diff --git a/src/Squot.package/SquotCypressCodeSerializer.class/instance/writeDiff..st b/src/Squot.package/SquotCypressCodeSerializer.class/instance/writeDiff..st
index de351b7a7..04c0502bf 100644
--- a/src/Squot.package/SquotCypressCodeSerializer.class/instance/writeDiff..st
+++ b/src/Squot.package/SquotCypressCodeSerializer.class/instance/writeDiff..st
@@ -53,8 +53,9 @@ writeDiff: aSquotArtifactDiff
 				[classTrait := classTraits at: each className.
 				(newDefinitions includes: classTrait) ifFalse: [missingClassTraits add: classTrait]]].
 	(missingClassifiers select: [:each | each isTraitDefinition])
-		do: [:each | | classTrait | classTrait := classTraits at: each className.
-			(newDefinitions includes: classTrait) ifFalse: [missingClassTraits add: classTrait]].
+		do: [:each | | classTrait | classTrait := classTraits at: each className ifAbsent: [].
+			(classTrait notNil and: [(newDefinitions includes: classTrait) not])
+				ifTrue: [missingClassTraits add: classTrait]].
 	cypressWriter writeDefinitions: newDefinitions, missingClassifiers, missingClassTraits.
 	"Fix up methodProperties.json files (they now only include the methods that were newly written)."
 	allMethods := (newDefinitions select: [:each | each isMethodDefinition]) collect: [:each | each description -> each] as: Dictionary.
diff --git a/src/Squot.package/SquotCypressCodeSerializer.class/methodProperties.json b/src/Squot.package/SquotCypressCodeSerializer.class/methodProperties.json
index b15526245..03350bdba 100644
--- a/src/Squot.package/SquotCypressCodeSerializer.class/methodProperties.json
+++ b/src/Squot.package/SquotCypressCodeSerializer.class/methodProperties.json
@@ -22,7 +22,7 @@
 		"write:" : "jr 5/9/2017 18:24",
 		"writeClass:" : "jr 9/3/2020 22:48",
 		"writeDefinitions:" : "jr 1/29/2017 21:08",
-		"writeDiff:" : "jr 8/7/2022 23:33",
+		"writeDiff:" : "jr 8/8/2022 19:29",
 		"writeMCSnapshot:forPackageNamed:from:" : "jr 3/16/2019 23:35",
 		"writePackage:" : "jr 9/3/2020 22:47",
 		"writePropertiesIfExists" : "jr 9/3/2020 22:47" } }