diff --git a/nextnumber b/nextnumber
index 6b91a92..0c9c7b1 100755
--- a/nextnumber
+++ b/nextnumber
@@ -8,6 +8,6 @@ fi
 
 for i in 1 2
 do
-  last=$(grep -hv "^prop" ./**/*.hs | grep -Ewo "$i[0-9]{3}" | sort -n | tail -n 1)
+  last=$(grep -hv "^prop" ./**/*.hs | grep -Ewo "${i}[0-9]{3}" | sort -n | tail -n 1)
   echo "Next ${i}xxx: $((last+1))"
 done
diff --git a/test/check_release b/test/check_release
index 5e73d9e..b9cd34b 100755
--- a/test/check_release
+++ b/test/check_release
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+# shellcheck disable=SC2257
 
 failed=0
 fail() {