diff --git a/pkgs/racket-test/tests/pkg/tests-locking.rkt b/pkgs/racket-test/tests/pkg/tests-locking.rkt
index 768b0ce615..a3bcf6ea54 100644
--- a/pkgs/racket-test/tests/pkg/tests-locking.rkt
+++ b/pkgs/racket-test/tests/pkg/tests-locking.rkt
@@ -14,38 +14,41 @@
 
    ;; Step 1: Start a special server that waits for our signal to respond
    (initialize-catalogs)
-   (define okay-to-start?-sema (make-semaphore))
-   (define okay-to-respond?-sema (make-semaphore))
-   (define okay-to-quit?-sema (make-semaphore))
+
+   (define succeed-catalog (make-channel))
+   (define fail-catalog (make-channel))
+
    (thread
     (λ ()
       (serve/servlet (pkg-index/basic
                       (λ (pkg-name)
-                        (semaphore-post okay-to-start?-sema)
-                        (semaphore-wait okay-to-respond?-sema)
+                        (channel-put fail-catalog 'go)
+                        (sync fail-catalog) ;; => 'continue
                         (define r (hash-ref *index-ht-1* pkg-name #f))
                         r)
                       (λ () *index-ht-1*))
                      #:command-line? #t
                      #:servlet-regexp #rx""
-                     #:port 9967)
-      (semaphore-wait okay-to-quit?-sema)
-      (semaphore-wait okay-to-quit?-sema)))
+                     #:port 9967)))
 
    ;; Step 2: Assign it as our server
    $ "raco pkg config --set catalogs http://localhost:9967"
 
+   $ "raco pkg show pkg-test1"
+
    ;; Step 3: Start an installation request in the background
    (thread
     (λ ()
       (shelly-begin
-       $ "raco pkg install pkg-test1")
-      (semaphore-post okay-to-quit?-sema)))
-   (semaphore-wait okay-to-start?-sema)
+       $ "raco pkg install pkg-test1"
+       $ "raco pkg show pkg-test1")
+      (channel-put succeed-catalog 'done)))
+   (sync fail-catalog) ;; => 'go
 
    ;; Step 4: Start the installation request that will fail
    $ "raco pkg install pkg-test1" =exit> 1
 
    ;; Step 5: Free the other one
-   (semaphore-post okay-to-respond?-sema)
-   (semaphore-post okay-to-quit?-sema))))
+   (channel-put fail-catalog 'continue)
+   (sync succeed-catalog) ;; => 'done
+   )))