@GregMorenz

Where in your files does the error appear? I’m not able to reproduce.

Are you using XCode beta 2?

@kivo

Yes, I'm using XCode beta 2 (Version 15.0 beta 2 (15A5161b))

Note it's a runtime error not a compile time one.

The actual error prints in x-code after this line of code, when you click the button:

```
Button("+", action: {modelContext.insert(Item(name: "test", kind: Item.Kind.function))})
```

In the meantime I've learned two new things:

1/5

1) The contents of the init function matters, it's

```
init(name: String, kind: Kind) {
self.name = name
self.kind = kind
}
```

Commenting out `self.kind = kind` avoids the crash.

2) I'm starting this in a DocumentGroup, using a `WindowGroup{ ... }.modelContainer(for: Item.self)` avoids the crash

```
DocumentGroup(editing: Item.self, contentType: .rot) {
ContentView()
}
```

Source follows

2/5

```
import SwiftUI
import SwiftData

@main
struct MainApp: App {
var body: some Scene {
DocumentGroup(editing: Item.self, contentType: .rot) {
ContentView()
}
}
}

struct ContentView: View {
@Environment(\.modelContext) private var modelContext
@Query private var items: [Item]

var body: some View {
Button("+", action: {modelContext.insert(Item(name: "test", kind: Item.Kind.function))})
}
}
```

3/5