I was responsible for improving our web products to meet market demands quickly and efficiently. This included making the web pages load faster, improving the speed of backend processes, enhancing the user interface and experience, and implementing new features. Since we're operating an entertainment product, fast response toward users' likes and making our product load as fast as possible is critical. I mainly used C# (.NET, .NET Core) and JavaScript (Vue.js), along with some basic knowledge of TypeScript. Additionally, I could package source code into microservices using Docker and deploy them using Kubernetes. I also designed and optimized database schemas and queries, using tools to debug, modify, and improve query performance. I can manage multiple projects using Git to build and optimize Continuous Integration/Continuous Deployment (CI/CD) pipelines from scratch, reducing deployment time and human error risk during deployment. Furthermore, I focused on creating unit tests to express scenario requirements, improving code readability and maintainability. I promoted agile development practices, leading team planning, review, and retrospective meetings to collaboratively set team goals and learning objectives.