# Haojun Y.

> Java Developer at Fortinet

Location: Mountain View, California, United States
Profile: https://flows.cv/haojun

•	Experienced Java Developer with 8 years of experience in Core Java, Spring, Java Multithreading development, Databases (Both RDBMS and Non-RDBMS), Caching and Messaging, with exposure to Python and Front-End development.
•	Designed and developed different architectures like Spring MVC, Event and Message Driven Microservices. Achieved with high throughput and fault-tolerance using caching, parallel system.
•	Experienced in Agile development. Leaded project by gathering requirements, designing architecture and data scheme, and coordinating tasks with team members. 
•	Worked on Front-End and Python Development. Keep Learning new technologies like Front End Development, Python, Django, Scrappy, Data Mining.

## Work Experience
### Senior Software Engineer @ Fortinet
Jan 2018 – Present | Sunnyvale, California, United States
•	Designed and built chaining asynchronous task system with high fault tolerant and scalability. Developed task coordinator using Java Concurrency and Spring AOP to manage task pools, dispatch tasks via SQS or Kafka and monitor workers’ results with 100 - 200 QPS.
•	Designed and built workers as micro services using Spring Boot to pull and process clients’ metadata from multiple cloud services. Store user data and context in Postgres and Elastic Search.
•	Lead projects, communicated with stakeholders, designed architecture, code reviews, and coordinated tasks by following Scrum methodology. Responsible for team member onboarding and interviews.
•	Setup test framework using JUnit and Mockito for automated unit and integration testing. 
•	Implemented OAuth2 Service to integrated with company single sign on service. Published existing APIs using Swagger.
•	Developed Rest APIs. Setup Jenkins, Kubernetes to deploy dockers on to AWS ECS for CI/CD. Solved performance issues by analyzing jmap and jstack.

### Java Developer @ MiMedia
Jan 2016 – Jan 2017 | Brooklyn, NY
•	Developed Rest APIs on the platform and internal management involving MySQL.
•	Delivered an internal management web app using CoffeeScript, React, Bower, Node.js, and NPM.
•	Involved in implementing a multi-agent based, distributed platform using Jade for handling tasks to workers. It provides better transparency, scalability, and performance.
•	Developed User Analytics Service to store client’s analytics data using Spring AMQP framework and RabbitMQ messaging. Develop Android SDK for Android team to connect to our Analytics Proxy.
•	Implemented object storage using Swift and AWS. Experienced in OpenStack and docker to quickly add a new instance.

### Java Developer @ Freddie Mac
Jan 2014 – Jan 2016 | McLean, VA
•	Interacted with business users for understanding and analyzing the requirements.
•	Remediated JDBC in persistence layer and named queries to use SQL Server as the database. 
•	Involved in migrating Shell scripts to use SQL Server as the database that executed by nightly batches. 
•	Involved in Migrating Sybase stored procedures and triggers to SQL Server.

### Java Developer Contract @ Hewlett Packard Enterprise
Jan 2013 – Jan 2014 | Trenton, NJ
•	Designed and Implemented Backend Services in Spring MVC and Oracle DB for New Jersey Motor Vehicle Automated Transaction System (MATRX).


## Education
### Master’s Degree in Computer Engineering
Rutgers University
Jan 2011 – Jan 2013

### Bachelor’s Degree in Electrical and Electronics Engineering
Harbin Engineering University
Jan 2006 – Jan 2010


## Contact & Social
- LinkedIn: https://linkedin.com/in/haojun-yin

---
Source: https://flows.cv/haojun
JSON Resume: https://flows.cv/haojun/resume.json
Last updated: 2026-03-22