It's a parallel world in which developers either use pure Ruby gems or Java jars. For example, the database drivers are JDBC adapters straight from the Java world not the usual mysql2 or pg gems. Obviously the programs that use them are not portable unless there is a compatibility layer. In that example, ActiveRecord abstracts the drivers.
I don't know anything about Rust but maybe it could end up in the same way.
It's a parallel world in which developers either use pure Ruby gems or Java jars. For example, the database drivers are JDBC adapters straight from the Java world not the usual mysql2 or pg gems. Obviously the programs that use them are not portable unless there is a compatibility layer. In that example, ActiveRecord abstracts the drivers.
I don't know anything about Rust but maybe it could end up in the same way.