..
Projects
Freelance
since 10.2022
GitOps for multi-dimensional software deployments
LYNQTECH GmbH, SaaS sales processes for energy suppliers, Germany, remote and on-site | since 10.2022
- Micro-service architecture on Kubernetes on AWS; multiple clients with multiple environments each
- Transformation of existing cloud infrastructure and software stack towards GitOps approach based on FluxCD and TF-Controller
- Design and implementation of AzureAD as central Authentication and Authorization provider for Kubernetes landscape
- 100+ micro-services, 10 developer teams, 3 environments per client
- Technology used: AWS, Azure, Kubernetes, FluxCD, Terraform Controller, Helm, Github Actions, DroneCI
I gave a talk about the project and the challenges of running Terraform at scale in GitOps style. Read more
Security review of a collaboration platform
Platform for structured interview processes, Germany | 12.2023
- Review of AWS public cloud setup
- Authentication, authorization, permission system
- Analysis of user and software flows, attack targets and vectors
- Analysis of business resilience, desaster recovery
- Technology used: AWS, Lambda, IAM, Cognito, AWS CDK
Enablement of end-to-end observability based on Datadog
Platform for energetic building reviews, Germany, remote | 11.2023
- introduction of Real User Monitoring (RUM)
- enablement of Datadog Agent for backend
- enablement of SLO from customer perspective
- Technology used: Datadog, Typescript, AWS
Bootstrapping AWS cloud environment
Startup for financial audits, Germany, remote | 10.2022 – 04.2023
- Microservice architecture on Elastic Container Service on AWS
- Bootstrapping of infrastructure; development and deployment processes
- Microsoft Azure as Identity Provider
- Technology used: AWS, ECS, Cloudformation, Github Actions, Azure, Golang
TIER Mobility SE
Micro Mobility Startup Berlin | 12.2018 - 10.2022
Green field AWS public cloud setup for micro-services, scaled from 3 persons to 20 staff in 3 teams, serving ~250 developers and supported the business in 560+ cities and communities in 33 countries with a fleet of more than 300,000 vehicles (09/2022 Source)
Read more at the TIER Engineering blog: https://tier.engineering/
Cloud infrastructure as a product
- Multi cluster, multi environment execution platform based on EKS and Istio as service mesh
- Internal developer platform based on terraform, opinionated modules and spacelift.io
- Separated into multiple global products cooperatively handled by regional teams
- Read more
- Technology used: Spacelift.io, Vault, AWS, Kubernetes, Istio, Terraform, Helm
Developer Experience and Backstage.io
- Newly founded function to reduce the cognitive overload of developers
- Backstage.io as developer portal aggregating relevant information for the community
- Driving standardisation of solutions to common problems through SDKs, templates, best practices, trainings
- Implementing one-click microservice creation via copier templates
- Technology used: Backstage.io, CircleCI, copier
Embedded Site Reliability Engineering
- Site Reliability Engineers embedded in Product development teams
- Implemented day-time oncall for product teams on PagerDuty
- Driving optimisation for cost, availability and reliability
- Full observability based on Datadog and Prometheus/Grafana
- Technology used: Datadog, PagerDuty, Prometheus, Grafana Alertmanager, Terraform, Helm
From Restful APIs to Event driven architectures
- Implementation of event bus based on Strimzi Kafka, later Confluent Cloud solution
- Migration from RabbitMQ and RESTful APIs to Kafka
- knative as a Functions as a Service (FaaS) solution
- Read more: How Knative helps us to go FaaS
- Technology used: Strimzi Kafka, Confluent Cloud, Kubernetes, TIER SDK
KREUZWERKER GmbH
CENTRAL LOG, METRICS AND ALARMING SOLUTION
Micro Mobility Startup Berlin | 12.2018 - 09.2019
- Completely serverless AWS project - 250+ Lambda functions across 8 development teams
- Extensive integration of AWS service offerings to withstand massive scale
- Designed and implemented central log-, metrics- and alarming management
- Proposed and set up AWS multi-account infrastructure with strong security and auditing focus
- Shift to Kubernetes
- Read more: https://kreuzwerker.de/en/case/tier-mobility-a-success-story
- Technology used: serverless.com framework, Cloudformation, Hashicorp Terraform, Datadog, CircleCI CI/CD, Python, Node.js
MULTI-CLOUD, MULTI-BRANCH CI/CD SETUP
Radiation as a Service Startup Berlin | 05.2018 - 10.2018
- Fully automated CI/CD setup to support multi-branch development
- Multi-Cloud setup for legal requirements and vendor independence
- Abstraction of run-time environment via custom Jenkins library and use of Hashicorp tooling
- Technology used: AWS, Azure Germany, On-premise DC; Hashicorp Terraform, Packer and Vault; Jenkins CI/CD, docker; Python, Groovy, Bash
UNIFIED ATLASSIAN JIRA
Leading eCommerce Platform Berlin/Dreilinden | 12.2015 - 05.2016
- Three separate Atlassian Jira instances were to be unified
- Successfully moved 60 projects, 100 agile boards, 75,000 issues and some 250,000 comments.
- Read more: https://kreuzwerker.de/en/success-stories/atlassian-jira-migration
- Technology used: Adaptavist ScriptRunner, Groovy, Botron Configuration Manager, Bash, PostgreSQL, JSON/JQ