> I've actually come to think that the best languages are general-purpose languages and you should just use one language (Scala) for everything. I disagree ver

> I've actually come to think that the best languages are general-purpose languages and you should just use one language (Scala) for everything. I disagree very strongly with this. My original background is in scientific programming, which I learned primarily during my PhD. Since then I've been working in, and now leading, teams comprised of both data scientists (principally from a scientific or mathematics background) and data engineers (primarily from a software engineering background). I can tell you from experience that trying to do everything in one language works extremely poorly in practice. Scala is a great example. People who focus primarily on scaling out relatively simple data processing systems, perhaps with some machine learning thrown in, are big fans of scala. Any scientific programmer that I know (note that machine learning, the most popular kind of scientific programming on HN, is only one very tiny part of the field), including the data scientists in my team, simply cannot do their jobs with scala. The typical patterns scala encourages are fundamentally unsuited to advanced scientific programming, which is why almost nobody in academic science uses scala [insert obligatory indignation about the wonders of functional programming here]. The number of scientific libraries available for scala is absolutely dwarfed by the C++/Python ecosystem. Note that I'm not saying that scala is a bad language; I'm saying that every language has advantages and disadvantages for different kinds of work, and different mindsets. I won't presume to accuse you of this, because I don't know your position, but this kind of viewpoint is typically held by the kind of programmer who dramatically underestimates the complexity of scientific programming.