[tomkwong]

I have a working situation where I need to work with Python and Julia. I'd like to say that there are great interoperability between these runtimes, so you can easily call a Python function from Julia and vice versa.

Clearly, if you find Julia more productive and think that's the future, then that's great! There is no reason to hold back given that you can call out to legacy Python code as needed.

The downside, obviously, is that you have two languages to work with, which is not ideal. Depending on the size of your project and how much appetite you want to migrate code in your longer term roadmap, you can make a good judgment how to proceed.

I would have to say the world needs to move forward no matter what. COBOL used to be the best language for business applications and it clearly went out of favor. The recent events with COVID-19 brought up a clear technical debt issue. What I' trying to say is, sooner or later, the code will need to be rewritten.

Google tends to rewrite their software every few years to keep it fresh. That's not a bad model to have for any technology-centric company.