Is Elixir and Phoenix a good choice for real time trading systems?

IMO yes! It’s possible to treat offers as processes & index them to get really fast matching. Use commanded if you need event-sourcing for auditability.

It depends on your definition of real time. Erlang is quite popular in real time ad exchanges. Lack of garbage collection pauses give more predictable latency than some languages. It is considered “soft” real time, though.

When things need to be really fast and predictable, then C++ was popular, sometimes supervised by Erlang. That is a pretty good approach, isolating the pieces that need to be fast. Now speeds are such that things are done in silicon.

We wrote an embedded “logo inserter” box for the broadcast television industry in a mixture of Erlang and C++. The C++ handled the low level processing: pull a frame from a Blackmagic SDI interface, add an image, send it out another interface, 60 frames per second. Erlang handled everything else, and restarted the C++ if it should crash in time for the next frame. Bulletproof.

Thanks @jakemorrison and @AndyL.

Does Elixir with Phoenix is good choice for real-time stock trading systems ?

Depends on what you mean by this. I’ve heard success stories with c++ and erlang (c++ handled computations, erlang handled some networking). And some experiments with erlang + rust (now rust handles the computations).

I don’t quite see how phoenix fits in a trading system, though.

Low latency can mean a second to some people, and a millisecond to others. What range do you have in mind?

@dom Trading system placing buy/sell equity or FX orders to the market will target a latency of under 20ms

That sounds quite doable. Keep in mind that Erlang is optimized for robustness above math performance, so it lacks things like native integers (it uses bignums) and can be slow. If your system is computation-heavy, managing big baskets, etc. that may be a worry. NIFs may help. For stuff like order routing and as a backend for user GUIs though it should be a nice platform to work on.

Take a look at https://chaince.com/, it’s a crypto exchange which written by Elixir.

@dom and @gonglexin Thanks for your feedback’s.

I would think that from the point of view of a market maker, a real exchange and a crypto exchange are very different beasts in terms of response time / performance requirements … I think even ads (see adroll) come closer to what’s required from a real time system than a crypto exchange due to the inherent limits of crypto trading (which seems to be mostly retail for now).