Systems such as auth0 are only really practical because they allow you to run the server on a different domain from the rest of the app, without having to do all kinds of tricky proxying and routing magic.
This will mean that the client will be responsible for storing the token, probably in localstorage or the like, but it will still make for a much easier integration point than forcing them to bend their backend and front-end to suit concorda.
Systems such as auth0 are only really practical because they allow you to run the server on a different domain from the rest of the app, without having to do all kinds of tricky proxying and routing magic.
This will mean that the client will be responsible for storing the token, probably in localstorage or the like, but it will still make for a much easier integration point than forcing them to bend their backend and front-end to suit concorda.