Running handin-server on Racket 6.1.1.8 fails with a contract error

[lexi-lambda]

I've been going through the Quick Start in the documentation, and running racket -l handin-server on Racket 6.1.1.8 produces the following error:

[-|2015-02-28T00:39:04] serve: contract violation;
[-|2015-02-28T00:39:04]  unit must export signature dispatch-server-tcp^
[-|2015-02-28T00:39:04]   in: the #:tcp@ argument of
[-|2015-02-28T00:39:04]       (->*
[-|2015-02-28T00:39:04]        (#:dispatch (-> connection? request? void))
[-|2015-02-28T00:39:04]        (#:confirmation-channel
[-|2015-02-28T00:39:04]         (or/c #f async-channel?)
[-|2015-02-28T00:39:04]         #:connection-close?
[-|2015-02-28T00:39:04]         boolean?
[-|2015-02-28T00:39:04]         #:initial-connection-timeout
[-|2015-02-28T00:39:04]         number?
[-|2015-02-28T00:39:04]         #:listen-ip
[-|2015-02-28T00:39:04]         (or/c #f string?)
[-|2015-02-28T00:39:04]         #:max-waiting
[-|2015-02-28T00:39:04]         exact-nonnegative-integer?
[-|2015-02-28T00:39:04]         #:port
[-|2015-02-28T00:39:04]         (between/c 0 65535)
[-|2015-02-28T00:39:04]         #:tcp@
[-|2015-02-28T00:39:04]         (unit/c
[-|2015-02-28T00:39:04]          (import)
[-|2015-02-28T00:39:04]          (export (dispatch-server-tcp^))))
[-|2015-02-28T00:39:04]        (-> void))
[-|2015-02-28T00:39:04]   contract from:
[-|2015-02-28T00:39:04]       <pkgs>/web-server-lib/web-server/web-server.rkt
[-|2015-02-28T00:39:04]   blaming: <pkgs>/handin/handin-server/run-servlet.rkt
[-|2015-02-28T00:39:04]    (assuming the contract is correct)
[-|2015-02-28T00:39:04]   at: <pkgs>/web-server-lib/web-server/web-server.rkt:16.2

It works fine using Racket 6.1.1.

[mflatt]

I've discussed this problem with @jeapostrophe . I think he's been too busy to restore the API that the handin server depends on (while keeping the new repairs), but one of us will get to it soon.

Thanks for the report!