unison VS lawvere

Short version: no type classes (yet)

Longer version:

Building upon what Quekid5 mentioned, Unison abilities are an implementation of what is referred to as algebraic effects in programming language literature. They represent capabilities like IO, state, exceptions, etc. They aren't really a replacement for type classes, though in some cases you can shoehorn abilities in where you might otherwise use a type class.

For someone coming from a Haskell background, I think that abilities are closer to a replacement for monad transformers. But in my opinion they are much more ergonomic.

Discusson of type classes comes up a lot. Here is a long-standing GitHub issue: https://github.com/unisonweb/unison/issues/502

For what it's worth, I've written Unison quite a lot over the past few years and while I've missed type classes at times, I think that reading unfamiliar code is easier without them. There's no implicit magic; you can see exactly what is being passed into a function. So far I've been happy with a bit more verbosity for the sake of readability.

I've been following the Unison lang [1] for quite some. Wing seem to set similar goals? From the first glance Wing looks more polished, but there's "The Big Idea" behind Unison - is there something similar?

[1]: https://github.com/unisonweb/unison

in haskell it looks like this, you specify the language extensions you want at the top of the source files: https://github.com/unisonweb/unison/blob/trunk/unison-core/src/Unison/ABT.hs

they adjusted my ticket to be a bug fix on their part.

I think Unison is going in this direction. Imo this is a mistake, as a program language functions not just as specification for the machine, but also as communication between programmers. Allowing the introduction of arbitrary dialects to suit individual preferences seems like it would interfere with that communication.

I don't really know much about this area, but there's a language literally called Lawvere.

https://github.com/jameshaydon/lawvere

Yes that is absolutely the idea. Even for pure-programming, the idea is to define categories via sketches, to define functors between the generated theories, and to use this to somewhat solve the extension problem. This is somewhat explained here: https://github.com/jameshaydon/lawvere/blob/master/examples/presentation.law.md but I'll pad it out soon.