@mariusormarius Mastodon supports all standard activities and has a wide variety of clients. I don't find softwares with similar capabilities impressive, although I respect your work (the only ActivityPub server-client project that is not a vaporware).
I doubt that language choice makes much difference, and Rust is not a dynamically typed language anyway. The difficulty you might be facing is likely due to JSON-LD.
The thanks was for your input with regards to collection management.