⭐ Effects

@ngrx/effects — real source, 388/388 tests passing at addition (404/404 once Operators unblocked provide_effects.spec.ts), 0 lint errors. Adding it against store's already-redesigned Store surfaced exactly the predicted ripple: effects_runner.ts's .subscribe(this.store) (relied on Store implementing Observer<Action>, removed in the redesign) and actions.ts's ScannedActionsSubject typing both needed fixes. EffectSources had the same extends Subject ISP problem as store's classes and was redesigned to composition too — see Composition over Inheritance.

Actions extends Observable<V> was deliberately left alone — its entire contract is being pipeable, with no unrelated method bolted on top, so there's no ISP violation to fix. Code review complete: 18/18 files merged, 0 real bugs found, including a full trace of effect_sources.ts (the highest-risk file in the module) against its own 30-case spec suite. See Code Review Audit.