Actually, I would deprioritize c extension support. The jruby ecosystem is extremely mature and production ready. For example, database connectors exist which

Actually, I would deprioritize c extension support. The jruby ecosystem is extremely mature and production ready. For example, database connectors exist which are pure java rather than based on c extensions. They may be better as well. Same goes for ssl (https://github.com/jruby/jruby-openssl/blob/master/README.md https://github.com/jruby/jruby-openssl/blob/master/README.md) and xml parsing (https://github.com/YorickPeterse/oga/blob/master/README.md https://github.com/YorickPeterse/oga/blob/master/README.md) Also goes for all the json parsing, etc stuff which seems to need c extensions. Lots of systems stuff is perfectly workable using jruby (https://github.com/minimagick/minimagick/blob/master/README.md https://github.com/minimagick/minimagick/blob/master/README....) This would be a different story if you were doing jython fof example - python does not have a viable java based ecosystem. If I were you, i would NOT focus on c extensions and instead work on other stuff (like startup speed)