bahn.de is the biggest web shop in europe by revenue selling 400k tickets a day.
As senior developer in a scrum team I developed code for web and mobile frontends as well as backend code for:
- time and ride based ticket products, loyalty cards, secure barcodes
- regional passenger transport company integration into the long distance ticket offerings
- user account management and user billing statement self service
- mobile app interfaces to db-navigator
- customer product selection, configuration, check out interactions and order booking
- 3rd party APIs

Full stack development of a web shop in google appengine

development of a 2d design app where customers can create their own shirt design

payment integration of paypal express checkout

backend order processing system

implementation of custom SVG and font rendering

In a program to establish mobile payment with nfc in germany using a wallet app in connection with the "Global Platform" technology stack, my role was the single point of contact for vodafone at the korean vendor of the wallet software, a company called Corefire. My task was to understand the technical issues from daily operations of the java based system and fix them with the vendor teams in USA and Korea.

Continuous Integration Engineering, deployments
Full stack development
Search integration

Design and implementation of REST APIs with J2EE, Swagger, Springboot

Platform architecture and database design

System architecture for Cloud and implementation for scalable apps with Docker

Implement Kibana, Elastic Search REST API access for applications

Maintain the CI and deployment system

UX Graphic design and layout

Develop JS responsive web applications with Websockets

Implement Confluence & Jira REST API applications

System Engineering, Software Development

Design and realisation of a highly scalable Java J2EE components for DOS protection of the portal infrastructure

Java Platform Engineering, analysis and integration of software releases of the core applications of the biggest swiss mobile operator Web Portal

Architecture and implementation of a document management system as Java web application for over 2 million documents.