My migration doesn't currently work, but does get called. In my Object file is the below: enum TodoSchemaV1: VersionedSchema { static var models: [any PersistentModel.Type] { [ToDoItem.self] } static var versionIdentifier: String = "Initial version" @Model final class ToDoItem { @Attribute(.unique) var id: String var timestamp: Date var completed: Bool var title: String var info: String init(timestamp: Date, completed: Bool, title: String, info: String) { self.id = UUID().uuidString self.timestamp = timestamp self.completed = completed self.title = title self.info = info } } } enum TodoSchemaV2: VersionedSchema { static var versionIdentifier: String = "Adds priority" static var models: [any PersistentModel.Type] { [ToDoItem.self] } @Model final class ToDoItem { @Attribute(.unique) var id: String var timestamp: Date var completed: Bool var title: String var info: String var priority: Int init(timestamp: Date, completed: Bool, title: String, info: String, priority: Int) { self.id = UUID().uuidString self.timestamp = timestamp self.completed = completed self.title = title self.info = info self.priority = priority } } } enum MigrationPlan: SchemaMigrationPlan { static var schemas: [any VersionedSchema.Type] { [TodoSchemaV1.self, TodoSchemaV2.self] } static var stages: [MigrationStage] { [migrateV1toV2] } static let migrateV1toV2 = MigrationStage.custom(fromVersion: TodoSchemaV1.self, toVersion: TodoSchemaV2.self, willMigrate: { context in guard let todoItemsV1 = try? context.fetch(FetchDescriptor<TodoSchemaV1.ToDoItem>()) else { return } for item in todoItemsV1 { // TODO: Work out how to add the priority value } do { try context.delete(model: TodoSchemaV1.ToDoItem.self) try context.save() } catch { context.rollback() fatalError("Migrating from v1 to v2 failed") } }, didMigrate: nil) } Then where I set up the container container = try ModelContainer(for: [ToDoItem.self], migrationPlan: MigrationPlan.self, ModelConfiguration(for: [ToDoItem.self])) And then that container is passed to my base view