diff --git a/CHANGES.md b/CHANGES.md
index 5b5f69b..5f9b83f 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -2,6 +2,8 @@
 
 * Allow HTTP URLs and other fsspec-supported specifiers as notebook and
   environment file paths (#42)
+* Add `s:version` metadata field to CWL as a synonym for
+  `s:softwareVersion` (#90)
 
 ## Changes in 0.1.2
 
diff --git a/xcengine/core.py b/xcengine/core.py
index 5cbd315..a2b3edc 100644
--- a/xcengine/core.py
+++ b/xcengine/core.py
@@ -124,6 +124,7 @@ def create_cwl(self, image_tag: str) -> dict[str, Any]:
         return {
             "cwlVersion": "v1.0",
             "$namespaces": {"s": "https://schema.org/"},
+            "s:version": "1.0.0",
             "s:softwareVersion": "1.0.0",
             "schemas": [
                 "http://schema.org/version/9.0/schemaorg-current-http.rdf"