diff --git a/sendmail/cmd/cmd.go b/sendmail/cmd/cmd.go
index 2672a29..2c8f723 100644
--- a/sendmail/cmd/cmd.go
+++ b/sendmail/cmd/cmd.go
@@ -125,7 +125,7 @@ func Run() {
 
 	msg, err := mail.ReadMessage(bytes.NewReader(body))
 	if err != nil {
-		fmt.Fprintln(os.Stderr, fmt.Sprintf("error parsing message body: %s", err))
+		fmt.Fprintf(os.Stderr, "error parsing message body: %si\n", err)
 		os.Exit(11)
 	}
 
diff --git a/storage/database_test.go b/storage/database_test.go
index e9876ee..0612f1b 100644
--- a/storage/database_test.go
+++ b/storage/database_test.go
@@ -263,10 +263,10 @@ func assertEqual(t *testing.T, a interface{}, b interface{}, message string) {
 func assertEqualStats(t *testing.T, total int, unread int) {
 	s := StatsGet()
 	if total != s.Total {
-		t.Fatal(fmt.Sprintf("Incorrect total mailbox stats: \"%d\" != \"%d\"", total, s.Total))
+		t.Fatalf("Incorrect total mailbox stats: \"%d\" != \"%d\"", total, s.Total)
 	}
 
 	if unread != s.Unread {
-		t.Fatal(fmt.Sprintf("Incorrect unread mailbox stats: \"%d\" != \"%d\"", unread, s.Unread))
+		t.Fatalf("Incorrect unread mailbox stats: \"%d\" != \"%d\"", unread, s.Unread)
 	}
 }