You should explain what did not work with Julia since there is extreme likelihood the situation will be worse with Carbon, given Carbon is just getting started. The best option might be to stick with Python (or C++)
I don't know what OPs project looks like, but in our company the choice has a clear path: - performance/low level: Rust, Cpp
- CPU/memory is not the bottleneck and I don't need much concurrency / it's data science, machine learning, ETL ... : Python
- concurrency is key, highly distributed system: elixir, golang, erlang
- programming based on mathematical models: Haskell