diff --git a/abaplint.json b/abaplint.json
index 75b830f51..f66547c59 100644
--- a/abaplint.json
+++ b/abaplint.json
@@ -59,6 +59,13 @@
     "breakpoint": {
       "enabled": true
     },
+    "nesting": {
+      "enabled": true,
+      "depth": 5
+    },
+    "keywords_upper": {
+      "enabled": true
+    },
     "cloud_types": {
       "enabled": true
     },
@@ -97,4 +104,3 @@
     }
   }
 }
-  
diff --git a/package.json b/package.json
index 9661a3c49..9951b11ea 100644
--- a/package.json
+++ b/package.json
@@ -11,6 +11,6 @@
   },
   "devDependencies": {
     "abapmerge": "^0.11.0",
-    "abaplint": "^1.3.5"
+    "abaplint": "^1.4.0"
   }
 }
diff --git a/src/zcl_abapgit_zip.clas.abap b/src/zcl_abapgit_zip.clas.abap
index 3579335b9..ed7bd27a7 100644
--- a/src/zcl_abapgit_zip.clas.abap
+++ b/src/zcl_abapgit_zip.clas.abap
@@ -504,7 +504,7 @@ CLASS ZCL_ABAPGIT_ZIP IMPLEMENTATION.
 
     ENDLOOP.
 
-    DELETE rt_files WHERE filename is initial.
+    DELETE rt_files WHERE filename IS INITIAL.
 
     normalize_path( CHANGING ct_files = rt_files ).