How do I get `jbuild runtest -p redis-async` to work?

jbuild

(jbuild_version 1)

(library
 ((name redis_test)
  (modules test)
  (wrapped false)
  (libraries (redis oUnit))))

(executable
  ((name test_sync)
   (libraries (redis_test redis_sync))
   (modules (test_sync))))

(executable
  ((name test_lwt)
   (libraries (redis_test redis_lwt))
   (modules (test_lwt))))

(executable
  ((name test_async)
   (libraries (redis_test redis_async))
   (modules (test_async))))

(alias
 ((name runtest)
  (deps (test_lwt.exe))
  (package redis-lwt)
  (action (run ${<}))))

(alias
 ((name runtest)
  (deps (test_async.exe))
  (package redis-async)
  (action (run ${<}))))

(alias
 ((name   runtest)
  (deps   (test_sync.exe))
  (package redis-sync)
  (action (run ${<}))))