Hao is available for hire
Hire HaoHao Yang
Verified Expert in Engineering
Back-end Developer
Chengdu, Sichuan, China
Toptal member since August 31, 2022
Bio
Hao is a back-end engineer with over six years of experience. He has worked as a developer, DevOps, and tech leader. He is familiar with the Java stack, DevOps, and agile methodologies. He likes to use best practices like TDD, pair programming, and others, to make development efficient and produce clean and maintainable code. Hao has a successful track record of collaborating with numerous Fortune Global 500 clients, assisting them in developing applications that cater to millions of users.
Portfolio
M2 Communications
Java, Java 17, Spring Boot, Redis, Google Cloud Platform (GCP), Elasticsearch...
ThoughtWorks
DevOps, Java, Kotlin, MongoDB, GitHub, Agile, Docker, Jenkins, CI/CD Pipelines...
ThoughtWorks
Kotlin, Java, Spring Boot, Video Streaming, Amazon Web Services (AWS), Agile...
Experience
Availability
Full-time
Preferred Environment
Agile, Java, Kotlin, Spring Boot, DevOps, Microservices, Amazon Web Services (AWS), Kubernetes, Docker, Jira
The most amazing...
...thing I've led and built is an open-source project to measure development performance based on Google's four key metrics theory. It has 300+ stars on GitHub.
Work Experience
Senior Developer
2023 - 2023
M2 Communications
- Acted as a senior software engineer, participated in developing a cryptocurrency exchange platform, and helped transform the monolithic application to a microservices architecture. The product is online now.
- Implemented a robust verification process for CAPTCHA generation and validation, ensuring the security and integrity of transactions on the platform.
- Built a notification service from scratch by myself, which could send emails and SMS, and it was used by many other services.
- Collaborated effectively within a fully remote team, communicated frequently with team members, and successfully met tight deadlines.
Technologies: Java, Java 17, Spring Boot, Redis, Google Cloud Platform (GCP), Elasticsearch, Large Scale Distributed Systems, Microservices Architecture, Object-oriented Programming (OOP), JVM, Front-end
Tech Leader
2022 - 2023
ThoughtWorks
- Collaborated with a leading Australian streaming company, successfully split the monolithic application into microservices, and provided APIs for the front end to render the pages. This project serves millions of users.
- Acted as the tech leader, focused on coding, solution design, and requirement analysis.
- Used Spring WebFlux as the framework for this project, and most of the team members didn't have experience. To solve this, I utilized sessions and code reviews to help the team members get on board quickly.
- Promoted best practices like pair programming, test-driven, and trunk-based development to help the team transfer knowledge more frequently and improve efficiency.
Technologies: DevOps, Java, Kotlin, MongoDB, GitHub, Agile, Docker, Jenkins, CI/CD Pipelines, Amazon Web Services (AWS), Jira, Spring Boot, Spring Data, NoSQL, REST APIs, Apache Maven, JPA, PostgreSQL, Back-end, Back-end Development, ETL, Git, Key Performance Metrics, Metrics, Technical Leadership, Static Analysis, Architecture, Google Cloud Platform (GCP), Event-driven Architecture, SQL Server 7, Spring Microservice, Elasticsearch, SaaS, Linux, Large Scale Distributed Systems, Microservices Architecture, Object-oriented Programming (OOP), JVM, Front-end
Tech Leader
2021 - 2022
ThoughtWorks
- Built an application based on Google's four key metrics theory. It integrates with CI/CD pipelines and uses the data to calculate metrics, which help teams measure development performance and identify improvement areas. It has 300+ stars on GitHub.
- Acted as the tech leader, focusing on solution design, coding, and maintaining the codebase after it was open-sourced.
- Analyzed the data from CI/CD pipelines and designed the algorithm for each metric calculation.
- Designed a solution that separates the calculation and integration logic; it makes the integration easy and won't impact the calculation logic. The app needed to integrate with various pipelines.
- Communicated with other teams to integrate our product and gathered valuable feedback. This feedback was analyzed and implemented, improving the project.
- Encouraged the team to use test-driven development (TDD) in this project; in the end, the unit test coverage was more than 90%.
Technologies: Kotlin, Java, Spring Boot, Video Streaming, Amazon Web Services (AWS), Agile, DevOps, Test-driven Development (TDD), Pair Programming, Redis, WebFlux, Gradle, Kubernetes, Docker, Jenkins, JSON Web Tokens (JWT), REST APIs, REST, Microservices, RabbitMQ, Real-time Streaming, Amazon Kinesis, Back-end, Back-end Development, Git, ETL, Distributed Systems, Terraform, Google Cloud Platform (GCP), Elasticsearch, SaaS, Linux, Large Scale Distributed Systems, Microservices Architecture, Object-oriented Programming (OOP), JVM, Front-end
Senior Developer
2018 - 2022
ThoughtWorks
- Worked with a world-leading mining group and created products such as a mining site visualization system, a blast notification system, and an equipment utility analysis system. These systems served 1,000+ users, improving site efficiency and safety.
- Acted as the key back-end developer and DevOps, focused on back-end coding, solution design, infrastructure setup, and maintenance.
- Took on most of the responsibilities in the back end, as a back-end engineer, which included writing most of the code (6+ services) and troubleshooting. I once successfully completed the backend development under a tight two-week deadline.
- Charged with the code quality. For example, I used TDD during the development, and the unit test coverage was more than 95%.
- Helped the team set up infrastructures like a CI/CD pipeline and Kafka and maintained the Kubernetes cluster. I've also implemented a solution for crossing AWS accounts and Kubernetes cluster deployment, which was used by many other teams.
Technologies: Java, Kotlin, Agile, Amazon Web Services (AWS), Amazon EC2, Docker, Pair Programming, Jira, Spring, Spring Boot, Jenkins, DevOps, GitLab CI/CD, Microservices, REST APIs, REST, API Integration, Apache Maven, JPA, PostgreSQL, Back-end, Back-end Development, React, JavaScript, Git, Distributed Systems, Architecture, Elasticsearch, SaaS, Data Engineering, Linux, Large Scale Distributed Systems, Microservices Architecture, Object-oriented Programming (OOP), JVM, Front-end, Angular
Senior Developer
2017 - 2018
ThoughtWorks
- Collaborated with a leading insurance company to build an online insurance claim system and an online insurance purchasing platform.
- Designed and implemented an SMS verification flow, which sends an SMS to the user, and the user can only do further operations after they verify the code. It integrated with the Redis and guarded the safety of the application.
- Helped onboard and train three junior developers for six months, helping them identify areas of weakness in their skill set and develop study plans. All of them passed probation periods successfully.
Technologies: Java, Agile, DevOps, Kotlin, Amazon Web Services (AWS), Test-driven Development (TDD), Pair Programming, MongoDB, MySQL, Jira, Python, Gradle, Apache Kafka, Spring, GraphQL, Redis, Amazon DynamoDB, Serverless, Kubernetes, Docker, CI/CD Pipelines, Jenkins, JSON Web Tokens (JWT), Microservices, Spring Boot, REST APIs, SQL, NoSQL, API Integration, APIs, Amazon Simple Notification Service (SNS), REST, PostgreSQL, Apache Maven, JPA, Amazon Kinesis, Real-time Streaming, Back-end, Back-end Development, React, JavaScript, Distributed Systems, Git, Terraform, Linux, Large Scale Distributed Systems, Microservices Architecture, Object-oriented Programming (OOP), JVM, Front-end, Angular
Back-end Developer
2017 - 2017
Tencent
- Developed an application to help staff record working hours. The whole department of 100+ people used the app.
- Helped new team members in onboarding and interviewed employees with different roles to analyze requirements.
- Learned C# and web development in three months with no previous experience.
Technologies: MySQL, SQL, Back-end Development, Object-oriented Programming (OOP), Front-end
Experience
Four Key Metrics Calculator
https://github.com/thoughtworks/metrikThis software development performance measurement tool is based on Google's four key metrics theory. It integrates with different kinds of CI/CD pipelines, like Jenkins and GitHub Actions, and uses the pipeline data to calculate the four key metrics. I was the tech leader of this project, responsible for solution design and back-end coding. This tool has been open-sourced.
Mining Site Visualization Tool
A mining website visualization tool to display the website information like stuff location, equipment location, blast holes, blast radius, etc. It helps the website supervisor know the information easily and improves efficiency and safety. This project has won an internal prize for innovation.
As a key back-end developer and DevOps, I developed a series of microservices and ETL and helped the team build and maintain infrastructures like CI/CD pipelines and Kubernetes cluster. In this project, we encouraged the team to try new technologies like Kotlin, GraphQL, and Kafka, helping the team develop an atmosphere of technology fanaticism and sharing.
As a key back-end developer and DevOps, I developed a series of microservices and ETL and helped the team build and maintain infrastructures like CI/CD pipelines and Kubernetes cluster. In this project, we encouraged the team to try new technologies like Kotlin, GraphQL, and Kafka, helping the team develop an atmosphere of technology fanaticism and sharing.
An Australian Leading Streaming Platform
An Australian leading streaming platform that serves millions of users. The application was monolithic; we helped split it into microservices and provided APIs for the front end to render the pages. I was the senior back-end developer and co-tech leader, focused on coding, solution design, and requirement analysis. In this project, I promoted practices like pair programming, test-driven development, and trunk-based development to help the team transfer knowledge and improve efficiency.
Education
2013 - 2017
Bachelor's Degree in Computer Science
Southwest Minzu University - Chengdu, China
Certifications
AUGUST 2020 - AUGUST 2023
AWS Certified Solutions Architect Associate
AWS
Skills
Libraries/APIs
REST APIs, React
Tools
Apache Maven, Gradle, Jenkins, Jira, GitHub, Amazon Simple Notification Service (SNS), GitLab CI/CD, RabbitMQ, Git, Terraform
Languages
Java, Kotlin, SQL, Python, GraphQL, JavaScript
Frameworks
Spring Boot, WebFlux, Spring, JSON Web Tokens (JWT), JPA, Spring Microservice, Angular
Paradigms
Agile, DevOps, Test-driven Development (TDD), Pair Programming, Microservices, Microservices Architecture, Object-oriented Programming (OOP), REST, Unit Testing, ETL, Key Performance Metrics, Event-driven Architecture
Platforms
Amazon Web Services (AWS), Apache Kafka, Kubernetes, Docker, JVM, Amazon EC2, Google Cloud Platform (GCP), Linux
Storage
Amazon DynamoDB, PostgreSQL, NoSQL, MySQL, MongoDB, Redis, Spring Data, SQL Server 7, Elasticsearch
Other
CI/CD Pipelines, Serverless, Back-end Development, Large Scale Distributed Systems, Solution Design, GitHub Actions, Team Leadership, API Integration, APIs, Video Streaming, Infrastructure as Code (IaC), Real-time Streaming, Amazon Kinesis, Back-end, Distributed Systems, Metrics, Technical Leadership, Static Analysis, Architecture, Java 17, SaaS, Data Engineering, Front-end
Collaboration That Works
How to Work with Toptal
Toptal matches you directly with global industry experts from our network in hours—not weeks or months.
1
Share your needs
Discuss your requirements and refine your scope in a call with a Toptal domain expert.
2
Choose your talent
Get a short list of expertly matched talent within 24 hours to review, interview, and choose from.
3
Start your risk-free talent trial
Work with your chosen talent on a trial basis for up to two weeks. Pay only if you decide to hire them.
Top talent is in high demand.
Start hiring