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© 2026 Yosef Adi Sulistyo
Yosef Adi Sulistyo
Expertise & Tooling
Skills & Technologies
Infrastructure
Cloud Platforms
DevSecOps & IaC
Networking
Programming & Databases
Monitoring & Observability
Professional Experience
Work History
DevSecOps Engineer Lead
Sep 2024 – PresentPT Synapsis Sinergi Digital
Leading the DevSecOps team in architecting and maintaining hybrid-cloud and on-premise infrastructure for production-grade environments.
- Designed HCI-based IT infrastructure using Proxmox VE and Ceph Distributed Storage.
- Designed and provisioned end-to-end GCP infrastructure using OpenTofu + Terragrunt: multi-VPC topology (Database, App, Ingress-Egress VPCs with bidirectional peering), multi-cluster GKE (app, db, dms) with private nodes, Workload Identity, Shielded Nodes, Managed Prometheus; GCE instances (NAT gateway, GitLab Runner, FleetDM, Flipt); Cloud SQL; Google KMS for Vault auto-unseal; Cloud NAT; Cloud IAP for zero-public-IP SSH; and site-to-site VPN to on-premise.
- Implemented company-wide SSO using Microsoft Entra ID.
- Evaluated Oracle Cloud, AliCloud, and Huawei Cloud for client digital transformation projects.
- Defined and led team implementation of SDN across company infrastructure.
- Reduced operational costs by migrating dev infrastructure from cloud VMs to bare-metal Kubernetes and transitioning from IPv4 to IPv6 with Cloud NAT (NAT64/NAT44).
- Developed internal tooling in Go and Python to optimize CI/CD pipelines and resolve infrastructure issues.
- Built customized OCI container base images, reducing image size and improving security posture.
- Defined KPIs, SOPs, and business processes for the DevSecOps team.
DevSecOps Engineer
May 2023 – Aug 2024PT Synapsis Sinergi Digital
Led team GitOps implementation and migrated infrastructure from public cloud to colocated bare-metal to reduce operational costs.
- Led DevSecOps team in implementing GitOps principles using Ansible, Semaphore, ArgoCD, and GitLab CI.
- Migrated infrastructure from public cloud VM instances to colocated bare-metal servers via Proxmox VE.
- Proposed and deployed production infrastructure on AWS (EKS, EC2 ARM, S3, RDS/PostgreSQL) in ap-southeast-1, optimizing cost-to-performance with ARM-based CPUs.
- Maintained self-managed Kubernetes clusters for production deployments.
DevOps / Site Reliability Engineer
Dec 2022 – Apr 2023PT Synapsis Sinergi Digital
Built CI/CD pipelines with integrated security scanning, deployed Kubernetes clusters, and established monitoring and security infrastructure.
- Built CI/CD pipelines using GitLab CI with integrated vulnerability scanning (Grype) and automated release tagging.
- Deployed and managed unmanaged Kubernetes clusters with Traefik Ingress Controller and ArgoCD.
- Configured Loki + Grafana monitoring stack for a Golang (GoFiber) backend.
- Set up Proxmox VE for bare-metal servers and configured NAT networking for VPS workloads.
- Integrated HashiCorp Vault for secrets management; set up a multiprotocol VPN server.
- Implemented an Intrusion Prevention System (IPS) using CrowdSec.
- Conducted load testing with k6 to size Kubernetes production cluster nodes.
Education & Certifications
Background
Education
Bachelor of Electrical Engineering
Universitas Gadjah Mada (UGM)
Sep 2020 – Jul 2024
GPA: 3.72 / 4.00. Focused on embedded systems and computer networks.
Math and Science
SMA Negeri 3 Yogyakarta
2017 – 2020
Certifications
Featured work
Recent Projects
Selected work from the portfolio.
GCP Multi-Cloud Infrastructure with OpenTofu + Terragrunt
Infrastructure Architecture + IaC
End-to-end GCP infrastructure provisioning using OpenTofu and Terragrunt — multi-VPC topology, multi-cluster GKE, Workload Identity, site-to-site VPN, and zero-public-IP access via Cloud IAP.
January 1, 2025
View projectBare-Metal HCI & GitOps Platform
Infrastructure + DevSecOps
Hyper-Converged Infrastructure built on Proxmox VE and Ceph, running self-managed Kubernetes clusters with GitOps delivery via ArgoCD — replacing costly cloud VMs while maintaining production-grade reliability.
January 1, 2024
View projectLatest writing
From the Blog
Recent articles and notes.
GitOps with ArgoCD on Self-Managed Kubernetes
3 min read
A practical account of adopting GitOps principles on bare-metal Kubernetes using ArgoCD, GitLab CI, and Ansible — and why the discipline matters more than the tooling.
April 10, 2026
Read articleIPv6-First Infrastructure with NAT64/NAT44 on GCP
2 min read
How switching from IPv4 subscriptions to an IPv6-native model with Cloud NAT (NAT64/NAT44) cut infrastructure costs and simplified the network — without breaking IPv4 reachability.
April 1, 2026
Read articleLet's build something together.
Reach out for project inquiries, technical collaborations, or just a coffee chat.