Ruby 3 support or alternative

[knugie]

Is there a (suggested) way to use net-ssh-gateway with Ruby 3.0.0?
Gemfile:

#...
gem 'net-ssh-gateway'
#...

Lib code:

# ...
require 'net/ssh/gateway'
# ...

Execution:

/path/to/lib/file.rb:3:in `require': cannot load such file -- net/ssh/gateway (LoadError)

There are no issues running bundle install and everything works with Ruby 2.7.0.

Thanks a lot.