It is compatible, you just have to configure the other client to use the same servers.

For example, to use the "wormhole" Python CLI with Destiny, you can do this:

wormhole --relay-url wss://mailbox.mw.leastauthority.com/v1 --transit-helper tcp:relay.mw.leastauthority.com:4001 send README.rst

Then, the code it prints out can be consumed by a Destiny (or https://winden.app ) client.