Indeed, an advanced static compiler could provide assurance against certain types of errors. Generally, I think compilers should do as much work as possible, because people are slow and prone to error.

Having said that, I know of no language that offers concurrency via the actor model – which is easy to reason about – fault tolerance, advanced static typing and distribution out of the box, all at the same time.

Thus, I'm wiling to forgo the static typing, in favor of all other features.; no to mention other cool Elixir/Erlang features such as live runtime introspection and tracing, hot code reloading, the OTP, excellent multicore support, and soft-realtime capabilities due to preemptive scheduling and per process garbage collection.

And btw, people have written large systems in languages less stricter than Elixir – e.g. Python, Ruby, etc - thus I think large codebases in Elixir should be fine.