Freelancer Software and System Engineering

1/2017 – 6/2017

- Design and implement a horizontally scalable realtime personalization engine
- AI Algorithms and rules can be plugged into the system to perform the personalization

Java (allg.)

1/2016 – 6/2016

Project lead for migrating of our social games stack from on premise datacenter to AWS without interruption of service

Ansible, Amazon Web Services (AWS)

9/2014 – 9/2015

- Design of a horizontally scalable and highly available system architecture to run newly developed games worldwide in different AWS regions providing low latencies for our players wherever they connect from
- Requirement was the capability to support 1 Mio concurrent users
- Adaptation of the old application to the new system (e.g. sharding)
- Took leadership of the project a few months before the launch
- Successfully launched our new game on the new system
- Supported our DevOps team in the first months after the launch in operating and further improving the system

Mysql, Postgresql, Java (allg.), Ansible, Amazon Web Services (AWS)

3/2012 – 6/2017

General responsibilities
- Responsible for the software architecture, technology choices, code quality, developer guidance
- Responsible for the infrastructure (keeping the huge codebase maintainable, further modularization of the application, technology upgrades, etc.)
- Supporting HR in recruiting
- Onboarding of new Java developers

Postgresql, Active Directory, J2EE, Java (allg.), Java Message Service, Representational State Transfer (REST)

5/2010 – 2/2012

- General responsibilities
- Mainly development in the Java based backend
- Technologies: Java, Spring, Hibernate, OpenMQ, Postgresql, Maven
- JavaEE Migration Project
- Migration from a spring based SOA architecture to a modularized, single JavaEE based deliverable, reducing downtimes from 3/month to 4-5 per year
- Introduction of a CI process
- Introduction of rolling deployments of the stateful platform
- Technologies: Java, Spring, Hibernate, Struts, OpenMQ, JMS, EJB, JPA, JSF, JUnit, Glassfish, Postgres, Maven, Jenkins
- Joined the OnCall Team
- OnCall duty
- Incident handling
- Incident analysis
- Technologies: Bash, Linux(CentOS), Nagios, Collectd

Postgresql, Apache Maven, Hibernate (Java), J2EE, Java (allg.), Spring Framework