The whole build gets quite complex. Numba is interesting but also still a bit limited in what it supports. There are no silver bullets and sometimes you can find a good fit, but IMO the JVM or C#/.net overall have a better story when it comes to write performance critical applications (but don’t need to get the last 20% such as HFT or HPC sims), as you can also find people on the market who understand how to do and maintain that more easily. There are tons of python devs but in my experience at least on European market their understanding of underlying systems tends to be limited.