diff --git a/steps/blsmooth.cwl b/steps/blsmooth.cwl
index 449e392b2181106bbe988f441406d8787d20438e..f1cbe6dc366f9bf388f54d48dafd276e4a8679d9 100644
--- a/steps/blsmooth.cwl
+++ b/steps/blsmooth.cwl
@@ -76,12 +76,12 @@ outputs:
     type: Directory
     outputBinding:
       glob: $(inputs.msin.basename)
-
+hints:
+ - class: DockerRequirement
+   dockerPull: 'prefactor:latest'
 requirements:
-- class: DockerRequirement
-  dockerPull: 'prefactor:latest'
-- class: InitialWorkDirRequirement
+ - class: InitialWorkDirRequirement
   listing:
     - entry: $(inputs.msin)
       writable: true
-- class: InlineJavascriptRequirement
+ - class: InlineJavascriptRequirement