RxJava Migration

Migrate RxJava to Kotlin coroutines/flows incrementally. Only invoke this skill when the user explicitly asks to migrate RxJava code. Simple cases map directly; complex cases need a strategy and user input before any code is written.

Step 1: Complexity gate

Classify before writing any migrated code. A chain is Complex if ANY of: nested flatMap/switchMap with an inner Single/Observable; a custom Scheduler; complex error recovery (retryWhen, backoff, retry counts); multi-source zip/combineLatest (3+ sources); Flowable with an explicit backpressure strategy; a Subject shared across classes; or an unclear API return type. Any single Complex criterion makes the whole chain Complex — a two-operator chain with retryWhen is Complex.

Always confirm what each called API returns before migrating — do not assume. A leaf you think is migrated may still return Single/Observable.

Type mapping (state it explicitly — don't silently transform)