Any sufficiently complicated concurrent program in another language contains an ad hoc informally-specified bug-ridden slow implementation of half of Erlang and OTP.
Virding's First Rule of Programming
Avoid microservice envy and start with one or two services before rushing headlong into developing more, to allow your teams time to adjust and understand the right level of granularity.
People are bad at predicting the performance of complex systems [...], our ability to create large and complex systems fools us into believing that we're entitled to understand them.
Carlos Bueno, Mature Optimization Handbook