Service programming, as in not-web-programming. Solr, for a random example, would not be a good task for either Python or Javascript, there are tricky concurre

Service programming, as in not-web-programming. Solr, for a random example, would not be a good task for either Python or Javascript, there are tricky concurrency concerns involving your index reads/writes and they're both just-plain-not-fast-enough. The only dynamic language I know of that isn't just embarrassingly slow compared to Java is Lua, due to some extreme fanciness on the part of their VM.