Typed Error Handling (Kotlin / KMP)

Overview

In shared KMP code, prefer modeling expected failures as values over throwing across layers — it forces callers to handle them and crosses the iOS boundary cleanly. Three idiomatic tiers: kotlin.Result, sealed result types, and Arrow (Either/Raise).

When to use

• Designing how a repository or use case reports failure
• Network / parse / validation outcomes
• Deciding between exceptions, Result, sealed types, or Arrow
• Surfacing errors to Swift across the KMP boundary

Decision