diff --git a/star.wdl b/star.wdl
index 8b9f435b705c89ec10c80f15c611fb6abe7a2338..46d401c178ccfcfc8c6bec5ff574b0d88ec3e96c 100644
--- a/star.wdl
+++ b/star.wdl
@@ -13,7 +13,7 @@ task Star {
     String? twopassMode
     Array[String]? outSAMattrRGline
 
-    Float? memory
+    Int? memory
 
     #TODO needs to be extended for all possible output extensions
     Map[String, String] samOutputNames = {"BAM SortedByCoordinate": "sortedByCoord.out.bam"}
diff --git a/stringtie.wdl b/stringtie.wdl
index a938b147acbae2525f28b36a7979fffd254df8eb..6031d7966ede0e19ef3e90a3edb8116767cb20cc 100644
--- a/stringtie.wdl
+++ b/stringtie.wdl
@@ -28,6 +28,6 @@ task Stringtie {
     }
 
     runtime {
-        threads: select_first([threads])
+        threads: select_first([threads, 1])
     }
 }
\ No newline at end of file