diff --git a/Iceberg-Plugin-Migration/IceConvertFormatAction.class.st b/Iceberg-Plugin-Migration/IceConvertFormatAction.class.st
index 554caf39f1..b7f0770e95 100644
--- a/Iceberg-Plugin-Migration/IceConvertFormatAction.class.st
+++ b/Iceberg-Plugin-Migration/IceConvertFormatAction.class.st
@@ -34,21 +34,9 @@ IceConvertFormatAction >> codeDirectoryWithDelim [
 
 { #category : #private }
 IceConvertFormatAction >> ensureMCClassOrganisationHasCorrectStructure: mcVersion [
- 	| organisation |
 
-   	organisation := mcVersion snapshot definitions 
- 		detect: [ :each | each isOrganizationDefinition ].
-
-   	(organisation categories size = 1) ifFalse: [ | baseCategory |
- 		baseCategory := self 
- 			obtainCommonCategory: organisation categories first 
- 			from: organisation categories.
- 		baseCategory ifEmpty: [ 
- 			self error: 'I didn''t find a base category, something is wrong with the package definition' ].
- 		baseCategory = organisation categories first ifFalse: [ 
- 			organisation categories: (organisation categories copyWithFirst: baseCategory) ] ].
-
-   	^ mcVersion  
+	(mcVersion snapshot definitions detect: [ :each | each isOrganizationDefinition ]) packageName ifNil: [
+		self error: 'I have no package name in the organization definition' ]
 ]
 
 { #category : #private }
@@ -57,16 +45,14 @@ IceConvertFormatAction >> ensureMCVersionWithClassOrganisation: mcVersion [
 	 only for extensions, we need to ensure it has one, otherwise package creation will 
 	 fail"
 
-	^ mcVersion snapshot definitions 
-		detect: [ :each | each isClassDefinition ]
-		ifFound: [ :each | mcVersion ]
-		ifNone: [ 
-			MCVersion 
-				package: mcVersion package
-				info: mcVersion info
-				snapshot: (MCSnapshot fromDefinitions: (
-					{ MCOrganizationDefinition categories: { mcVersion package name }}, 
-					mcVersion snapshot definitions)) ]
+	^ mcVersion snapshot definitions
+		  detect: [ :each | each isClassDefinition ]
+		  ifFound: [ :each | mcVersion ]
+		  ifNone: [
+			  MCVersion
+				  package: mcVersion package
+				  info: mcVersion info
+				  snapshot: (MCSnapshot fromDefinitions: { (MCOrganizationDefinition packageName: mcVersion package name) } , mcVersion snapshot definitions) ]
 ]
 
 { #category : #execution }
@@ -103,22 +89,20 @@ IceConvertFormatAction >> mergeWithCurrentBranch: anObject [
 
 { #category : #private }
 IceConvertFormatAction >> migratePackage: packageName commit: commit [
+
 	| filetreePackage srcDir subDirWithDelim mcVersion |
-	
 	srcDir := self codeDirectory.
 	subDirWithDelim := self codeDirectoryWithDelim.
-	
+
 	mcVersion := (commit versionFor: packageName) mcVersion.
 	mcVersion := self ensureMCVersionWithClassOrganisation: mcVersion.
-	mcVersion := self ensureMCClassOrganisationHasCorrectStructure: mcVersion.
-	self writerClass 
-		forInternalStoreFileOut: mcVersion 
-		on: repository.
+	self ensureMCClassOrganisationHasCorrectStructure: mcVersion.
+	self writerClass forInternalStoreFileOut: mcVersion on: repository.
 	filetreePackage := commit writerClass directoryNameFor: packageName.
 	(srcDir / filetreePackage) ensureDeleteAll.
-	self repository addFilesToIndex: { 
-		subDirWithDelim, (IceLibgitTonelWriter directoryNameFor: packageName).
-		subDirWithDelim, (IceLibgitFiletreeWriter directoryNameFor: packageName) }
+	self repository addFilesToIndex: {
+			(subDirWithDelim , (IceLibgitTonelWriter directoryNameFor: packageName)).
+			(subDirWithDelim , (IceLibgitFiletreeWriter directoryNameFor: packageName)) }
 ]
 
 { #category : #private }
@@ -152,17 +136,6 @@ IceConvertFormatAction >> migrateSources [
 		andParents: { commit }.
 ]
 
-{ #category : #private }
-IceConvertFormatAction >> obtainCommonCategory: aString from: aCollection [
-
-   	^ (aCollection allSatisfy: [ :each | each beginsWith: aString ])
- 		ifTrue: [ aString ]
- 		ifFalse: [ 
- 			(aString includes: $-) 
- 				ifTrue: [ self obtainCommonCategory: (aString copyUpToLast: $-) from: aCollection ]
- 				ifFalse: [ '' ] ] 
-]
-
 { #category : #private }
 IceConvertFormatAction >> removeFiletreeRemnants [
 	"remove .filetree remaining"
diff --git a/Iceberg/IceMCDefinitionImporter.class.st b/Iceberg/IceMCDefinitionImporter.class.st
index d76421608b..1aea3ee983 100644
--- a/Iceberg/IceMCDefinitionImporter.class.st
+++ b/Iceberg/IceMCDefinitionImporter.class.st
@@ -123,9 +123,11 @@ IceMCDefinitionImporter >> visitMethodDefinition: aMCMethodDefinition [
 ]
 
 { #category : #visiting }
-IceMCDefinitionImporter >> visitOrganizationDefinition: aMCOrganizationDefinition [ 
-	
-	packageNode value categories: aMCOrganizationDefinition categories
+IceMCDefinitionImporter >> visitOrganizationDefinition: aMCOrganizationDefinition [
+
+	packageNode value
+		packageName: aMCOrganizationDefinition packageName;
+		tagNames: aMCOrganizationDefinition tagNames
 ]
 
 { #category : #visiting }
diff --git a/Iceberg/IcePackageDefinition.class.st b/Iceberg/IcePackageDefinition.class.st
index 771ac28641..a1392a0d5d 100644
--- a/Iceberg/IcePackageDefinition.class.st
+++ b/Iceberg/IcePackageDefinition.class.st
@@ -10,10 +10,11 @@ Class {
 	#superclass : #IceDefinition,
 	#instVars : [
 		'package',
-		'categories',
-		'path'
+		'path',
+		'packageName',
+		'tagNames'
 	],
-	#category : 'Iceberg-Changes'
+	#category : #'Iceberg-Changes'
 }
 
 { #category : #visiting }
@@ -37,44 +38,30 @@ IcePackageDefinition >> addModification: anIceModification toPatcher: aMCPatcher
 
 { #category : #patching }
 IcePackageDefinition >> addToPatcher: aPatcher [
-	
-	aPatcher addDefinition: (MCOrganizationDefinition categories: categories)
-]
-
-{ #category : #accessing }
-IcePackageDefinition >> asMCDefinition [
-	
-	^ MCOrganizationDefinition categories: categories
-]
 
-{ #category : #accessing }
-IcePackageDefinition >> categories [
-	^ categories
+	aPatcher addDefinition: self asMCDefinition
 ]
 
 { #category : #accessing }
-IcePackageDefinition >> categories: aCollection [
+IcePackageDefinition >> asMCDefinition [
 
-	categories := aCollection
+	^ MCOrganizationDefinition packageName: packageName tagNames: tagNames
 ]
 
 { #category : #accessing }
 IcePackageDefinition >> contents [
-	
-	^ String streamContents: [ :stream |
-		stream nextPutAll:	'Package tags: '.
-		categories do: [ :elem | 
-			stream nextPutAll: String crlf;
-				nextPutAll: String tab;
-				nextPutAll: elem.
-	]]
-]
 
-{ #category : #initialization }
-IcePackageDefinition >> initialize [
-
-	super initialize.
-	categories := #()
+	^ String streamContents: [ :stream |
+		  stream
+			  nextPutAll: 'Package: ';
+			  nextPutAll: self packageName;
+			  crlf;
+			  nextPutAll: 'Tags: '.
+		  self tagNames do: [ :tagName |
+			  stream
+				  nextPutAll: String crlf;
+				  nextPutAll: String tab;
+				  nextPutAll: tagName ] ]
 ]
 
 { #category : #testing }
@@ -89,6 +76,18 @@ IcePackageDefinition >> package [
 	^ package
 ]
 
+{ #category : #accessing }
+IcePackageDefinition >> packageName [
+
+	^ packageName
+]
+
+{ #category : #accessing }
+IcePackageDefinition >> packageName: anObject [
+
+	packageName := anObject
+]
+
 { #category : #accessing }
 IcePackageDefinition >> path [
 	^ path
@@ -107,6 +106,18 @@ IcePackageDefinition >> removeFrom: aVisitor [
 
 { #category : #patching }
 IcePackageDefinition >> removeFromPatcher: aPatcher [
-	
-	aPatcher removeDefinition: (MCOrganizationDefinition categories: categories)
+
+	aPatcher removeDefinition: self asMCDefinition
+]
+
+{ #category : #accessing }
+IcePackageDefinition >> tagNames [
+
+	^ tagNames
+]
+
+{ #category : #accessing }
+IcePackageDefinition >> tagNames: anObject [
+
+	tagNames := anObject
 ]