the movies side I finally watched “Baby Driver” and I certainly enjoyed it a lot. The movie’s style and soundtrack are quite something and felt very refreshing to me! Yesterday I went to see “Pet Sematary” and it was so-so. I think I liked the first movie better (even if I can barely remember it at this point). This was a reminder I should probably read the book one of those days. Later today I plan to hit the movies again with “Shazam!”. Fingers crossed!

As usual, I wanted to do many other fun or healthy things, but I miserably failed. Better luck next time!

  1. I was hoping I’d write one each week. 

  2. Although I’ve promised this to myself in the past as well.