# Lei Xu > Staff Software Engineer at Airbnb Location: Sunnyvale, California, United States Profile: https://flows.cv/leixu1 ## Work Experience ### Staff Software Engineer @ Airbnb Jan 2018 – Present | San Francisco Bay Area ### Software Engineer @ Yahoo! Inc. Jan 2017 – Jan 2018 | Sunnyvale, CA Tech lead of Yahoo! push notification platform - OnePush, which is a cloud-like service to manage all aspects of notification, streaming, device/app registration and topic subscription for Yahoo's Communication (Mail, Messenger, Flickr), Media Products (Yahoo Newsroom, Finance, Weather, Sports, Fantasy Sports), APAC (TW/HK news, e-commerce) and other Yahoo platforms in multiple channels on a variety of platforms (iOS, Android, ADM, Win10, Browser, email and SMS). - Award for top 10 hacks in Yahoo's 2018 hackday event, truly embraced the spirit of hacking in Yahoo!. Presented hack project (Smart Notification) to global audience on stage (There were 780 hackers across the globe, over 250 hacks were submitted, 40 final hacks were presented). - Engage with APNs new HTTP/2 interface, which can benefit OnePush for universal certification, notification collapse, instant feedback and up to 4K notification payload in iOS. - Browser push. * Align with W3C web push protocol (Chrome and Firefox already support). * Millions of users engage with browser push in Yahoo web pages. * Challenges in browser push include notification content encrypt, application server self-identification by leveraging JWT. - Expand push channels onto Amazon cloud AWS. ### Software Engineer @ Yahoo! Inc. Jan 2015 – Jan 2017 | Sunnyvale, CA Tech lead of Yahoo! push notification platform. - Reward for above-and-beyond, outstanding work on Yahoo! first-ever NFL live streaming, which was using OnePush as the primary mechanism to deliver world-class user experience. Millions of push notification were sent out for game reminding and score updating for this campaign. Thanks to push notification, there were millions concurrent users online for streaming video. - Built a brand new notification SDK, which is modern, robust and developer-friendly. It provides unified APIs across different platforms (iOS, Android and ADM), modernizes OnePush's tech stacks (i.e. engage with FCM and APNs notification center API), brings tens of new features (e.g. faster cold start latency, dual-push channel, in-app messaging, rich app attributes, etc), as well as accurate telemetry to facilitate easy dev-integration, self-troubleshooting and reporting. - Refactor OnePush's architecture to increase membership's accountKey reliability in term of sign-in rate at high 90% (same as Opt-in rate) via new notification SDK's dual-push channel support. - Continuously optimize OnePush to make it more stable in term of large topic (billion scale subscribers) fanout, accelerate OnePush to deliver multiple breaking news alert notifications to hundreds of millions subscribers in single digit minutes without new Capex spend (via smart algorithm, tighter code), which leads the industry. ### Software Engineer, SMS and Push Notification @ Yahoo! Inc. Jan 2013 – Jan 2015 | Beijing City, China - Redesign OnePush to support mail's IMAP-in, which intend to extend its IMAP support by including Gmail, AOL mail, outlook.com and hotmail. The new architecture has the ability to deliver >200K notifications per second. - Topic based notification in OnePush. Properties can send notifications to millions devices within 10 seconds by just one OnePush call. It also providing other features in topic based notification like flexible users segment, dedup and priority to name a few. - Developing OnePush tools in spare time for visualizing user registrations/tags, topic subscriptions and device/app attributes as well as sending notifications without dev involvement, which powers OnePush in areas like self-debugging, troubleshooting and data presentation. It is widely spread among developers, PMs and all OnePush customers. ### Software Engineer, SMS @ Yahoo! Inc. Jan 2013 – Jan 2013 | Beijing City, China Lead Yahoo! SMS platform, provide a rich suite of services using which Yahoo! properties can quickly take SMS products to Market. Our vision is to provide reliable platform service for any Yahoo properties, to receive and send text messages to all mobile devices across the world. - Rout out Yahoo! SMS service and business to cover >200 countries/regions. - Modernization. Move the whole project from RHEL4 to RHEL6 os, which include 5 subsystems, ~200 packages, 12 external/internal dependencies, 200K lines of c++ code rebuild (c++ 11) on RHEL6 OS, 13 new CI jobs (for ~100 hosts/VMs deployment). ### Software Engineer @ Yahoo! Inc. Jan 2011 – Jan 2013 | Beijing City, China Key developer of Yahoo! SMS platform - Athena, which is the next generation mobile messaging platform responsible for receiving and delivering mobile messages (SMS, etc) to and from carriers across the Yahoo! network. - Developing SMS Customer Care tool which is used by Yahoo! customer service to resolve customer requirements in a more convenient and efficient way. - Modernization. Upgrade Yapache (and Yapache modules) from 1.x to 2.2 - Integrate with Yahoo Audience data pipeline - DataHighway rainbow, which can be used to visualize SMS usage, cost per country/region for each Yahoo! property. ## Education ### Master's degree in Computer Science Harbin Institute of Technology ### Bachelor's degree in Computer Science Harbin Institute of Technology ## Contact & Social - LinkedIn: https://linkedin.com/in/lei-xu-hit --- Source: https://flows.cv/leixu1 JSON Resume: https://flows.cv/leixu1/resume.json Last updated: 2026-04-12