🚀 About Flipster Flipster(flipster.io) is a high-performance crypto perpetuals trading platform on a mission to create the most efficient, frictionless, and high-performance trading experience. Engineered by traders and optimized for trading, Flipster combines zero spreads, instant execution, and capital efficiency to deliver a platform where performance is the product. Operating globally and serving users in nearly 200 countries, Flipster is built for crypto traders who demand the ultimate perpetual trading experience — from active retail users to degens to seasoned pros — while maintaining the highest standards of compliance and security.  About this role We're hiring a mobile networking specialist based in mainland China to own the SDK-level connectivity layer for our iOS and Android apps in the region. This is an engineering role focused on transport-layer logic, connection management, and client-side resilience strategies for users in challenging network environments. REQUIRED EXPERIENCE 4+ years of mobile SDK development on iOS or Android (both preferred) with significant time spent on the networking layer Direct hands-on experience shipping apps to mainland China users with measurable reliability improvements you can describe Strong understanding of TLS, TCP behavior, and modern transport protocols (HTTP/2, HTTP/3, QUIC, WebSocket) Comfortable with Wireshark, tcpdump, Charles, and platform-specific network debugging tools Based in mainland China and able to test directly against real regional network conditions PREFERRED Experience at fintech, exchange, streaming, or gaming companies with mainland China users Familiarity with native networking stacks (NSURLSession, OkHttp, Cronet) and how to customize them Background in protocol design or transport-layer optimization HIRING PROCESS CV/Resume submission 1st round interview 2nd round interview * What you'll have access to A real, hard, well-resourced problem. A team that respects deep network expertise. Autonomy on architecture and protocol decisions. Direct impact on user experience for our entire mainland China user base.