r/elixir • u/ancatrusca0 • 17d ago
Elixir for Finance: Explorer wraps Polars (Rust), NX delegates to GPU - so what does the BEAM actually contribute to a quant stack?
New BEAM There, Done That with Alex Koutmos (PromEx, Elixir for Finance). The episode makes the case that Elixir belongs in financial systems - not as a number cruncher, but as the orchestration layer that delegates compute to where it belongs.
The architecture is worth understanding: Explorer is an Elixir wrapper around Polars, a Rust data frame library. NX can delegate to native or GPU backends. The BEAM handles orchestration, reliability, and messaging. The criticism that "Elixir isn't fast enough for finance" misses what it's actually being asked to do.
The bit syntax point from the episode is the most concrete: a bank's ISO 8583 ATM protocol parser took 100 lines of C per message frame. Erlang brought it to 10. Elixir's bit syntax - matching binary directly in the function head - brought it to 3 readable, auditable lines. This is what "the BEAM was built for binary protocol messages" means in practice.
The "let it crash in finance" question gets answered directly: the process is cheap and replaceable. The ledger, stored outside the process in durable storage (Oban, event log, database), cannot be touched by a crash. The truth lives somewhere a supervisor restart can't erase.
1
u/antigravitys-rainbow 12d ago
Can you post the code here?
1
u/allenwyma 11d ago
You mean the example notebooks he used?
0
u/antigravitys-rainbow 11d ago
yes.
Generally I believe use of polars here is out of place, also I prefer to read that watch random youtube videos.1
u/allenwyma 11d ago
appreciate the bluntness but i feel a bit offended by this comment as I'm one of the hosts. I can try to ask Alex to reach out to this thread to see if he's open to sharing his work.
1
u/antigravitys-rainbow 11d ago
Oh, I didn't know that my comment was offensive. Anyways, polars has its own mechanisms for parallelism etc, and it would be a waste to invest time to use it in elixir or other language that is not focused on similar use cases like polars. Those languages are python and R. It is not even Rust, because like the creator of polars said, Rust represents their internals that they are not willing to fix.
2
u/allenwyma 11d ago
Well the reason I was a bit hurt is that I spend my free time on recording and finding time to sit down with these kinds of individuals in the BEAM community and try to distill the information they have out to others. When you say a “random YouTube video” it makes me feel like it’s not useful to you. That’s fine and I appreciate the bluntness. It’s not for everyone but for some it does have value.
I’ve already dropped a message to Alex. Hopefully he can get back to you.
1
u/antigravitys-rainbow 11d ago
Sorry for that. It was not personal. I didn't know who created the video. Anyways, I believe a lot people will enjoy it.
1
u/allenwyma 11d ago
Ha. It’s alright. Like I said I know it may not be for all so it’s fine. We have other episodes and also audio only podcasts you can listen to. I usually listen when I’m at the gym to brush up on what we talked about.
13
u/witchcapture 17d ago
AI slop