diff --git a/src/main/java/org/jastadd/relast/plugin/RelastTest.java b/src/main/java/org/jastadd/relast/plugin/RelastTest.java
index e7172ac8c67170977ddadcd2a44930b9561993db..3927564e03f788fb832a0ed4c639661040ae644f 100644
--- a/src/main/java/org/jastadd/relast/plugin/RelastTest.java
+++ b/src/main/java/org/jastadd/relast/plugin/RelastTest.java
@@ -49,6 +49,7 @@ public class RelastTest extends DefaultTask {
     this.compilerLocation = compilerLocation;
   }
 
+  @Optional
   @Input
   public boolean isVerbose() {
     return verbose;
@@ -108,6 +109,7 @@ public class RelastTest extends DefaultTask {
     this.grammarName = grammarName;
   }
 
+  @Optional
   @Input
   public String getListClass() {
     return listClass;
@@ -117,6 +119,7 @@ public class RelastTest extends DefaultTask {
     this.listClass = listClass;
   }
 
+  @Optional
   @Input
   public String getJastAddList() {
     return jastAddList;
@@ -126,6 +129,7 @@ public class RelastTest extends DefaultTask {
     this.jastAddList = jastAddList;
   }
 
+  @Optional
   @Input
   public String getSerializer() {
     return serializer;
@@ -145,8 +149,8 @@ public class RelastTest extends DefaultTask {
     this.runJastAdd = runJastAdd;
   }
 
-  @Input
   @Optional
+  @Input
   public String getOutputDir() {
     return outputDir;
   }
@@ -164,6 +168,7 @@ public class RelastTest extends DefaultTask {
     this.packageName = packageName;
   }
 
+  @Optional
   @Input
   public List<String> getExtraJastAddOptions() {
     return extraJastAddOptions;
@@ -177,6 +182,7 @@ public class RelastTest extends DefaultTask {
     this.extraJastAddOptions.addAll(Arrays.asList(fileArray));
   }
 
+  @Optional
   @Input
   public List<String> getMoreInputFiles() {
     return moreInputFiles;