diff --git a/functional-tests/functional-tests.scm b/functional-tests/functional-tests.scm
index 5e04c2e..8b15509 100644
--- a/functional-tests/functional-tests.scm
+++ b/functional-tests/functional-tests.scm
@@ -222,6 +222,7 @@
               (thunk)
               #t)))))
 
+  ;; Returns #t if all tests pass.
   (define (run-scenarios ss)
     (let ((pass 0)
           (fail 0)
@@ -250,7 +251,8 @@
                        (cat (dsp ", ")
                             (num fail)
                             (dsp " failures.")))
-                   nl))))
+                   nl))
+      (zero? fail)))
 
   ;;-----------------------------------------------
 
diff --git a/functional-tests/run-functional-tests.scm b/functional-tests/run-functional-tests.scm
index 0306034..016e065 100644
--- a/functional-tests/run-functional-tests.scm
+++ b/functional-tests/run-functional-tests.scm
@@ -5,5 +5,8 @@
 
 (register-thin-tests)
 (register-cache-tests)
-(run-scenarios (list-scenarios))
+
+(if (run-scenarios (list-scenarios))
+    (exit)
+    (exit #f))