> And because Bonsai is written in OCaml, it becomes possible to use the same language and types on both the backend and frontend.
Finally! I was waiting for this to become possible!
Not sure why, but reminds me of Fog Creek's Wasabi.
Looks like it's Web-only, no mention of the native UI support (terminal UI excluded).
There's a full terminal implementation of Bonsai as well. I actually use it in my personal workflow these days to manage my contacts database! https://anil.recoil.org/notes/aoah-2025-9
Unrelated but what do you use to manage your personal website? I love how everything is interconnected.
This would of been cool back in 2014.
All your money and retirement funds are safe; I’m too dumb to work at JaneStreet; every time I see OCAML I feel less than and confused.
I wish there were more OCaml shops out there
Oh it needs a userland trampoline!
> JSOO does not have tail call optimization
The "Why Bonsai?" I found really funny.
Let me re-write that section for you:
Why Bonsai?
At Jane Street we're super excited by Functional programming and by CAML in particular, so when we need low latency software, we use OCAML, when we need hardware, we write out own langauge - HardCAML, and when we need a Web UI, we build a Web UI framework in CAML. Because we fucking love CAML.
Agreed, looks like it's reinventing the wheels. Frameworks does not really matter today, AI agents write the code anyway.
But AI do benefit a lot from a strict compiler, and having a simple language improve a lot on type-safety, so I don't think it is to throw, even today.
But what about compilation speed? Hot reload? Maintainability? What is the bus factor for these kind of technologies?
Yea, its cool to have strict type safety, but what's the point of it doesn't have all the benefits from other Frameworks that took years to polish
JaneStreet has enough free cash to not worry about those issues. If one of their key persons dies in service, they can go out and contract the worlds leading expert in that domain, and their annualised rate isn’t even a rounding error on their bottom line.
AI certainly writes Internet comments so that the flock does not have a single minute to get independent thoughts.
Better frameworks will still help AIs avoid silly mistakes. A smarter framework means you can be productive with a dumber/cheaper AI.
Similar attempts include Scalajs.
The general challenge becomes integrating the fractional front-end code written in your backend-language that compiles to JS with the rest of the JS ecosystem.
JaneStreet have a love of writing their own stuff from scratch so it doesn't apply to them but it might to you.
Hence most people end up with frontend-as-backend rather than backend-as-frontend.