diff --git a/metropolis/pkg/supervisor/supervisor_node.go b/metropolis/pkg/supervisor/supervisor_node.go
index 4fb2ddb..76d656c 100644
--- a/metropolis/pkg/supervisor/supervisor_node.go
+++ b/metropolis/pkg/supervisor/supervisor_node.go
@@ -242,7 +242,7 @@
 	}
 
 	// Check the requested runnable names.
-	for name, _ := range runnables {
+	for name := range runnables {
 		if !reNodeName.MatchString(name) {
 			return fmt.Errorf("runnable name %q is invalid", name)
 		}
@@ -272,7 +272,7 @@
 
 	// Schedule execution of group members.
 	go func() {
-		for name, _ := range runnables {
+		for name := range runnables {
 			n.sup.pReq <- &processorRequest{
 				schedule: &processorRequestSchedule{
 					dn: dns[name],
diff --git a/metropolis/pkg/supervisor/supervisor_processor.go b/metropolis/pkg/supervisor/supervisor_processor.go
index 8b5b336..816298d 100644
--- a/metropolis/pkg/supervisor/supervisor_processor.go
+++ b/metropolis/pkg/supervisor/supervisor_processor.go
@@ -309,7 +309,7 @@
 
 	// Cancel all siblings.
 	if n.parent != nil {
-		for name, _ := range n.parent.groupSiblings(n.name) {
+		for name := range n.parent.groupSiblings(n.name) {
 			if name == n.name {
 				continue
 			}
@@ -374,7 +374,7 @@
 
 	// We build a queue of nodes to visit, starting from the leaves.
 	queue = []*node{}
-	for l, _ := range leaves {
+	for l := range leaves {
 		queue = append(queue, s.nodeByDN(l))
 	}
 
@@ -493,7 +493,7 @@
 	}
 
 	// Reinitialize and reschedule all subtrees
-	for dn, _ := range can {
+	for dn := range can {
 		n := s.nodeByDN(dn)
 
 		// Only back off when the node unexpectedly died - not when it got