Zhilei Zheng
Software Engineer @Pennlabs
To build scalable, beautiful, and performant software for the web and the mobile world. To tackle all software challenges of tomorrow.


  • Junior at University of Pennsylvania studying CIS/NETS
  • Teaching Assistant for UPenn CIS-196: Ruby on Rails
  • Software Engineer at Pennlabs


  • iOS app development with Swift / Objective-C
  • Web development with Ruby and JavaScript
  • Other language skills: Java, Python, C
  • Other skills: Prototyping with Sketch and InvisionApp


RED City (Xiaohongshu) · Mobile Engineer · 2018.5 - 2018.8

  • Implemented homepage feed UI with Texture(AsyncDisplayKit) for iOS
  • Optimized image preloading and managed image decoding operations by reimplementing Texture's ASImageDownloaderProtocol.
  • Optimized feed scrolling performance for Android by replacing TextViews with asynchronously rendered StaticLayouts.
  • Built gesture-aware animations for scrolling events, and raised global engagement and by 2%.

China Unicom · Frontend/Data Engineer · 2017.5 - 2017.8

  • Built a real-time city population analytics dashboard with JavaScript.
  • Created a heatmap by projecting 1km * 1km grids onto the map and assign colors based on real-time data.
  • Implemented various charts for data visualization with D3.js
  • Used Ajax to fetch data and refresh heatmap and graphs every 1 minute.