About

Younsung Lee

DevOps Engineer. Github.

Work Experience

DevOps Engineer | Coinone
May 30, 2023 ― Present (1 yr 6 mo)

AWS, GCP, Kubernetes, Observability, CI/CD, Terraform, Infrastructure Ops

• Manage and operate 6 EKS clusters in a multi-stage environment: experienced EKS versions v1.24 to v1.27.
• Migrate EKS node groups provisioned with terraform from AL2 to AL2023.
• Operate Kubernetes policy engine ^Kyverno and Node Termination Handler. * **
• Improve scalability by applying pod autoscaling based on Throughput Per Seconds metric using KEDA in the production environment. *
• Automate repetitive operational tasks.
• Operate CI/CD pipeline based on Github Actions Workflow and ArgoCD.
• Build and operate RabbitMQ, MSK Cluster and OpenSearch Cluster. * **
• Build and operate Github Enterprise Server, Github Enterprise backup utilities and Actions Runner Controller. * **
• Containerize github enterprise backup server and migrate workload from EC2 to kubernetes cronJob for leveraging dedicated EKS cluster.
• Develop and release backup-utils helm chart as a maintainer. *
• Provision and operate multi-account AWS infrastructure using terraform modules.
• Integrate private networking between GCP and AWS to connect GCP Service APIs from EKS Pods.
• Implemented and managed Velero server in a production EKS cluster, orchestrating scheduled backups and executing recovery tests. *
• Automate daily resource creation using GitHub Actions for terraform apply, and enhance Terraform workflows with Atlantis for collaboration. *
• Deployed and managed Linkerd, a service mesh, to enhance cluster security with mTLS and improve observability between microservices.

DevOps Engineer | Greenlabs Financial
Sep 5, 2022 ― Apr 7, 2023 (7 mos)

AWS, Kubernetes, Istio, Observability, CI/CD, Terraform, MLOps, Infrastructure Ops

• Acquired electronic finance business license #2022-483 after building multi-account AWS infrastructure for 3 months from September to December 2022. *
• Managed and operated 2 EKS clusters in a multi-stage environment: experienced EKS versions v1.24 to v1.25. *
• Provisioned and operated multi-stage AWS infrastructure using terraform.
• Optimized multi-account infrastructure and reduced monthly AWS cost from $6800 to $4800, 30% monthly cost savings from Jan 2023 to Mar 2023.

Cloud Engineer | Watcha
Feb 14, 2022 ― Aug 5, 2022 (6 mos)

AWS, Kubernetes, CI/CD, Terraform, Infrastructure Ops

System Engineer | KDN
Dec 16, 2013 ― Feb 11, 2022 (8 yrs 2 mos)

On-premise, Linux administration, VMware Cluster administration, Storage administration, Backup and Recovery, Monitoring, Infrastructure Ops

• Orchestrated the uninterrupted operation of VMware cluster environments, guaranteeing stability and high availability.
• Automated routine operational tasks using python and bash script.
• Collaborated closely with the development team to understand their virtual machine provisioning needs.
• Provided technical support for virtualization-related incidents and challenges, consistently ensuring prompt issue resolution.
• Collaborated with vendors to address hardware and software issues, resulting in minimal disruptions to operations.
• Installed and configured backup agents for VMs, executing OS and database-level backup and recovery procedures using EMC Networker.
• Out of job due to military service, ROKAF from Nov 2014 to Nov 2016.

Education

BSE, ICT Applied | Chosun University
Mar 2018 ― Feb 2022

Certification