Official account of the Xianyu technology team
This article details Xianyu's engineering journey to replace third‑party live‑streaming SDKs with a custom, Flutter‑based cross‑platform solution that addresses customization difficulty, platform consistency, and log tracing while outlining design principles, module implementations, and performance outcomes.
By leveraging existing middle‑platform services and a lightweight, configurable discount component, Xianyu rapidly built a full‑scale Double 11 marketing discount system—covering merchant recruitment, unified discount calculation, pre‑heat visuals, and robust load‑testing—delivering a stable promotion platform that can be reused for future campaigns.
During IdleFish’s 2023 Double 11 promotion, engineers tackled massive traffic spikes by running feature‑flag, launch‑side, and mitmproxy‑based disaster‑recovery rehearsals, boosted performance with increased first‑screen modules, CSS‑only animations, pre‑fetching and offline caching, introduced a PHA container for seamless tab switching, and optimized deep‑link handling for external channels, while planning further SSR and stability automation.
The Xianyu team’s talk outlines Flutter performance challenges—complex list‑item logic, a 16.6 ms frame budget, DynamicX template overhead, and scroll‑curve‑induced offset jumps—and presents best‑practice solutions such as PowerScrollView caching, partial refresh, frame‑splitting, DynamicX caching, isolate offloading, layer merging, plus custom benchmarking, DevTools extensions, and FlutterBlockCanary for measurement, urging developers to prioritize perceived smoothness, monitor raster costs, and leverage multi‑threading and community updates.
The platform listens to GitLab change events, parses Java, ObjC, and Flutter diffs to locate modified methods, maps those methods to entry HTTP/RPC interfaces using recorded traffic call chains, and automatically selects corresponding regression test cases, dramatically cutting testing effort while enabling future risk analysis.
Fish_redux 3.0 refactors the framework by collapsing deep inheritance into a BasicComponent base, trimming code from over 3 k to about 1 k lines, streamlining context handling, and preserving core state‑driven UI, middleware, and assembly‑style componentization while adding lightweight extension packages and a roadmap for further Flutter and Dart 2.x enhancements.
Taobao’s Double 11 showcased a suite of advanced technologies—including 3D immersive XR live rooms, large‑scale multimodal product search, ultra‑low‑latency streaming, AI‑driven content moderation, and low‑carbon model compression—demonstrating how e‑commerce can innovate while promoting sustainability and inclusivity.
Xianyu’s deep‑linking system uses custom URL schemes and iOS universal links to wake up the app, detects success, falls back to store or APK downloads, restores original parameters after install, auto‑fills tracking fields via an SDK, reports funnel metrics, and provides a reusable module for all external traffic scenarios.
PowerImage combines FFI and external‑texture techniques to deliver native‑like Flutter image handling, offering direct ui.Image loading, unified caching, simulator support, custom channels and comprehensive error capture, with texture‑based rendering preferred for typical use and FFI reserved for legacy simulators or direct pixel access, while providing performance gains and upcoming animated‑image support.
The migration of Xianyu’s legacy Idlecenter service split into code migration—defining clear RPC‑service boundaries, moving middleware together, and avoiding refactoring—and traffic migration using HSF routing to shift load transparently, enabling gray releases, observability, sub‑second rollbacks, cutting effort to one person‑week per service with zero faults and a reusable checklist.
