diff --git a/modules/nextflow/src/main/groovy/nextflow/trace/GraphObserver.groovy b/modules/nextflow/src/main/groovy/nextflow/trace/GraphObserver.groovy
index 9fc99f8f3d..aa109d8ce8 100644
--- a/modules/nextflow/src/main/groovy/nextflow/trace/GraphObserver.groovy
+++ b/modules/nextflow/src/main/groovy/nextflow/trace/GraphObserver.groovy
@@ -16,6 +16,7 @@
 
 package nextflow.trace
 
+import java.nio.file.Files
 import java.nio.file.Path
 
 import groovy.transform.PackageScope
@@ -81,6 +82,10 @@ class GraphObserver implements TraceObserver {
     void onFlowComplete() {
         // -- normalise the DAG
         dag.normalize()
+
+        // -- make sure parent path exists
+        file.parent?.mkdirs()
+
         // -- render it to a file
         createRender().renderDocument(dag,file)
     }