GitOps by default
Cluster infra and tenant workloads reconciled from Git — fully auditable, no snowflakes.
Senior DevOps / Container Platform Engineer · eu-central-1 /
Elmshorn
KEVIN SIEMERS
The operating principle behind a global container platform: if it isn't in Git, it isn't in the cluster. OpenShift, EKS, Kyverno at the gate.
status
open to opportunities
region
eu-central-1 · Elmshorn
since
2014 · 12y+ uptime
local
00:00:00
Container Platform Engineering
Kubernetes
Red Hat OpenShift
OKD
Amazon EKS
Karpenter
Fargate
Docker
Podman
Helm
Harbor
ArgoCD
GitOps
Kyverno
NetworkPolicies
Terraform
Terragrunt
Ansible
AWX
SaltStack
Tekton
GitLab CI
OpenShift BuildConfigs
Prometheus
Grafana
Grafana Alloy
Mimir
Loki
CloudWatch
Nagios
PostgreSQL HA
pgpool-II
PITR
NetApp Trident
Pure Portworx
VMware vSphere
AWS EKS
AWS EC2
AWS IAM
Python
Bash
Docs-as-Code
AsciiDoc
Antora
Disaster Recovery
SRE
ITIL v3
24/7 on-call
01 — whoami
GitOps isn't a tool.
GitOps isn't a tool.
It's the contract.
Twelve years operating platforms other teams bet their business on: clusters that heal themselves, tenants that self-service safely.
I build and run multi-tenant Kubernetes and OpenShift platforms across on-prem and AWS — ArgoCD for delivery, Kyverno for guardrails, Prometheus + Grafana + Alloy + Mimir + Loki for the truth, and a disaster-recovery plan that's been validated, not just written.
The throughline: automate the toil, secure by default, and advise the teams building on top.
Guardrails as code
Kyverno policies and NetworkPolicies over runbooks. Compliance baked into the delivery path.
Advise, operate, mentor
Consult tenant teams on OpenShift/EKS patterns, own on-call, still ship the automation myself.
02 — git log --career
Deployment history.
release/2020.04 — HEAD
Kühne+Nagel
Apr 2020 → present
Container Platform Engineer — Hybrid Cloud (OpenShift + AWS EKS) now
Operate the global Red Hat OpenShift multi-tenant platform for EMEA and the Americas — two production clusters with 500+ tenant namespaces and 10,000+ running pods, plus a dedicated infra cluster (Harbor, ArgoCD, observability), in a 4–5 person team. GitOps everything with ArgoCD, enforce multi-tenant guardrails via Kyverno policy-as-code, and design CI/CD with Tekton, GitLab CI, and BuildConfigs. Built the EKS platform layer on top: Terraform + ArgoCD + Helm, Karpenter and Fargate for scale/cost, unified observability on CloudWatch + Grafana Alloy + Mimir + Loki. Own DR planning and Docs-as-Code (AsciiDoc + Antora).
Red Hat OpenShift
Amazon EKS
ArgoCD · GitOps
Kyverno
Terraform
Ansible / AWX
Karpenter · Fargate
Prometheus · Grafana
Alloy · Mimir · Loki
Harbor
Antora · AsciiDoc
Disaster Recovery
branch/education
FOM University, Hamburg
Oct 2018 → Feb 2022 · part-time
B. Sc. Business Informatics (Wirtschaftsinformatik)
Bachelor's degree completed in parallel to full-time employment at K+N. Final grade 1.2 · Thesis 1.0 — a practical, cost-efficient PostgreSQL HA architecture compared to Oracle, applied at K+N.
release/2014.07
Kühne+Nagel
Jul 2014 → Mar 2020 · 5y 9m
DevOps System Engineer — Open Source Platform & Automation
Operated 500+ CentOS VMs across two geographically separated VMware vSphere data centres for every EMEA business unit — Contract Logistics, Road, Air, Sea Freight — managed via SaltStack and later Ansible, with Nagios monitoring and self-healing automations. Specialised in PostgreSQL HA (pgpool-II, STONITH failover, PITR) and delivered DBMOTO iSeries-to-Postgres replication + Pentaho ETL powering dashboards for Amazon, Beiersdorf, PepsiCo, Yamaha, Philip Morris, and Weber. Flagship: rolled out CLIP on-site at the Amazon Naugatuck, CT data centre.
PostgreSQL HA
pgpool-II
SaltStack
Ansible
VMware vSphere
Nagios
DBMOTO
Pentaho ETL
Python · Bash
24/7 on-call
02a — git diff --stat
12y+
Years in enterprise delivery
500+
Tenant namespaces operated
10K+
Running pods across two clusters
2
Continents served (EMEA + Americas)
Twelve years, diffed.
Twelve years of commits, squashed into numbers.
03 — cat stack.yaml
The toolchain, declared.
production toolkit
Twelve years compounding across on-prem Kubernetes/OpenShift, hybrid-cloud EKS, PostgreSQL HA, and Docs-as-Code — the stack a global tenant platform is built on.
1stack:2 cloud: [aws, on-prem]3 orchestration: [openshift, kubernetes, eks, karpenter, fargate]4 delivery: [argocd, gitlab-ci, tekton, buildconfigs]5 iac: [terraform, terragrunt, ansible, awx, saltstack]6 policy: [kyverno, networkpolicies]7 observability: [prometheus, grafana, alloy, mimir, loki, cloudwatch]8 data: [postgresql-ha, pgpool-ii, dbmoto]9 storage: [netapp-trident, pure-portworx]10 docs: [asciidoc, antora, docs-as-code]
ArgoCD, GitLab CI, Tekton, OpenShift BuildConfigs, Terraform, Ansible/AWX, SaltStack
Red Hat OpenShift, Kubernetes, Amazon EKS, Karpenter, Fargate, Helm, Harbor
Prometheus, Grafana, Alloy, Mimir, Loki, CloudWatch, Kyverno, NetworkPolicies
04 — ls -la credentials/
Proof, not promises.
AXELOS
ITIL v3 Foundation
—
education
B. Sc. Business Informatics (Wirtschaftsinformatik)
Final grade 1.2 · Thesis 1.0 — PostgreSQL HA vs Oracle
FOM University of Applied Sciences, Hamburg
Fachinformatiker für Systemintegration
Dual Vocational Program (IT Specialist for Systems Integration)
Kühne+Nagel, Hamburg · Berufliche Schule ITECH Elbinsel Wilhelmsburg (BS14)