Can't run editor due to Racket error

[tekknolagi]

When starting up, I get:

maple% racket src/fructure.rkt 
shared/slash-patterns/slash-patterns.rkt:77:34: ~@: unbound identifier in module
  in: ~@

I'm not so familiar with Racket so I've no idea what this means.

I am running Ubuntu:

maple% lsb_release -irc
Distributor ID:	Ubuntu
Release:	18.04
Codename:	bionic

Racket version:

maple% racket --version
Welcome to Racket v6.11.