SwiftData Decimal loses precision after save/fetch with a minimal reproduction

I believe I may have found a SwiftData persistence bug, but I'd like to verify that I'm not overlooking a documented limitation before filing Feedback.

This minimal example appears to lose precision when persisting a Decimal:

import Foundation
import SwiftData

@Model
class Item {
    var value: Decimal

    init(_ value: Decimal) {
        self.value = value
    }
}

let original = Decimal(string: "123456789012345.6")!

let container = try ModelContainer(
    for: Item.self,
    configurations: .init(isStoredInMemoryOnly: true)
)

let context = ModelContext(container)
context.insert(Item(original))
try context.save()

let fetched = try ModelContext(container)
    .fetch(FetchDescriptor<Item>())
    .first!

print(original)
print(fetched.value)

Output:

123456789012345.6
123456789012346

A few observations from additional testing:

• Decimal(string:) preserves the value before persistence.
• Decimal ↔ NSDecimalNumber bridging preserves the value in separate tests.
• The value remains exact after model initialization, insertion, and save() on the registered object.
• The first Swift-visible precision loss appears after fetching from a new ModelContext.
• As a control, I repeated the test using Core Data with an NSInMemoryStoreType store and an NSDecimalAttributeType attribute. That round-tripped the tested values exactly.
• Inspecting the SQLite store generated by SwiftData showed the affected value stored as a REAL.

At this point it appears the precision loss occurs somewhere in the SwiftData/Core Data persistence pipeline rather than in Decimal itself.

Can anyone reproduce this, or is there a documented limitation on Decimal persistence in SwiftData that I have missed?

If this is expected behavior, what is the recommended way to persist exact decimal values for financial applications?