diff --git a/pkg/api/invocation/api.go b/pkg/api/invocation/api.go
index 38b3a1c0..d29a60ca 100644
--- a/pkg/api/invocation/api.go
+++ b/pkg/api/invocation/api.go
@@ -58,11 +58,7 @@ func (ia *Api) Cancel(invocationId string) error {
 		Timestamp: ptypes.TimestampNow(),
 		Hints:     &fes.EventHints{Completed: true},
 	}
-	err := ia.es.Append(event)
-	if err != nil {
-		return err
-	}
-	return nil
+	return ia.es.Append(event)
 }
 
 func (ia *Api) MarkCompleted(invocationId string, output *types.TypedValue) error {
diff --git a/pkg/types/aggregates/invocation.go b/pkg/types/aggregates/invocation.go
index 2a7a10a0..270c0f87 100644
--- a/pkg/types/aggregates/invocation.go
+++ b/pkg/types/aggregates/invocation.go
@@ -114,11 +114,7 @@ func (wi *WorkflowInvocation) ApplyEvent(event *fes.Event) error {
 			"event": event,
 		}).Warn("Skipping unimplemented event.")
 	}
-	if err != nil {
-		return err
-	}
-
-	return nil
+	return err
 }
 
 func (wi *WorkflowInvocation) applyTaskEvent(event *fes.Event) error {
diff --git a/pkg/types/helpers.go b/pkg/types/helpers.go
index 1c3b690d..6832ae9f 100644
--- a/pkg/types/helpers.go
+++ b/pkg/types/helpers.go
@@ -180,10 +180,8 @@ func SingleDefaultInput(t *TypedValue) map[string]*TypedValue {
 type Requires map[string]*TaskDependencyParameters
 
 func (r Requires) Add(s ...string) Requires {
-	if s != nil {
-		for _, v := range s {
-			r[v] = nil
-		}
+	for _, v := range s {
+		r[v] = nil
 	}
 	return r
 }