Freiberuflicher Informatiker (bitte kein AÜG / ANÜ, nur Remote)

ActiveDirectory authentication and authorisation for Linux (Oracle Linux 9)
Java / Groovy software engineering, distributed systems, mullti-threading

The first project was the migration of the eBay Kleinanzeigen website and associated services from a legacy Kafka cluster to multiple new Kafka clusters. The systems were running under Kubernetes, written in Java (8, 11, 17) and Kotlin, and used Spring and Spring Boot to provide both microservices and a monolith. The migration involved new Kafka and Mirror Maker 2 configurations, code cleanup and code modernisation. eBay Kleinanzeigen is part of Adevinta and some interaction with centrally  provided services was also required.
The second project was the migration of analytics data from a Hadoop-based platform to a DataBricks-based platform. My part in this project was the analysis of the existing Hadoop data feeds (Kafka / Flume), the onboarding of a new engineer, and the implementation of Kafka configurations and backend changes.

The project context is the area of commodities trading, in this case the trading of energy (power and gas), under an EnBW programme to replace on-prem legacy systems with cloud-based systems. The contract was to architect, design and develop a high volume, low-latency connector between a cloud-based Volue DeltaXE instance and EnBW on-premises backend systems (Endur, EV) / EnBW cloud-based systems (Trayport autoTRADER, Exxeta, EMSys VPP for renewables). The implementation involved AWS Lambda to provide scalable microservices. KRITIS relevance was important in the architecture and design of the Connector and the way in which DeltaXE is operated. The DeltaXE instance is used for Position Keeping, Asset dispatch and TSO / SSO Nominations. I was responsible for all security aspects of the project as well as for defining the deployment (Azure DevOps) and operations criteria and methodology.
The system was written in Java, defined a REST API and used AWS components: API Gateway, S3, Lambda, DynamoDB, Cognito, Certificate Manager, IAM, VPC, VPC Endpoints, NAT Gateway, Cloudwatch Logs/Metrics/Events, SNS and used Terraform and OnePlatform for provisioning.