Press Start has gotten the day one Nintendo Switch patch that adds online functionality and has confirmed that Friend Codes are part of the online infastructure.

As well as being able to add local users and users you've played with (including on Miitomo and Super Mario Run), you will be able to add friends using Friend Codes, a feature that has long been criticised as being outdated in modern online gaming.

The friend codes are 12 digits and available within your personal profile page (prefixed with SW-).

While a lot of online questions remain, at least one has been cleared up for now.  Better start learning your Friend Code!