diff --git a/nb-virtdata/virtdata-lang/src/main/java/io/nosqlbench/virtdata/lang/grammars/VirtData.g4 b/nb-virtdata/virtdata-lang/src/main/java/io/nosqlbench/virtdata/lang/grammars/VirtData.g4
index 74b1f17fc..7220721c1 100644
--- a/nb-virtdata/virtdata-lang/src/main/java/io/nosqlbench/virtdata/lang/grammars/VirtData.g4
+++ b/nb-virtdata/virtdata-lang/src/main/java/io/nosqlbench/virtdata/lang/grammars/VirtData.g4
@@ -3,7 +3,7 @@ grammar VirtData;
 
 virtdataRecipe : virtdataFlow (specend virtdataFlow?)* EOF ;
 
-virtdataFlow : (COMPOSE)? expression (';' expression?)* ;
+virtdataFlow : (COMPOSE)? expression (';' expression? | WS? expression)* ;
 
 expression : (lvalue ASSIGN)? virtdataCall ;
 
diff --git a/nb-virtdata/virtdata-lang/src/main/java/io/nosqlbench/virtdata/lang/parser/VirtDataDSL.java b/nb-virtdata/virtdata-lang/src/main/java/io/nosqlbench/virtdata/lang/parser/VirtDataDSL.java
index 8a7f21dc7..3ea625e95 100644
--- a/nb-virtdata/virtdata-lang/src/main/java/io/nosqlbench/virtdata/lang/parser/VirtDataDSL.java
+++ b/nb-virtdata/virtdata-lang/src/main/java/io/nosqlbench/virtdata/lang/parser/VirtDataDSL.java
@@ -20,9 +20,7 @@ import io.nosqlbench.virtdata.lang.ast.VirtDataAST;
 import io.nosqlbench.virtdata.lang.ast.VirtDataFlow;
 import io.nosqlbench.virtdata.lang.generated.VirtDataLexer;
 import io.nosqlbench.virtdata.lang.generated.VirtDataParser;
-import org.antlr.v4.runtime.CharStreams;
-import org.antlr.v4.runtime.CodePointCharStream;
-import org.antlr.v4.runtime.CommonTokenStream;
+import org.antlr.v4.runtime.*;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
@@ -36,14 +34,11 @@ public class VirtDataDSL {
 
         try {
             CodePointCharStream cstream = CharStreams.fromString(input);
-            VirtDataLexer lexer = new VirtDataLexer(cstream);
-            CommonTokenStream tokens = new CommonTokenStream(lexer);
-            VirtDataParser parser = new VirtDataParser(tokens);
+            VirtDataParser parser = getVirtDataParser(cstream);
             VirtDataBuilder astListener = new VirtDataBuilder();
             parser.addParseListener(astListener);
-
-            VirtDataParser.VirtdataFlowContext virtdataFlowContext = parser.virtdataFlow();
-            logger.trace(() -> "parse tree: " + virtdataFlowContext.toStringTree(parser));
+            VirtDataParser.VirtdataRecipeContext virtdataRecipeContext = parser.virtdataRecipe();
+            logger.trace(() -> "parse tree: " + virtdataRecipeContext.toStringTree(parser));
 
             if (astListener.hasErrors()) {
                 System.out.println(astListener.getErrorNodes());
@@ -67,6 +62,18 @@ public class VirtDataDSL {
         }
     }
 
+    private static VirtDataParser getVirtDataParser(CodePointCharStream cstream) {
+        VirtDataLexer lexer = new VirtDataLexer(cstream);
+        lexer.addErrorListener(new BaseErrorListener() {
+            @Override
+            public void syntaxError(Recognizer<?, ?> recognizer, Object offendingSymbol, int line, int charPositionInLine, String msg, RecognitionException e) {
+                throw new RuntimeException(e);
+            }
+        });
+        CommonTokenStream tokens = new CommonTokenStream(lexer);
+        return new VirtDataParser(tokens);
+    }
+
     public static class ParseResult {
         public Throwable throwable;
         public VirtDataFlow flow;