Concurrent, preemptive socket servers with robust failure handling are "trivial" in Erlang. I'd say 10x productivity would be an understatement compared to othe

Concurrent, preemptive socket servers with robust failure handling are "trivial" in Erlang. I'd say 10x productivity would be an understatement compared to other languages. Writing FPU code? 0.1x productivity would be generous. It depends on the problem you're solving. Obviously we're throwing around random values like 5x and 10x "productivity" but it's more nuanced than that. There's more than LoC that can be measured as "productivity": how about bug count and severity per LoC written, refactoring cost, performance, robustness, library support, setup time, etc. And many more metrics. Metrics are valued differently depending on the programmer and the problem. Eg, who cares if my CRUD web app has memory leaks and crashes randomly, it's stateless! There's not one really great language because every programmer their own productivity priorities. Often, though, LoC is used as a poor proxy for this multi-dimensional "productivity" value.