As a software engineer I have expert level knowledge in constructing, developing and running high traffic web applications. I embrace open source software and am passionate about agile software development with Scrum. I am metric driven, have a passion for log management and love to talk about my findings at conferences and meetups.
Engineering Lead (CTO)
As CTO I am accountable for developing and operating the shopping24 product search platform. With 20 engineers I maintain the api and search backend based on Apache Solr, the product backend systems (Java) and the portal frontends (PHP). I code on a regular basis in both operations and search and assist the teams in system- and software architecture challenges.
- Insourcing of server operations: Development of a centralized configuration management using Ansible. Setup of a hybrid cloud hosting using bare metal, VMWare and KVM hypervisors as well as Amazon AWS. Recently pushing the transition into containerization using Docker, Kubernetes and Ceph as distributed storage.
- Design and implementation of a inner source e-commerce search solution for the Otto Group based on Apache Solr. Onboarding and consulting of several Otto Group companies like otto.de and Limango.
- As a in-house consultant I joined the implementation of the e-commerce search at otto.de and Limango. Implemented technical and relevance search monitoring, extended the CI/CD pipeline to do blue/green deployments.
- Building and eventually spun off a SaaS to manage Google and Bing ads at large scale. Wrote an entity extraction as a Apache Solr plugin in order to categorize ad terms. The software is used by multiple tenants inside the Otto Group.
- Implementation of a Scrum of Scrums on company level, introduced cross functional Scrum teams and lean project management.
- Apache Solr
- Spring Boot
- Java 11
Team lead Java development
Team lead of a team of 4 developers and up to 6 freelancers. Responsible for restructuring and refactoring the Java API and product management backend.
- Recruitment and training of the Java development team. Insourcing of Java development and application support for the existing Java applications.
- Review of the existing system and software architecture. Refactoring towards an elastic and service oriented architecture. Moved traffic and storage intensive data to Amazon AWS.
- Introduced Scrum as development process. Established a modern Java development infrastructure for Continuous Integration und Continuous Delivery.
- Conceptual design and implementation of a modular REST api for delivering affiliate product data based on Apache Solr.
- Centralizing logging, server, application and business metrics for real time analysis.
- Apache Maven
- Amazon EC2
- Amazon S3
- Amazon CloudFront
- Apache Solr
- Apache Hadoop
- Apache Mahout
- New Relic
Software Architect Java
Developer, architect and in-house consultant for Java based projects focusing on integrating legacy systems into modern web UIs. Technical lead for inter- and intranet web applications. Maintainer of the Java development and continuous integration infrastructure.
- Prepared and led advanced in-house Java, Spring Framework, Maven & Eclipse trainings
- Technical team lead for a web application, serving information about insurance contracts and correspondence to customers
- Technical team lead for a insurance broker web application that integrated online shopping systems and insurance calculators in a single-sign-on and -off domain
- Switched the complete Java codebase from building with Ant to Maven, maintained buildserver for continuous integration and Maven infrastructure components
- Created an Eclipse based distribution platform for remote offline viewing of data warehouse data cubes
- Eclipse RCP
- Spring Security
- Central Authentication Service (CAS)
- IBM DB2
- IBM Content Manager
- IBM MQSeries
- Websphere Application Server
Software engineer & server administrator
Acquired and implemented Java and PHP development jobs, one customer being Deutscher Ring insurance. Gained knowledge of Linux server administration in high traffic environments as systems administrator for transfermarkt.de.
- Debian Linux
Software developer PHP & Perl
Developed custom tailored applications for german high traffic websites in PHP and Perl.
- LAMP stack
Skills & Tools
- Learn To Rank (LTR)
- Travis CI
- Amazon AWS
- Road bike
- Landscape photography