The second-to-last post[0] talks about how they decided to migrate their stack from Ruby on Rails to Haskell, and are now in the seventh (!) year of that migration.

[0] https://exploring-better-ways.bellroy.com/designing-for-the-...

My first thought was: does that mean they've been actively migrating for seven years, or just "we migrated the most important stuff and can't see any strong business reasons to move some of these microservices that do their job just fine"? But reading the post, it seems the main reason is they no longer understand all the Ruby code!

I thought this couldn't be correct, but... nope:

> We adopted a pragmatic approach: maintain the Ruby code but only port functionality to Haskell when we could add meaningful value in the process. This meant our Ruby codebase gradually became legacy code, maintained but not actively developed. This transition — which we expected to take a couple of years — has now stretched into its seventh year. > > Here’s where the Clean Architecture approach began to work against us. As we hired more Haskell-focused developers and our institutional knowledge of Ruby faded, those carefully crafted abstraction layers became archaeological puzzles. Reverse-engineering what a piece of code actually did — especially complex, multi-step operations with side effects — became a nightmare.

Seems like an insane choice to me

They're based in Collingwood, any Australian would tell you that an n year Haskel rewrite is the most normal thing about them

Speaking as someone from there (Collingwood), we're proudly weird.

Hello from Portland, Oregon!

I'd love to hear more about why you think this is insane.

I'm very happy with my Bellroy Card Sleeve wallet. You know, just in case anyone's checking the comments on a functional programming article for wallet recs. As one does.

My Bellroy wallet is great too.

Also was surprised to see their logo on the blog website.

I have had one of their cardholders for 10 years now, it is incredible how durable and practical that thing is.

And they even use Nix, to add to the craziness.

[0] https://flox.dev/nixinthewild/nix-in-the-wild-bellroy/

Nix isn't so exotic anymore. Every company for which I interviewed about a year ago used Nix

And every person I met today had a parrot on their shoulder. Doesn't really mean it applies to the general public (here meaning most developers out there).

I'd say <1% of all developers world wide have even heard of Nix.

It is used in production much, much more widely than Haskell is, though it remains far from the most common way to do builds or deployments.

So is Costar, the horoscope app, of all things

At least the product is pretty esoteric too.

They must be making a lot of money!

I thought this was a joke about two things having the same name… nope!

One funny thing about software is that beautiful things can emerge from the most unexpected places. I appreciate that there are folks out there with the bravery to share their journey.