Daniel Lin

- 2021/8 KKStream - Senior Backend Engineer
I focus on solving problems rapidly and integrating services in multiple product teams.
- Platform Service: Inducting the microservice framework and the software architecture. By leveraging the solution to the integration between application and infrastructure from the community, we could build robust microservice rapidly.
- Loom:
- Developing the backend of encoding CMS API
- Golang, AKS, and KEDA
- Moment: Building credit, payment, invoice function.
- Golang, ECS / Lambda / SQS
- Kaleido:
- Microservice redesign:
- mitigate unnecessary development costs by reducing communication overhead
- Golang, EKS, Git Ops using ArgoCD

The product is in the stage of moving from monolithic architecture to microservice architecture. The best concurrency number in actual ticket selling events grew up to 300 thousand users online when I was there.
- Optimizing Performance
- Using Prometheus / ELK Finding performance issue.
- Using PGHero monitoring slow query and database performance
- Using flame graph to find the bottleneck, reducing 50% latency of verifying tickets process in the significant event.
- Reducing failure payment by migrating to the asynchronous transaction.
- Stress Testing
- Scaling a large number of robots, an internal tool using Terraform on GCP and Selenium and Redis distributed stress testing platform, on VMs to simulate real traffic from Taiwan to Tokyo.
- Backend Ruby on Rails / Golang
- Payment integration: Adyen, Newebpay, Apple Pay, Google Pay
- Credit system integration in a tremendous amount of traffic requirement
- Random captcha to block robots
- SMS verification
- Upgrade Ruby on Rails 4.2 to 5.2
- SRE / Dev Ops:
- Building Jenkins CI/CD pipeline
- Building logging pipeline
- Bumping version of Elastic Search from 1.7 to 5.X. Redesign index config and search query generation logic.
- Training Process:
- Using pair programming and TDD to speed up engineer onboarding.
- Sharing technique actively in team weekly.