I won’t comment on the relative numbers because there are top-notch developers in many language communities. I think the more important point is that Julia has

I won’t comment on the relative numbers because there are top-notch developers in many language communities. I think the more important point is that Julia has attracted enough first-rate people to self-sustainably build out an ecosystem — and even more keep joining. Several aspects of Julia’s design and core tooling interact to provide compounding leverage to this group. I think it’s a similar situation to the development of the NumPy ecosystem where standardizing on a common array data structure and API led to an explosion of interoperable libraries. Julia arguably takes that a step further by allowing any code to interoperate with high performance and fluent APIs. Julia’s performance characteristics also reduce the barrier to entry because people can make deep contributions throughout the ecosystem without needing to develop low-level programming expertise on top of their domain-specific knowledge.