You can find a rather extensive list here, with maybe Castl the closest to JS?

Contains moonscript and other usual suspects but also more esoteric ones like haskell, go cross compilers.

reddit permalink

Personal Photo Management powered by Go and Google TensorFlow - photoprism/photoprism

Exhaustive list, with pros and cons, of access to nextcloud files.

Includes a little 'push' function to send stuff directly to your nextcloud folders which could be adapted to different use cases.

Not mentioned: S3 primary storage on Nextcloud