Hao is available for hire
Hire HaoHao Xu
Verified Expert in Engineering
Full-stack Developer
Palo Alto, CA, United States
Toptal member since September 5, 2023
Bio
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 eCommerce, 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
Imagemakers Inc.
Symfony, PHP, Git, Amazon Web Services (AWS), CSS, HTML, AngularJS, Amazon EC2...
Dealermade LP
ZIO, Scala, Profiling, Java Development Kit (JDK), JavaFX, Monitoring...
Instacart
Ruby, JavaScript, Amazon Web Services (AWS), OpenAI, Back-end, OpenAI GPT-3 API...
Experience
- Java - 10 years
- C++ - 10 years
- Distributed Systems - 10 years
- Python - 9 years
- Node.js - 8 years
- Ruby on Rails (RoR) - 8 years
- Go - 8 years
- Machine Learning - 7 years
Availability
Full-time
Preferred Environment
Full-stack, Web3, Ruby on Rails (RoR), Python, Go, Java, C++, Cloud, JavaScript, 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
Back-end Symfony and AWS Developer
2024 - 2024
Imagemakers Inc.
- Built many new features according to business requirements and KTLO.
- Guided and built the spammer/reCAPTCHA verification to fight against spammers.
- Oversaw the Symfony framework maintenance work and deployment flow.
- Developed new emails and enhanced a new search capability.
Technologies: Symfony, PHP, Git, Amazon Web Services (AWS), CSS, HTML, AngularJS, Amazon EC2, Amazon S3 (AWS S3), Concurrency, Containerization, Google Sheets, Automation, NGINX, Azure Kubernetes Service (AKS), Middleware, Oracle, Relational Database Services (RDS), Datadog, SSH, Wix, Macros, Robotic Process Automation (RPA)
Senior Scala Developer | Zio Framework Expert
2024 - 2024
Dealermade LP
- Diagnosed and provided guidelines for the performance and scalability issues of the ZIO/Scala framework.
- Developed a Scala async framework solution to scale up/out the current system.
- Provided a new architecture, roadmap, and operation process/documents for the company to use in future development.
Technologies: ZIO, Scala, Profiling, Java Development Kit (JDK), JavaFX, Monitoring, API Observability, Observability Tools, Git, Containers, Amazon, Apache Ant, IntelliJ IDEA, Trading Bots, Big Data, Big Data Architecture, Concurrency, Containerization, Google Sheets, Automation, Google API, NGINX, Azure Kubernetes Service (AKS), Azure Traffic Manager, Image Generation, Elastic, Middleware, RxJava, Spring, Unix, AWS Lambda, API Connectors, Cloud Architecture, PDF, Object-oriented Programming (OOP), JVM, Relational Database Services (RDS), Datadog, SSH, Google Cloud, SnapLogic, System Integration, Salesforce, Workflow Automation, FTP, Third-party APIs
Tech Lead
2020 - 2022
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.
- Served as a tech leader in building the Instcart eCommerce platform with Ruby on Rails and GraphQL, the world's biggest Ruby on Rail deployment.
- Architected and built a user authentication platform in Go, serving hundreds of millions of users.
- Built a central authentication system to support hundreds of millions of users.
Technologies: Ruby, JavaScript, Amazon Web Services (AWS), OpenAI, Back-end, OpenAI GPT-3 API, OpenAI GPT-4 API, Linux, Stripe API, Stripe Payments, Artificial Intelligence (AI), AI Programming, Data Scientist, Retrieval-augmented Generation (RAG), Generative Pre-trained Transformers (GPT), Continuous Integration (CI), Web Services, Data Science, GitHub, Deep Learning, Data Analytics, NumPy, RabbitMQ, Laravel, Blade Templates, React, ChatGPT, Midjourney, Firebase, TypeScript, CSS, Scraping, eCommerce, Google Analytics, Search Engine Optimization (SEO), gRPC, Snowflake, Back-end Development, Redis, Spark, Large Language Models (LLMs), Express.js, MERN Stack, MongoDB, Google Cloud, Bots, Cloud Infrastructure, Selenium, Full-stack Development, Docker Hub, Reddit API, Reddit, PostgreSQL, BigQuery, Business Intelligence (BI), Rails Engines, Google Drive, Content Management Systems (CMS), API Integration, Beautiful Soup, Google Cloud Functions, Cron, Elasticsearch, OpenAI Assistants API, Prompt Engineering, Gmail API, Gmail, Email, SDK Development, SDKs, Amazon DynamoDB, Serverless Architecture, Serverless, Pinecone, LlamaIndex, Poetry, Computer Networking, Software Engineering, Tailwind CSS, Android Studio, Cross-platform, Mobile Development, Mobile, Software Architecture, iOS, Android, Kotlin, Flutter, React Native, Swift, Mapbox, Navigation, Electric Vehicles, Fivetran, Expo, Azure, Identity & Access Management (IAM), Azure Active Directory B2C (ADB2C), OpenID Connect (OIDC), SAML, OAuth 2, Duende, IdentityServer 4, SAML-auth, SecOps, Next.js, Hashistack, AI Website Builders, Mobile App Development, Leadership, Scalability, Technical Leadership, Startups, Coaching, Engineering, Process Development, Project Management, Azure OpenAI Service, Blazor, Load Testing, Web Scalability, Amazon Simple Queue Service (SQS), Kafka Streams, Google Analytics 4, Microsoft Power Apps, SharePoint, Office 365, Office 365 API, APIs, REST APIs, CTO, PWA, Progressive Web Applications (PWAs), Electron, Algolia, Gemini API, DNS, SEO Tools, Django, Spring Boot, Pandas, Google Sheets API, Hardware, Low-level Programming, MacOS, MDM, Jamf, Mobile Device Management (MDM), Zapier, Scala, ZIO, Profiling, Amazon EC2, Amazon S3 (AWS S3), AngularJS, RSpec, Solidus, Java Development Kit (JDK), JavaFX, Accessibility, Shopify, Django REST Framework, Monitoring, Machine Learning Operations (MLOps), Databricks, OpenTelemetry, Apache Spark, API Observability, Data Warehousing, Amazon SageMaker, Prometheus, Observability Tools, Website Data Scraping, Dart, GStreamer, Git, JSON, XML, Jakarta Server Pages (JSP), Containers, Stable Diffusion, ElevenLabs Solutions, Chatbots, Live Chat, Crawlee, Amazon, HIPAA Compliance, Apache Tomcat, Apache Ant, IntelliJ IDEA, Zendesk, NoSQL, Cassandra, Python API, Big Data, Big Data Architecture, Data Cleansing, Data Handling, Concurrency, Generative Artificial Intelligence (GenAI), OpenAI API, Containerization, Google Sheets, Google Apps Script, Automation, Google API, NGINX, Flask, CheerioJS, Goutte, FastAPI, Python Asyncio, Performance Tuning, WebSockets, Asyncio, Azure Kubernetes Service (AKS), Azure Traffic Manager, Time Series Modeling, GTK, HTML5, Image Generation, Automated Testing, PagerDuty, Testing, SOC 2, Google Maps, Google Maps SDK, Mapbox SDK, Mapbox API, Figma, MongoDB Atlas, Elastic, Middleware, Jetpack Compose, RxJava, MVC Frameworks, Quarkus, Spring, Large Scale Distributed Systems, Single Sign-on (SSO), Technical Architecture, Technical Writing, Mobile Apps, Redux, Babel, Large-scale Projects, Webpack, Unix, WildFly, Oracle, AWS Lambda, Microsoft Power Platform, Microsoft Power Pages, Microsoft Power BI, Social Security, IDP, API Connectors, Cloud Architecture, Airtable, PDF, Object-oriented Programming (OOP), Microservices Architecture, Front-end, JVM, Team Leadership, Relational Database Services (RDS), Embedded C++, Embedded Linux, NCR API, Point of Sale, PostgREST, Toast (Point-of-sale Platform), Clover POS, Lightspeed, Revel POS, Square Payment Gateway, Datadog, Natural Language Processing (NLP), Speech Recognition, Security, Amazon Cognito, Auth0, Multi-factor Authentication (MFA), SSH, Retool, System Integration, Microsoft Copilot, Workflow Automation, Vanilla JS, FTP, Third-party APIs, Macros, Visual Basic for Applications (VBA), Excel VBA, Excel Macros, Robotic Process Automation (RPA)
Tech Lead
2019 - 2020
Roblox
- Built the microservice infrastructure and DevOps for the Roblox platform.
- Architected the user spammer, user suspicion detection, and prevention system.
- Improved the platform's performance and scalability to support 10x growth.
- Built next-generation mesh services in Go, handling millions of queries per second and serving hundreds of millions of users.
Technologies: AWS IAM, Neto, OpenAI, Machine Learning, Infrastructure, Cloud, System Design, Linux, GNU Debugger (GDB), Boost, CMake, Stripe API, Artificial Intelligence (AI), Continuous Integration (CI), Web Services, C#, GitHub, Deep Learning, Data Analytics, NumPy, RabbitMQ, ASP.NET, gRPC, Snowflake, Back-end Development, Redis, Spark, Apache Thrift, Qt, Google Cloud, Bots, Cloud Infrastructure, Docker Hub, BigQuery, Integration, Content Management Systems (CMS), Cron, Elasticsearch, Gmail API, Gmail, Email, Back-end, .NET Core, SDK Development, SDKs, Amazon DynamoDB, Serverless Architecture, Serverless, Computer Networking, Software Engineering, Android Studio, Cross-platform, Mobile Development, Mobile, Software Architecture, iOS, Android, Swift, Azure, Identity & Access Management (IAM), Azure Active Directory B2C (ADB2C), OpenID Connect (OIDC), SAML, OAuth 2, Duende, IdentityServer 4, SAML-auth, SecOps, Next.js, Hashistack, Leadership, Scalability, Technical Leadership, Startups, Coaching, Engineering, Process Development, Project Management, Azure OpenAI Service, Blazor, Load Testing, Web Scalability, Amazon Simple Queue Service (SQS), Kafka Streams, Google Tag Manager, Google Analytics 4, Microsoft Power Apps, SharePoint, Office 365, Office 365 API, APIs, REST APIs, CTO, PWA, Progressive Web Applications (PWAs), DNS, SEO Tools, HubSpot, Pandas, Google Sheets API, Windows, Low-level Programming, MacOS, MDM, Mobile Device Management (MDM), Profiling, Amazon EC2, Amazon S3 (AWS S3), Java Development Kit (JDK), Embedded Rust, Embedded Systems, Accessibility, Shopify, PySide, Monitoring, Machine Learning Operations (MLOps), Databricks, OpenTelemetry, Apache Spark, API Observability, Data Warehousing, Amazon SageMaker, Prometheus, Observability Tools, Website Data Scraping, Dart, GStreamer, Git, JSON, XML, Crypto, Containers, JSII, ElevenLabs Solutions, Amazon, FileZilla, HIPAA Compliance, HL7, PuTTY, Agile Software Development, IntelliJ IDEA, NoSQL, Cassandra, Python API, Big Data, Big Data Architecture, Data Cleansing, Data Handling, Containerization, Embedded Software, Google Sheets, Google Apps Script, Automation, Google API, NGINX, Flask, FastAPI, Python Asyncio, Performance Tuning, WebSockets, Asyncio, Azure Kubernetes Service (AKS), Time Series Modeling, GTK, HTML5, Kubernetes, Automated Testing, PagerDuty, Testing, SOC 2, Go, Google Maps, Google Maps SDK, MongoDB Atlas, Elastic, Middleware, .NET MAUI, Xamarin, Jetpack Compose, jQuery, MVC Frameworks, Large Scale Distributed Systems, Single Sign-on (SSO), Technical Architecture, Technical Writing, Visual Studio, Mobile Apps, Babel, Large-scale Projects, Webpack, Hibernate, Unix, Oracle, AWS Lambda, Microsoft Power Platform, Microsoft Power Pages, Social Security, Airtable, PDF, Object-oriented Programming (OOP), Microservices Architecture, JVM, Team Leadership, Relational Database Services (RDS), Embedded C++, Embedded Linux, Embedded Development, Datadog, Natural Language Processing (NLP), Apache ZooKeeper, Security, Games, Amazon Cognito, Auth0, Multi-factor Authentication (MFA), SSH, Retool, SnapLogic, System Integration, Salesforce, Microsoft Copilot, Workflow Automation, Vanilla JS, ASP.NET MVC, FTP, Microsoft SQL Server, Razor, AspDotNetStorefront, Visual Basic for Applications (VBA), Excel VBA, Excel Macros, Robotic Process Automation (RPA)
Tech Lead
2016 - 2019
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.
Technologies: C++, Java, Go, Node.js, Cloudflare, Architecture, Logging, WordPress, Optimization, Servers, Hosting, Dynamic Load Balancing, Microservices, Platform as a Service (PaaS), Plugins, Rust, Blockchain, Web Scraping, APIs, ETL, Django, Redshift, Amazon Web Services (AWS), Amazon Elastic Container Service (ECS), ClickHouse, PKI, CI/CD Pipelines, AWS Key Management Service (KMS), Terraform, HashiCorp, Keycloak, GraphQL, Data Structures, SQL, Algorithms, Data Pipelines, Data Engineering, Data Lakes, Cloud Dataflow, Google Cloud Platform (GCP), Orchestration, LangChain, Apache Beam, Webhooks, API Architecture, Linear Algebra, Data Scraping, Web Development, Machine Learning, Git, Linux, GNU Debugger (GDB), Boost, DDS, CMake, Stripe API, Stripe Payments, Artificial Intelligence (AI), AI Programming, Data Scientist, Continuous Integration (CI), Web Services, Data Science, GitHub, Data Analytics, NumPy, RabbitMQ, PDF Scraping, Laravel, Blade Templates, React, Firebase, TypeScript, CSS, Scraping, eCommerce, BigCommerce, Google Analytics, Search Engine Optimization (SEO), gRPC, C, Snowflake, Back-end Development, Cassandra, Redis, Spark, Apache Thrift, Embedded C, Express.js, MERN Stack, MongoDB, Google Cloud, Bots, Cloud Infrastructure, Selenium, Full-stack Development, Docker Hub, Reddit, PostgreSQL, BigQuery, Business Intelligence (BI), Google Drive, Bootstrap, Content Management Systems (CMS), Strapi, API Integration, Beautiful Soup, Google Cloud Functions, Cron, Elasticsearch, Gmail API, Gmail, Email, Back-end, SDK Development, SDKs, Amazon DynamoDB, Serverless Architecture, Serverless, Computer Networking, Datagram Transport Layer Security (DTLS), Software Engineering, Android Studio, Cross-platform, Mobile Development, Mobile, Software Architecture, iOS, Android, Flutter, React Native, Swift, Mapbox, Navigation, Electric Vehicles, Expo, Identity & Access Management (IAM), OpenID Connect (OIDC), SAML, OAuth 2, SAML-auth, SecOps, Hashistack, Mobile App Development, Buffer Management, Leadership, Scalability, Technical Leadership, Startups, Coaching, Engineering, Process Development, Project Management, Load Testing, Web Scalability, Amazon Simple Queue Service (SQS), Kafka Streams, Google Ads, Google Tag Manager, Google Analytics 4, REST APIs, CTO, PWA, Progressive Web Applications (PWAs), DNS, htaccess, SEO Tools, HubSpot, Spring Boot, Pandas, Google Sheets API, C#, Low-level Programming, MacOS, Jamf, Mobile Device Management (MDM), Zapier, Profiling, Amazon EC2, Amazon S3 (AWS S3), AngularJS, Java Development Kit (JDK), JavaFX, Embedded Systems, Internet of Things (IoT), Accessibility, Shopify, Django REST Framework, Django ORM, PyQt, PySide, Monitoring, Machine Learning Operations (MLOps), Databricks, OpenTelemetry, Apache Spark, API Observability, Data Warehousing, Amazon SageMaker, Prometheus, Observability Tools, Website Data Scraping, Dart, GStreamer, JSON, XML, Crypto, Containers, JSII, Marketing Technology (MarTech), Crawlee, Amazon, FileZilla, HIPAA Compliance, HL7, PuTTY, Agile Software Development, Apache Tomcat, Apache Ant, IntelliJ IDEA, Apache Struts 2, NetBeans, Zendesk, NoSQL, Big Data, Big Data Architecture, Data Cleansing, Data Handling, Concurrency, Containerization, Google Sheets, Google Apps Script, Automation, Google API, NGINX, Flask, CheerioJS, Goutte, FastAPI, Python Asyncio, Performance Tuning, WebSockets, Asyncio, Azure Kubernetes Service (AKS), Azure Traffic Manager, Time Series Modeling, GTK, HTML5, Kubernetes, Automated Testing, PagerDuty, Testing, SOC 2, Google Maps, Google Maps SDK, Mapbox SDK, Mapbox API, Figma, Elastic, Middleware, Jetpack Compose, RxJava, jQuery, Apache, Spring, Large Scale Distributed Systems, Single Sign-on (SSO), Technical Architecture, Mobile Apps, XHTML, Redux, Babel, Large-scale Projects, Webpack, Unix, WildFly, Oracle, AWS Lambda, Microsoft Power Platform, Microsoft Power Pages, Microsoft Power Automate, Microsoft Power BI, Social Security, IDP, API Connectors, Cloud Architecture, Airtable, PDF, Object-oriented Programming (OOP), Microservices Architecture, Front-end, JVM, Team Leadership, Relational Database Services (RDS), Embedded C++, TouchGFX, NCR API, Point of Sale, PostgREST, Toast (Point-of-sale Platform), Clover POS, Lightspeed, Revel POS, Square Payment Gateway, Datadog, Natural Language Processing (NLP), Speech Recognition, Apache ZooKeeper, Security, Amazon Cognito, Auth0, Multi-factor Authentication (MFA), SSH, Retool, SnapLogic, System Integration, Microsoft Copilot, Workflow Automation, Vanilla JS, FTP, Macros, Excel VBA, Excel Macros, Robotic Process Automation (RPA)
Senior Engineer
2017 - 2018
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.
- Built the world's biggest travel eCommerce marketplace with Ruby on Rails and Java/Go.
Technologies: Ruby, Java, Machine Learning, Amazon Web Services (AWS), Apache Kafka, Linux, Boost, CMake, Stripe API, Stripe Payments, Data Scientist, Continuous Integration (CI), Web Services, GitHub, Data Analytics, NumPy, RabbitMQ, Firebase, TypeScript, CSS, eCommerce, Google Analytics, Search Engine Optimization (SEO), Snowflake, Angular, Back-end Development, Cassandra, Scala, Redis, Spark, Apache Thrift, Google Cloud, Heroku, Bots, Cloud Infrastructure, Selenium, Full-stack Development, Docker Hub, Rails Engines, Google Drive, Scrapy, Integration, API Integration, Beautiful Soup, Google Cloud Functions, Cron, Elasticsearch, Gmail API, Email, Back-end, SDK Development, SDKs, Amazon DynamoDB, Serverless Architecture, Serverless, Computer Networking, Software Engineering, Android Studio, Cross-platform, Mobile Development, Mobile, Software Architecture, iOS, Android, Kotlin, Flutter, React Native, Swift, Mapbox, Navigation, Expo, OpenID Connect (OIDC), SAML, OAuth 2, SAML-auth, SecOps, Mobile App Development, Scalability, Startups, Coaching, Engineering, Process Development, Project Management, Load Testing, Web Scalability, Amazon Simple Queue Service (SQS), Kafka Streams, Google Tag Manager, Google Analytics 4, Office 365, APIs, REST APIs, PWA, Progressive Web Applications (PWAs), GoDaddy, SEO Tools, HubSpot, Spring Boot, Pandas, MacOS, Mobile Device Management (MDM), Profiling, Amazon EC2, Amazon S3 (AWS S3), RSpec, Solidus, Java Development Kit (JDK), Accessibility, Monitoring, Machine Learning Operations (MLOps), Databricks, OpenTelemetry, Apache Spark, API Observability, Data Warehousing, Prometheus, Observability Tools, Git, JSON, XML, Jakarta Server Pages (JSP), Containers, Alibaba Cloud, HIPAA Compliance, Agile Software Development, Apache Ant, IntelliJ IDEA, Apache Struts 2, Zendesk, NoSQL, Python API, Big Data, Big Data Architecture, Data Cleansing, Data Handling, Concurrency, Containerization, Embedded Software, Google Sheets, Google Apps Script, Automation, Google API, NGINX, Flask, FastAPI, Python Asyncio, Performance Tuning, WebSockets, Asyncio, Azure Kubernetes Service (AKS), DNS, Time Series Modeling, GTK, HTML5, Automated Testing, PagerDuty, Testing, SOC 2, Google Maps, Elastic, Middleware, Apache, MVC Frameworks, MariaDB, Quarkus, Spring, Large Scale Distributed Systems, Single Sign-on (SSO), Technical Architecture, Technical Writing, Mobile Apps, XHTML, Redux, Babel, Large-scale Projects, Webpack, Hibernate, Unix, WildFly, Oracle, Microsoft Power Pages, Microsoft Power Automate, Microsoft Power BI, IDP, API Connectors, Cloud Architecture, Airtable, PDF, Object-oriented Programming (OOP), Microservices Architecture, Front-end, JVM, Relational Database Services (RDS), Embedded C++, SLAM, Simultaneous Localization & Mapping (SLAM), Natural Language Processing (NLP), Speech Recognition, Apache ZooKeeper, Auth0, Multi-factor Authentication (MFA), Retool, Vanilla JS, Microsoft SQL Server, Visual Basic for Applications (VBA), Excel VBA, Robotic Process Automation (RPA)
CTO
2013 - 2015
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.
Technologies: PHP, Node.js, BigCommerce, Back-end Development, Redis, Express.js, MERN Stack, MongoDB, CTO, Google Cloud, Heroku, Bots, Cloud Infrastructure, Selenium, Full-stack Development, Business Intelligence (BI), Perl, Scrapy, Integration, Bootstrap, Content Management Systems (CMS), Strapi, API Integration, Beautiful Soup, Google Cloud Functions, Elasticsearch, Email, .NET Core, SDK Development, Software Engineering, Mobile, Software Architecture, iOS, Android, Authorize.net, OAuth 2, SecOps, CTools, Leadership, Technical Leadership, Startups, Coaching, Process Development, Project Management, Load Testing, Web Scalability, Google Ads, Google Tag Manager, Google Analytics 4, Office 365, Office 365 API, APIs, PWA, Progressive Web Applications (PWAs), htaccess, GoDaddy, SEO Tools, HubSpot, MacOS, Symfony, Amazon EC2, Accessibility, Magento, Django REST Framework, Django ORM, PyQt, Monitoring, Data Warehousing, Observability Tools, Git, JSON, XML, Jakarta Server Pages (JSP), Containers, Marketing Technology (MarTech), Alibaba Cloud, eBay, HIPAA Compliance, HL7, PuTTY, Agile Software Development, Apache Ant, IntelliJ IDEA, Apache Struts 2, NetBeans, Python API, Big Data Architecture, Data Cleansing, Data Handling, Concurrency, Containerization, Embedded Software, Google API, NGINX, Performance Tuning, Asyncio, Azure Kubernetes Service (AKS), Azure Traffic Manager, DNS, GTK, HTML5, Image Generation, Automated Testing, Testing, Elastic, Middleware, jQuery, MVC Frameworks, MariaDB, Quarkus, Spring, Technical Architecture, Technical Writing, Mobile Apps, XHTML, Redux, Large-scale Projects, Hibernate, Unix, WildFly, Oracle, Microsoft Power Platform, Microsoft Power Pages, Microsoft Power BI, Cloud Architecture, PDF, Object-oriented Programming (OOP), Microservices Architecture, Front-end, JVM, Team Leadership, Relational Database Services (RDS), Embedded C++, SLAM, Simultaneous Localization & Mapping (SLAM), Embedded Development, PostgREST, Natural Language Processing (NLP), Apache ZooKeeper, Security, Sports, Auth0, Wix, SnapLogic, System Integration, ASP.NET MVC, Microsoft SQL Server, Razor, Visual Basic for Applications (VBA), Robotic Process Automation (RPA)
Software Engineer
2012 - 2012
- 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.
Technologies: Java, C++, JavaScript, Algorithms, Linux, GNU Debugger (GDB), Boost, CMake, Artificial Intelligence (AI), Data Scientist, Web Services, Data Science, GitHub, Search Engine Optimization (SEO), gRPC, C, Back-end Development, Cloud Infrastructure, Business Intelligence (BI), Google Drive, Integration, Content Management Systems (CMS), Elasticsearch, Gmail API, Gmail, SDK Development, Software Engineering, Software Architecture, Android, OAuth 2, SecOps, Scalability, Process Development, Load Testing, Web Scalability, Google Ads, Google Tag Manager, Google Analytics 4, APIs, htaccess, SEO Tools, AngularJS, Accessibility, Monitoring, Data Warehousing, Observability Tools, JSON, XML, HL7, PuTTY, Apache Tomcat, Apache Ant, NetBeans, Python API, Big Data Architecture, Data Cleansing, Data Handling, Concurrency, Google Sheets, Google API, NGINX, Performance Tuning, Automated Testing, Testing, Middleware, MVC Frameworks, Spring, Large Scale Distributed Systems, Technical Writing, Large-scale Projects, Unix, API Connectors, PDF, Object-oriented Programming (OOP), JVM, Relational Database Services (RDS), Embedded C++, System Integration
Engineer
2005 - 2011
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.
Technologies: PHP, JavaScript, C++, Java, Algorithms, Linux, GNU Debugger (GDB), Boost, CMake, Artificial Intelligence (AI), GitHub, C, Back-end Development, Qt, Bots, Cloud Infrastructure, Full-stack Development, Reddit API, Perl, Content Management Systems (CMS), Elasticsearch, SDK Development, Software Engineering, Software Architecture, iOS, Android, Load Testing, Web Scalability, htaccess, Symfony, JavaFX, PyQt, Data Warehousing, Observability Tools, JSON, XML, Jakarta Server Pages (JSP), PuTTY, Apache Tomcat, Apache Ant, Apache Struts 2, NetBeans, Big Data Architecture, Data Cleansing, Performance Tuning, Automated Testing, Testing, Middleware, jQuery, Apache, MariaDB, Large Scale Distributed Systems, Visual Studio, XHTML, Large-scale Projects, Unix, Oracle, Microsoft Power Platform, Object-oriented Programming (OOP), Front-end, JVM, Embedded C++, SLAM, Simultaneous Localization & Mapping (SLAM), Apache ZooKeeper, Macros, Excel VBA, Excel Macros
Principal Engineer
2001 - 2005
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.
Technologies: C++, Java, JavaScript, Linux, GNU Debugger (GDB), Boost, GitHub, Back-end Development, Google Cloud, Integration, Load Testing, Low-level Programming, JavaFX, Jakarta Server Pages (JSP), Performance Tuning, SOC 2, Middleware, Large Scale Distributed Systems, Visual Studio, Hibernate, Unix, Oracle, Object-oriented Programming (OOP), JVM, Embedded C++, SLAM, Simultaneous Localization & Mapping (SLAM), Embedded Development, SnapLogic, System Integration, PeopleSoft, Salesforce, Visual Basic for Applications (VBA)
Experience
Uber | Global Service Platforms
Uber, the leading company in the ride-sharing and gig economy, is driven by the concept of movement. Movement fuels the organization and is an integral part of its identity. They are constantly innovating and improving how they facilitate transportation, enabling customers to reach their desired destinations, acquire the things they need, and provide earning opportunities in locations across the globe. They strive to deliver these services in real time.
I 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.
I worked as a tech leader for Uber Elevate, an aerospace effort of uber.
I 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.
I worked as a tech leader for Uber Elevate, an aerospace effort of uber.
Airbnb | Product and Service Infrastructure and Data Flow
http://www.airbnb.comAirbnb's vision is to create a world where anyone can belong anywhere they go. It is built around the idea that everyone deserves to experience the perfect trip, choosing their accommodations, activities, and connections. With this in mind, they empower millions globally to become entrepreneurs by utilizing their spaces, interests, and skills. This is the audacious and rewarding mission to which Airbnb's diverse team is dedicated.
I 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.
I 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.comGoogle's mission is to organize the vast amount of worldwide information and make it universally accessible and helpful. With billions of users in mind, they continuously strive to develop groundbreaking products and cutting-edge tools that shape the future.
I joined the project to combine the power of search and ads with AI technology, working on the ads UI and developing coupon ads.
I 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
Roblox reimagines how people come together by enabling individual connections and fostering meaningful relationships in the Meta world. Roblox employees tackle complex questions and drive incredible innovation.
I worked at Roblox as a tech lead, handling the architecture, development, and maintenance of their next-generation platform, which moved from a monolithic to a microservice architecture.
I worked at Roblox as a tech lead, handling the architecture, development, and maintenance of their next-generation platform, which moved from a monolithic to a microservice architecture.
Citrus Lane | Back-end Infrastructure, Website, and Apps
Citrus Lane is a startup providing children subscriptions. It serviced tens of thousands of children subscriptions and experienced a remarkable tenfold growth.
I joined them as a tech leader, leading the team to build the 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
Siebel, the leading global customer relationship management (CRM) company, specializes in building enterprise software solutions.
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.
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.comYahoo's media, technology, and business platforms connect hundreds of millions of people worldwide to the things they love. With apps and sites like Yahoo Sports, Yahoo Finance, Yahoo Fantasy, and Yahoo Mail and a powerful, open platform that connects brands and publishers to passionate fans, they're all about putting an exclamation point on what users are into.
I worked at Yahoo as a principal engineer and tech lead, contributing to multiple tasks regarding the platform, infrastructure, and cloud data storage systems.
I 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
I built a trading system that generated signals based on the owner's various algorithms and did the auto trading. It was built on top of ib_insync. The system provides a framework for owners to plug in algorithms.
Student Class Selection System
An internal web system that allows students to select available classes. I built it on top of MySQL and Ruby on Rails. It comes with an admin dashboard, and it enables 500 students to choose among 20 classes based on various criteria and capacities.
Finance, Legal, and Web Scrape Project
A whole system to scrape many finance and legal systems with special requirements. This also involved a website for crud, alert, display, user management, and real-time communication to end users massively and swiftly.
Trading Bots
A Python-based trading system for trading. I utilized IB trading APIs, pine script on trading views, and other technologies. This is a system built for a private team.
They could plug in the specific algorithms.
They could plug in the specific algorithms.
DMX Cat
I designed, built, deployed, and maintained high-quality iOS and Android apps for Bluetooth and hardware applications. I also developed Mac, Windows, and Linux applications, as well as hardware and firmware. Additionally, I used C++ and client-side technologies in my work.
Video Conference
As a senior engineer, I built a system to support a hardware-based video system from end to end. I worked on many aspects of the project, from the client side and app to the firmware, video algorithm, and protocol for the startup. I also maintained the product, firmware, and app.
Ice Diamond
Built and maintained one of the biggest online diamond stores backed by top VC. I worked on eCommerce platforms, CRM, data analytics, SEO, operations, etc. As a tech leader, I hired and mentored tech people, working with the PM and DevOps on all initiatives.
Electronic Accessory
Served as a tech leader and led a team to build and maintain a top-level electronic accessory website that ranked at the top of the US market. I focused on SEO, the eCommerce platform, the database, operations, PHP, analytics, apps, payment, and Google Ads.
DeFi Solana Smart Contract Web3
I completed a project on the Solana blockchain that leverages smart contract technology to create a decentralized finance (DeFi) platform. The project focuses on enabling users to engage in yield farming, staking, and liquidity provision, utilizing Solana's high throughput and low latency features.
One of the Largest Lawyer Sites
I created a comprehensive website and app tailored for lawyers and their clients, including a robust pipeline and API integration for data collection, extraction, presentation, and querying specifically for US lawyers. Additionally, I managed DevOps responsibilities to ensure seamless deployment and maintenance.
Healthcare Project
http://Allermetrix.comThe client is in the healthcare industry. They use two software programs—one called Clarion and the other involving PHP programming. They send results to hospitals and laboratories through secure servers but are currently experiencing issues with the interchanges and sending the results. They are currently working with a Clarion developer, but they need a developer who can support them with the PHP part.
Education
1998 - 2001
Master's Degree in Computer Science
The University of New Mexico - Albuquerque, New Mexico, USA
1993 - 1998
Bachelor's Degree in Computer Science
Tsinghua University - Beijing, China
Skills
Libraries/APIs
Node.js, Stripe, Stripe API, NumPy, React, Python API, Interactive Brokers API, TWS API, Reddit API, Rails Engines, Beautiful Soup, OpenAI Assistants API, Gmail API, Authorize.net, Office 365 API, REST APIs, Pandas, Google Sheets API, ZIO, Django ORM, PyQt, PySide, JSII, Crawlee, Puppeteer, OpenAI API, Google API, Solana.py, CheerioJS, Goutte, Python Asyncio, Asyncio, Google Maps, Google Maps SDK, Mapbox API, RxJava, jQuery, NCR API, PostgREST, Vue
Tools
Logging, Amazon Elastic Container Service (ECS), AWS Key Management Service (KMS), Terraform, HashiCorp, Cloud Dataflow, Git, GNU Debugger (GDB), CMake, GitHub, RabbitMQ, ChatGPT, Google Analytics, Docker Hub, BigQuery, Cron, Android Studio, Expo, Azure Active Directory B2C (ADB2C), Hashistack, Azure OpenAI Service, Amazon Simple Queue Service (SQS), Kafka Streams, Microsoft Power Apps, Zapier, RSpec, Java Development Kit (JDK), Amazon SageMaker, Observability Tools, FileZilla, PuTTY, Apache Tomcat, Apache Ant, IntelliJ IDEA, Google Sheets, NGINX, Azure Kubernetes Service (AKS), Azure Traffic Manager, GTK, Figma, MongoDB Atlas, Elastic, Apache, Visual Studio, Babel, Webpack, WildFly, Microsoft Power Pages, Microsoft Power BI, Apache ZooKeeper, Amazon Cognito, Auth0, Retool, Wix, SnapLogic, Microsoft Copilot, AspDotNetStorefront, Keycloak, Apache Beam, AWS IAM, CTools, Seos
Languages
Python, Go, Java, C++, Ruby, JavaScript, HTML, PHP, Rust, GraphQL, SQL, C#, TypeScript, CSS, C, Snowflake, Scala, Embedded C, Perl, Kotlin, Swift, SAML, Dart, XML, Google Apps Script, HTML5, Visual Basic, XHTML, Embedded C++, Solidity, Visual Basic for Applications (VBA), Excel VBA, Python 3, Pine Script
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, Blazor, Electron, Spring Boot, Symfony, AngularJS, Django REST Framework, Apache Spark, GStreamer, Jakarta Server Pages (JSP), Apache Struts 2, Flask, .NET MAUI, CakePHP, Spring, Redux, Hibernate, Vanilla JS, ASP.NET MVC, Razor, Angular
Paradigms
DevOps, Hosting, Microservices, ETL, API Architecture, Continuous Integration (CI), Search Engine Optimization (SEO), Business Intelligence (BI), Serverless Architecture, Cross-platform, Mobile Development, Load Testing, API Observability, HIPAA Compliance, Agile Software Development, Automation, Automated Testing, Testing, Object-oriented Programming (OOP), Microservices Architecture
Platforms
Linux, Apache Kafka, Docker, Kubernetes, Windows, WordPress, Amazon Web Services (AWS), Google Cloud Platform (GCP), Firebase, BigCommerce, DigitalOcean, Heroku, Mobile, iOS, Android, Mapbox, Azure, Google Ads, SharePoint, Algolia, HubSpot, MacOS, Amazon EC2, Solidus, JavaFX, Magento, Shopify, Databricks, Amazon, NetBeans, Zendesk, PagerDuty, Xamarin, Unix, Oracle, AWS Lambda, Microsoft Power Platform, Microsoft Power Automate, JVM, Embedded Linux, Toast (Point-of-sale Platform), Salesforce, Blockchain, Neto, Wand
Storage
MySQL, PostgreSQL, NoSQL, Redshift, Data Pipelines, Data Lakes, Cassandra, Redis, MongoDB, Google Cloud, Elasticsearch, Amazon DynamoDB, Amazon S3 (AWS S3), JSON, Alibaba Cloud, MariaDB, Datadog, Microsoft SQL Server, ClickHouse, Google Cloud Spanner
Industry Expertise
Project Management, Accounting, Trading Systems
Other
Software Development, Software, Full-stack, Web3, 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, Algorithmic Trading, Data Science, 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, Mobile App Development, Advisory, Leadership, Scalability, Technical Leadership, Startups, Coaching, Engineering, Process Development, Web Scalability, Google Tag Manager, Google Analytics 4, Office 365, PWA, Progressive Web Applications (PWAs), Gemini API, DNS, htaccess, GoDaddy, SEO Tools, Hardware, Firmware, Low-level Programming, USB, MDM, Jamf, Mobile Device Management (MDM), Fintech, Profiling, Embedded Rust, Embedded Systems, Internet of Things (IoT), Accessibility, Monitoring, Machine Learning Operations (MLOps), OpenTelemetry, Data Warehousing, Prometheus, Website Data Scraping, Solana, Smart Contracts, Crypto, Containers, Stable Diffusion, Marketing Technology (MarTech), ElevenLabs Solutions, Chatbots, Live Chat, eBay, HL7, Trading Bots, Big Data, Big Data Architecture, Data Cleansing, Data Handling, Concurrency, Generative Artificial Intelligence (GenAI), Containerization, Embedded Software, Decentralized Finance (DeFi), Finance, Equities, Equity Trading, Hedge Funds, Options Trading, Profit & Loss (P&L), Stock Market, Stock Exchange, Trade Finance, Fund Management, Tickers, Stock Trading, FastAPI, Performance Tuning, WebSockets, Time Series Modeling, Image Generation, SOC 2, Mapbox SDK, Middleware, Jetpack Compose, Quantitative Analysis, Quantitative Finance, MVC Frameworks, Quarkus, Large Scale Distributed Systems, Single Sign-on (SSO), Technical Architecture, Technical Writing, Mobile Apps, Large-scale Projects, Social Security, IDP, API Connectors, Cloud Architecture, Airtable, PDF, Front-end, Team Leadership, Relational Database Services (RDS), SLAM, Simultaneous Localization & Mapping (SLAM), Embedded Development, TouchGFX, Point of Sale, Clover POS, Lightspeed, Revel POS, Square Payment Gateway, Natural Language Processing (NLP), Speech Recognition, Security, Games, Sports, Multi-factor Authentication (MFA), SSH, System Integration, PeopleSoft, Workflow Automation, FTP, IIS, Third-party APIs, Macros, Excel Macros, Robotic Process Automation (RPA), Dynamic Load Balancing, Plugins, PKI, LangChain, DDS, PDF Scraping, Midjourney, Strapi, Analysis, Dashboards, AI Website Builders, Buffer Management, ExpressIF, Bluetooth, ESP32, ACH Payments, Google, PayPal, Payment APIs
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