Hao Xu
Verified Expert in Engineering
Full-stack Developer
Hao is a back-end engineer and full-stack veteran with a proven track record of developing services and software solutions for various companies, ranging from small startups to big top-notch corporations. His expertise spans e-commerce, social applications, games, software infrastructures, DevOps, SaaS, and algorithms. Hao is also proficient in big data, AI, and large language models (LLMs) and excels in executing projects and effectively communicating his ideas.
Portfolio
Experience
Availability
Preferred Environment
Linux, Full-stack, Web3, Ruby on Rails (RoR), Python, Go, Java, C++, Cloud, Algorithmic Trading
The most amazing...
...thing I've accomplished is building multiple applications for startups and large systems, supporting companies from their early stages through growth and IPOs.
Work Experience
Tech Lead
Instacart
- Built the full-stack customer platform and front end for web, mobile web, iOS, and Android.
- Architected the chat and recommendation based on ML, OpenAI GPT API, private LLMA, Finetune, RAG, and LangChain.
- Contributed to the infrastructure and DevOps to ensure the Instacart platform ran smoothly.
Tech Leader
Roblox
- Built the microservice infrastructure and DevOps for the Roblox platform.
- Architected the user spammer, user suspicion detection, and prevention system.
- Improved the performance and scalability of the platform to support 10x growth.
Tech Leader
Uber
- Spearheaded the development of the company's global real-time logistic platform for both back-end and client side.
- Built a global intelligence platform tailored for conducting competitive analyses.
- Created the next-generation driver system in Go to achieve a tenfold performance boost compared to the Node.js one.
Senior Engineer
Airbnb
- Built the async process framework based on Kafka and operated it.
- Acted as a full-stack engineer building the dev portal and pipeline.
- Created the infrastructure and DevOps for an Airbnb back end.
Principal Engineer
Citrus Lane
- Built the Citrus Lane website to support 200,000+ users on all platforms—web, iOS, and Android.
- Developed systems to operate 100,000+ monthly subscriptions.
- Created systems for the recurring bills of 100,000+ customers.
Software Engineer
- Built the coupon ads and served billions of audience.
- Architected a pipeline to analyze the performance and results of coupon ads.
- Improved the foundation of the ad display and analytics platform.
Engineer
Yahoo!
- Led a team to build Yahoo email. I built YOS, search, and ads platforms.
- Acted as a full-stack engineer lead and built Yahoo Answers, Flickr, and many other social products.
- Built many Yahoo infrastructure data pipelines and Hadoop stacks.
Principal Engineer
Oracle
- Built and supported the global platform of the Siebel system.
- Architected the infrastructure and comm layer for the Siebel system.
- Developed the analytics platform with a team for the Siebel system.
Experience
Uber | Global Service Platforms
http://www.uber.comI worked for them as a tech lead, spearheading the development of their global real-time logistic platform, their global intelligence platform for competitive analyses, and the next-generation driver system.
Airbnb | Product and Service Infrastructure and Data Flow
http://www.airbnb.comI integrated the team as a senior engineer and tech lead, contributing to the product and service infrastructure and the communication and data flow within the company's systems.
Google | Ads Project
http://www.google.comI joined the project to combine the power of search and ads with AI technology, working on the ads UI and developing coupon ads.
Roblox | Platform Architecture
http://www.robloxI worked at Roblox as a tech lead, handling their next-generation platform's architecture, development, and maintenance, moving from a monolithic to a microservice architecture.
Citrus Lane | Back-end Infrastructure, Website, and Apps
I joined them as a tech leader, leading the team to build the back-end infrastructure, website, and apps.
Siebel | Cross-platform Functionality
I played a crucial role in developing the cross-platform functionality for Siebel, enabling seamless operation on Linux, IBM AIX, and Microsoft Windows, with support for multiple databases, including IBM Db2, Oracle, and Microsoft SQL Server.
Subsequently, Siebel was acquired by Oracle, marking a significant milestone in its history.
Yahoo | Platform, Infrastructure, and Data Storage Systems
http://www.yahoo.comI worked at Yahoo as a principal engineer and tech lead, contributing to multiple tasks regarding the platform, infrastructure, and cloud data storage systems.
Algorithm Trading System
Student Class Selection System
Finance, Legal, and Web Scrap Project
Trading Bots
They could plug in the specific algorithms.
Education
Master's Degree in Computer Science
The University of New Mexico - Albuquerque, New Mexico, USA
Bachelor's Degree in Computer Science
Tsinghua University - Beijing, China
Skills
Libraries/APIs
Node.js, Stripe, Stripe API, NumPy, React, Interactive Brokers API, TWS API, Reddit API, Rails Engines, Beautiful Soup, OpenAI Assistants API, Gmail API, Authorize.net, Vue, Python API
Tools
Logging, Amazon Elastic Container Service (Amazon ECS), AWS Key Management Service (KMS), Terraform, HashiCorp, Cloud Dataflow, Git, GDB, CMake, GitHub, RabbitMQ, ChatGPT, Google Analytics, Docker Hub, BigQuery, Cron, Android Studio, Expo, Azure Active Directory B2C (ADB2C), Hashistack, Keycloak, Apache Beam, AWS IAM
Frameworks
Ruby on Rails (RoR), .NET, Cascades, Django, Boost, Laravel, ASP.NET, gRPC, Spark, Apache Thrift, Qt, Express.js, Selenium, Scrapy, Bootstrap, .NET Core, LlamaIndex, Tailwind CSS, Flutter, React Native, OAuth 2, IdentityServer 4, Next.js, Angular
Languages
Python, Go, Java, C++, Ruby, JavaScript, HTML, PHP, GraphQL, SQL, C#, TypeScript, CSS, C, Snowflake, Scala, Perl, Kotlin, Swift, SAML, Rust, Embedded C, Python 3, Pine Script
Paradigms
DevOps, Hosting, Microservices, ETL, API Architecture, Continuous Integration (CI), Data Science, Search Engine Optimization (SEO), Business Intelligence (BI), Serverless Architecture, Cross-platform, Mobile Development
Platforms
Linux, Apache Kafka, Docker, WordPress, Amazon Web Services (AWS), Google Cloud Platform (GCP), Firebase, BigCommerce, DigitalOcean, Heroku, Mobile, iOS, Android, Mapbox, Azure, Blockchain, Kubernetes, Windows, Neto, Wand
Storage
MySQL, PostgreSQL, NoSQL, Redshift, Data Pipelines, Data Lakes, Cassandra, Redis, MongoDB, Google Cloud, Elasticsearch, Amazon DynamoDB, ClickHouse
Other
Software Development, Software, Full-stack, Cloud, Distributed Systems, Machine Learning, Competitive Intelligence, Infrastructure, SaaS, Cloudflare, Architecture, Optimization, Servers, Platform as a Service (PaaS), Web Scraping, APIs, CI/CD Pipelines, Data Structures, Algorithms, Data Engineering, Orchestration, Webhooks, Linear Algebra, Data Scraping, Web Development, OpenAI, System Design, Back-end, OpenAI GPT-3 API, OpenAI GPT-4 API, Stripe Payments, Artificial Intelligence (AI), AI Programming, Data Scientist, Retrieval-augmented Generation (RAG), Generative Pre-trained Transformers (GPT), Web Services, Deep Learning, Data Analytics, Blade Templates, Scraping, eCommerce, Back-end Development, Large Language Models (LLMs), MERN Stack, CTO, Bots, Cloud Infrastructure, Full-stack Development, Reddit, Google Drive, Integration, Content Management Systems (CMS), API Integration, Google Cloud Functions, Trading, TradingView, Cryptocurrency, Prompt Engineering, Gmail, Email, SDK Development, SDKs, Serverless, Pinecone, Poetry, Computer Networking, Datagram Transport Layer Security (DTLS), Software Engineering, Software Architecture, Navigation, Electric Vehicles, Fivetran, Identity & Access Management (IAM), OpenID Connect (OIDC), Duende, SAML-auth, SecOps, Dynamic Load Balancing, Plugins, PKI, GPT, LangChain, DDS, Algorithmic Trading, PDF Scraping, Midjourney, Strapi, Web3, Analysis, Dashboards, AI Website Builders
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