diff --git a/metropolis/pkg/supervisor/supervisor_test.go b/metropolis/pkg/supervisor/supervisor_test.go
index db84163..cf303e8 100644
--- a/metropolis/pkg/supervisor/supervisor_test.go
+++ b/metropolis/pkg/supervisor/supervisor_test.go
@@ -23,6 +23,34 @@
 	"time"
 )
 
+// waitSettle waits until the supervisor reaches a 'settled' state - ie., one
+// where no actions have been performed for a number of GC cycles.
+// This is used in tests only.
+func (s *supervisor) waitSettle(ctx context.Context) error {
+	waiter := make(chan struct{})
+	s.pReq <- &processorRequest{
+		waitSettled: &processorRequestWaitSettled{
+			waiter: waiter,
+		},
+	}
+
+	select {
+	case <-ctx.Done():
+		return ctx.Err()
+	case <-waiter:
+		return nil
+	}
+}
+
+// waitSettleError wraps waitSettle to fail a test if an error occurs, eg. the
+// context is canceled.
+func (s *supervisor) waitSettleError(ctx context.Context, t *testing.T) {
+	err := s.waitSettle(ctx)
+	if err != nil {
+		t.Fatalf("waitSettle: %v", err)
+	}
+}
+
 func runnableBecomesHealthy(healthy, done chan struct{}) Runnable {
 	return func(ctx context.Context) error {
 		Signal(ctx, SignalHealthy)
diff --git a/metropolis/pkg/supervisor/supervisor_testhelpers.go b/metropolis/pkg/supervisor/supervisor_testhelpers.go
index 771e02f..5431ea1 100644
--- a/metropolis/pkg/supervisor/supervisor_testhelpers.go
+++ b/metropolis/pkg/supervisor/supervisor_testhelpers.go
@@ -15,36 +15,3 @@
 // limitations under the License.
 
 package supervisor
-
-import (
-	"context"
-	"testing"
-)
-
-// waitSettle waits until the supervisor reaches a 'settled' state - ie., one
-// where no actions have been performed for a number of GC cycles.
-// This is used in tests only.
-func (s *supervisor) waitSettle(ctx context.Context) error {
-	waiter := make(chan struct{})
-	s.pReq <- &processorRequest{
-		waitSettled: &processorRequestWaitSettled{
-			waiter: waiter,
-		},
-	}
-
-	select {
-	case <-ctx.Done():
-		return ctx.Err()
-	case <-waiter:
-		return nil
-	}
-}
-
-// waitSettleError wraps waitSettle to fail a test if an error occurs, eg. the
-// context is canceled.
-func (s *supervisor) waitSettleError(ctx context.Context, t *testing.T) {
-	err := s.waitSettle(ctx)
-	if err != nil {
-		t.Fatalf("waitSettle: %v", err)
-	}
-}