Senior Android Developer

We are seeking a battle-tested Senior Android Developer to execute a critical, high-priority production release. You will be granted direct repository access on day one and will be responsible for stabilizing our application, resolving legacy technical debt, and implementing new content pipelines to ensure a seamless Google Play Store deployment. KEY RESPONSIBILITIES - Dependency Modernization: Upgrade all third-party libraries and Gradle build scripts to the latest stable versions while maintaining 100% backward compatibility. - Authentication Fix: Diagnose and permanently resolve the Facebook OAuth/Login flow failure, ensuring full compatibility with the latest Facebook SDK and Graph API requirements. - Billing Migration: Execute a full migration from legacy Google Play Billing queries to the new Billing Library v6.0+ (ProductDetails/BillingResult models) without disrupting existing subscriptions or purchase flows. - Stability Engineering: Analyze Firebase Crashlytics data, systematically eliminate all fatal exceptions and ANRs, and drive the crash-free rate to ≥ 99%. - Feature & API Integration: Incorporate new "Subjects" into the app’s data layer and align UI/backend logic with updated ConvertKit naming conventions and tagging structures. TECHNICAL REQUIREMENTS (Must-Haves) - Expert proficiency in Java and the Android SDK (Kotlin experience is a strong plus). - Proven track record with Google Play Billing Library migrations (v4 → v6+). - Deep understanding of Facebook SDK (OAuth flows, hash key validation, and permission scopes). - Advanced working knowledge of the Firebase suite (Crashlytics, Analytics, Firestore/RTDB). LOGISTICS & AVAILABILITY - Must be available to commit 20–40 focused hours per week, starting immediately. - Must be willing to sign a standard Non-Disclosure Agreement (NDA) prior to repository access. - Expectation of proactive, daily communication regarding build status, blockers, and progress reports.