A selection of my project history since 2000, most recent first. For the general profile and skills, see the profile page.

VHV Gruppe Aktiv Software Securitas Beiersdorf Ford vestr KDO Sartorius Gascade Fino Arvato GLS Deutsche Post AG Telefónica O2 B. Braun

11/24 – 10/26 · Insurance / VHV Gruppe

Technical Consulting — Part time (80%)

Bugfixing and technical support of a software system for insurance brokers.

  • Role: Consultant · Team size: >20 · Method: Scrum
  • Tasks: Software and architecture consulting, agile coaching, software engineering, implementation, testing, bugfixing, DevOps, refactoring
  • Environment: Arch Linux · IntelliJ IDEA, Sublime, Obsidian · Local AI: Unsloth, Qwen 3, OpenCode
  • Stack: Java, Groovy, TypeScript · Spring, Spring Cloud, RabbitMQ, Kafka, Consul, Vault, Playwright · PostgreSQL, OpenSearch · SonarQube, Keycloak, Jaeger, ELK stack, Maven, Portainer, GitLab · Docker / Docker Swarm / cloud systems

05/18 – today · POP / CRM / Aktiv Software

Technical Consulting / Forward Deployed Engineer — Part time, on and off

Software development and consultation for the software product landscape.

  • Role: Consultant · Team size: 5 · Method: Small and medium sized assignments
  • Tasks: Implementation, test implementation, refactoring, bugfixing, infrastructure development, development, technical consultation, product development support, architecture support
  • Environment: Arch Linux, Windows 10 · IntelliJ IDEA, Visual Studio Express, Sublime, Obsidian
  • Stack: C#, Java, JavaScript, ES6 · ASP.NET Boilerplate, Entity Framework, AngularJS, Spring Boot, Apache Camel, Apache Storm, ReactJS, Sass, Bootstrap · MongoDB, MS SQL Server, PostgreSQL, Kafka, Apache Hadoop, Apache HBase · Apache Kylin, Zookeeper, Hive, Spark, Druid, Superset, Hue, make · Docker / Docker Swarm / in-house cloud systems, IIS, Apache, nginx, HAProxy, VirtualBox

09/22 – 11/23 · Securitas

Technical Consulting / Forward Deployed Engineer — Part time

Software development and consultation for a software product integration.

  • Role: Consultant · Team size: 3 · Method: XP
  • Tasks: Implementation, test implementation, refactoring, bugfixing, development, technical consultation, support
  • Environment: Debian Linux, Windows Server 2019 · IntelliJ IDEA, Sublime, DBVisualizer
  • Stack: Java, JavaScript, ES6 · Spring Boot, Apache Camel, Apache Storm, ReactJS, Sass, Bootstrap · Apache Kafka, Apache Hadoop, Apache HBase · Zookeeper, Hue, make · Docker / Docker Swarm

01/22 – 08/22 · Beiersdorf

Technical Consulting — Part time

Software development and consultation for a data and software migration.

  • Role: Consultant · Team size: 2 · Method: Small sized assignments
  • Tasks: Refactoring, bugfixing, development, technical consultation
  • Environment: Windows 10 · IntelliJ IDEA
  • Stack: Java, JavaScript, ES6 · Groovy, Node.js · ServiceNow, IIS

08/20 – 11/20 · Ford

Java Boot Camp — Full time

Introduction and instruction of employees into Java, Spring and web technologies.

  • Role: Teacher · Team size: 10 · Method: Front-class teaching / remote teaching
  • Tasks: Introduction into web technologies, Java basics, Spring basics, debugging, profiling
  • Environment: Windows 10 · IntelliJ IDEA
  • Stack: Java, HTML · Spring Boot, Spring Web, Hibernate, Spring Data · Gradle · MS SQL Server

07/19 – 10/19 · Insurance / VHV Gruppe

Technical Consulting — 3 months

Bugfixing and technical support of a software system for insurance brokers.

  • Role: Consultant · Team size: 20 · Method: Scrum
  • Tasks: Bugfixing, refactoring and refactoring advice
  • Environment: Windows 7, Arch Linux · IntelliJ IDEA
  • Stack: Java, Groovy · Spring, Spring Cloud, RabbitMQ, xStream, Consul, Zuul · PostgreSQL · SonarQube, Keycloak, Dynatrace, ELK stack, Maven · Docker / cloud systems

06/18 – 08/18 · Fintech / vestr

Technical Consulting — 2 months

Software development for a software product for bank certificate management.

  • Role: Consultant · Team size: 15 · Method: Scrum
  • Tasks: Implementation, test implementation, refactoring, bugfixing
  • Environment: Arch Linux, Linux, Windows 7 · IntelliJ IDEA
  • Stack: TypeScript, C, Java, Bash · GraphQL, Apollo, IBM MQi · PostgreSQL · Node.js, npm, nvm, RabbitMQ · Docker / cloud systems, Kubernetes

03/18 – 04/18 · Insurance / VHV Gruppe

Technical Consulting — 2 months

Bugfixing and technical support of a software system for insurance brokers.

  • Role: Consultant · Team size: 20 · Method: Scrum
  • Tasks: Bugfixing, refactoring and refactoring advice
  • Environment: Windows 7, Arch Linux · IntelliJ IDEA
  • Stack: Java, Groovy · Spring, Spring Cloud, RabbitMQ, xStream, Consul, Zuul · PostgreSQL · SonarQube, Keycloak, Dynatrace, ELK stack, Maven · Docker / cloud systems, AWS

02/18 – 03/18 · Youth welfare service / KDO

Technical Consulting — 10 days

Technical analysis and performance optimisation for a software system for the German youth welfare service.

  • Role: Consultant · Team size: 10 · Method: Scrum
  • Tasks: Software quality analysis, refactoring advice and support, code reviews and developer support, performance advice and support
  • Environment: Windows 10, Arch Linux · IntelliJ IDEA, Eclipse
  • Stack: Java · EMF, Teneo, Texo, Eclipse RCP · MS SQL Server · Eclipse · OSGi

09/17 – 12/17 · Medical technology / Satorius

Technical Consulting — 3 months

Technical analysis and maintenance of a touch screen based integrated front end for the product of a medical technology manufacturer.

  • Role: Consultant · Team size: 12 · Method: Scrum
  • Tasks: Software quality analysis, refactoring advice and support, code reviews and developer support, bug fixing
  • Environment: Xubuntu, Arch Linux · IntelliJ WebStorm
  • Stack: HTML5, CSS3, JavaScript · AngularJS · SQLite · Subversion · Node.js

05/17 – 09/17 · Power industry / Gascade

Technical Consulting — 4 months

Technical analysis and maintenance of an application for a power industry supplier.

  • Role: Consultant · Team size: 3 · Method: XP
  • Tasks: Software quality analysis, refactoring advice, support and documentation, code reviews and developer support
  • Environment: Windows, Arch Linux · IntelliJ IDEA, Sublime Text, Eclipse
  • Stack: Java SE 8, HTML5, CSS3, JavaScript · Apache Wicket, Hibernate · MS SQL Server · Subversion, SonarQube, Gradle · Tomcat

11/16 – 04/17 · Mobility / In-house

Stack / Product Development — 5 months

Development of generic solutions for the German electro-mobility sector.

  • Role: Technical lead · Team size: 5 · Method: Scrum
  • Tasks: Product development, technical consulting and transfer of generic concepts, architectural support, code reviews and developer support
  • Environment: CentOS, Arch Linux, Ubuntu · IntelliJ IDEA, Sublime Text
  • Stack: Java SE 8, HTML5, CSS3, TypeScript, JavaScript, Groovy, ECMAScript 6, XML · Spring, Spring Boot, SLF4J, JUnit, JOOQ, Apache CXF, AngularJS 1/2 · Redis, PostgreSQL, ElasticSearch · Git, Gerrit, Jenkins, SonarQube, Gradle, KarmaJS, Jasmine, Docker · Node.js, Tomcat Embedded

09/16 – 10/16 · Financial technologies / Fino

Web Application Development — 2 months

Development of a multi-client capable web application to support account transfer processes.

  • Role: Full stack developer · Team size: 12 · Method: Kanban
  • Tasks: Integration of an SSO solution, user rights concepts, printing services
  • Environment: Linux, Windows
  • Stack: Java, JavaScript · AngularJS, Dropwizard · MongoDB · Docker, RabbitMQ · Microsoft Federation, SAML

03/16 – 09/16 · Mobility / In-house

Stack / Product Development — 7 months

Development of generic solutions for the German mobility sector.

  • Role: Technical lead · Team size: 1–8 · Method: Kanban
  • Tasks: Product development, technical consulting and transfer of generic concepts, architectural support, rapid prototyping, API design and management, code reviews and developer support, technology evaluation
  • Environment: CentOS, Arch Linux, Ubuntu · IntelliJ IDEA, Atom, Sublime Text, Anypoint Studio
  • Stack: Java SE 8, HTML5, CSS3, JavaScript, Groovy, TypeScript, ECMAScript 6, XML · Spring, Spring Boot, Mule ESB, Camunda, SLF4J, JUnit, JSPM, JUnit 4, JOOQ, Apache CXF, Spring Cloud, APIKit · Redis, PostgreSQL · Git, Gerrit, Jenkins, SonarQube, Gradle, KarmaJS, Jasmine · Node.js, Tomcat / Jetty Embedded, Mule ESB

10/15 – 03/16 · Insurance / Arvato

Middleware / Front End — 6 months

Development of a middleware system with additional call center front end.

  • Role: Full stack developer · Team size: 8 · Method: Rational Unified Process / near shoring
  • Tasks: Support and de-escalation, implementation and unit testing, maintenance of the build environment
  • Environment: Windows 7, Arch Linux · IntelliJ IDEA
  • Stack: Java SE 8, HTML5, CSS3, JavaScript, Groovy · Spring, Spring Boot, Apache Wicket 6.5, SLF4J, jQuery, JUnit 4, Mockito, DMDWeb (in-house) · Oracle DB XE, Oracle DB 10 · VirtualBox, Git, Stash, Gradle, Jenkins · Apache Tomcat, Jetty

07/15 – 10/15 · Insurance / Arvato

Portal / Back End Development — 4 months

Maintenance of an outbound messaging system for supplemental pension funds (Riester).

  • Role: Full stack developer · Team size: 4 · Method: Rational Unified Process / near shoring
  • Tasks: Maintenance of a back end system for 1 release, maintenance of a call center application
  • Environment: openSUSE, Windows 7, Arch Linux · IntelliJ IDEA, Eclipse
  • Stack: JavaScript, HTML5, CSS3, Java SE 7 · Axis 1.4, jQuery, Apache Wicket 1.5, SLF4J, OpenL, JodaTime, JUnit 4, Xtend, JAXB 2, Jnario, Pride / DMDWeb / gengui / Coins / Spine (in-house) · Oracle DB XE, Oracle DB 10 · VirtualBox, SVN (Tortoise), Ant · Apache Tomcat, Apache, Jetty

04/15 – 07/15 · IT Services / In-house

Web / Product Development — 4 months

Development and design of a time tracking management system.

  • Role: Full stack developer · Team size: 4 · Method: Kanban
  • Tasks: Front end development and design, REST service development, bug fixing, testing and test development
  • Environment: Arch Linux · IntelliJ IDEA, Sublime
  • Stack: Java 8, Scala, JavaScript, HTML5, CSS3 · AngularJS, Play 2.3, Akka · Jasmine, KarmaJS, Play Tests · Grunt, Bower, Docker, Git, Gerrit, Youtrack, Jira, Confluence · Play 2 / Jetty, nginx, Tomcat Embedded

07/13 – 03/15 · Logistics / GLS

Web Application Development — 1 year 9 months

Maintenance and further development of a B2C / B2B logistics portal.

  • Role: Technical lead front end · Team size: 12 · Method: Scrum
  • Tasks: Front end development and design, REST service development, bug analysis and fixing, testing and test development, workshops
  • Environment: Windows XP · IntelliJ IDEA, IBM Rational Application Developer (RAD)
  • Stack: CSS, Java, JavaScript, HTML · AngularJS, LESS, Dojo/Dijit, Node.js, Spring MVC · Grunt, SVN, Jasmine, Karma · Apache HTTP, WebSphere

01/13 – 06/13 · Insurance / Arvato

Portal / Back End Development — 6 months

Maintenance of an outbound messaging system for supplemental pension funds (Riester).

  • Role: Full stack developer · Team size: 8 · Method: Rational Unified Process
  • Tasks: Maintenance of a back end system for 1 release, migration of a Swing application into a web front end, front end and design development, framework development
  • Environment: openSUSE Linux, Windows 7 · Eclipse, IntelliJ IDEA
  • Stack: JavaScript, HTML5, CSS3, Java SE 7 · Axis 1.4, jQuery, Apache Wicket 1.5, SLF4J, OpenL, JodaTime, JUnit, JAXB 2, Pride / DMDWeb / gengui / Spine / Coins (in-house) · Oracle DB XE, Oracle DB 10 · DB Visualizer, TortoiseSVN, Ant, Oracle VirtualBox, Office Communicator · Tomcat 7, Apache, Jetty

01/12 – 12/12 · Financial Technology / Sparda Datenverarbeitung eG

Portal Development — 1 year

Maintenance and development of a sales and distribution system for a bank.

  • Role: Full stack developer · Team size: 10 · Method: Scrum
  • Tasks: Maintenance and further development, testing and test development, bug analysis and fixing
  • Environment: Win XP SP3, OS/390, CentOS 6 · SpringSource Tool Suite / Eclipse
  • Stack: Java/JEE · JSF (MyFaces 1.2), Portlet API 2, Struts 1, WPS Public API, Google Guava, Apache Commons, SLF4J, Hibernate 3.2, JAX-WS, Axis 1.4, IBM WebSphere Portal 6.1, Apache FOP · DB2/LinuxZ64 · JBoss 4/JBoss 7, IBM WebSphere Application Server · SVN, Maven, Ant, Sonar, Hudson

09/11 – 12/11 · Logistics / Deutsche Post AG

Back End Development — 4 months

Further development of a multi-channel messaging system.

  • Role: Full stack developer · Team size: 3 · Method: Scrum
  • Tasks: Scrum support and implementation, setup of a continuous integration tool chain, security audit refactoring support, front end development, back end development
  • Environment: Linux, Windows XP · IntelliJ IDEA
  • Stack: Java 6 · SOPERA, Apache Wicket, JAXB, Apache CXF, Apache Camel, Spring 3 · Mockito, JUnit 4 · Maven 3, IceScrum · Tomcat 7

07/11 – 09/11 · Telecommunications / Telefonica o2

Portal Development — 2 months

Development of an e-commerce portal.

  • Role: Full stack developer · Team size: 8 · Method: Kanban
  • Tasks: XML based CMS integration, front and back end development, release support
  • Environment: Linux · SpringSource Tool Suite, Groovy IDE
  • Stack: Groovy 1.8, Java 6 · Spring 3, xStream · Mockito, TestNG, XMLUnit · Gradle, Maven 3 · Tomcat 7, Jetty 7

05/11 – 06/11 · Telecommunications / Telefonica o2

Portal Development — 2 months

Development of a customer self-care portal.

  • Role: Full stack developer · Team size: 6 · Method: Scrum
  • Tasks: eCRM back end facade integration, request caching and back end decoupling, front and back end development, release support
  • Environment: Linux · SpringSource Tool Suite
  • Stack: Java 6 · Spring 3, EHCache, Hibernate + Hades, Wicket, Apache CXF · TestNG, Mockito · Maven 3 · Tomcat 7, Jetty 7

05/10 – 05/11 · Telecommunications / Telefonica o2

SOA Development — 1 year 1 month

Maintenance and further development of a SOA landscape.

  • Role: Full stack developer · Team size: 1–2 · Method: Scrum
  • Tasks: Front and back end development, bug analysis and fixing, testing and test development, release support
  • Environment: Linux · Eclipse
  • Stack: Java/JEE, HTML, CSS, XML · EJB 2/3, Spring Framework 2.0.x (Webflow + MVC), Axis, JSP, JAX-WS, xStream, Xdoclets · Maven Plugin API, Maven 2, Ant · Selenium/Molybdenum, EasyMock/PowerMock, JUnit 3/4 · JBoss 4

11/09 – 04/10 · Medical technology / B. Braun

Portal Development — 5 months

Development of a document collaboration portal.

  • Role: Full stack developer · Team size: 1 · Method: XP
  • Tasks: Front and back end development, framework development, bug analysis and fixing, testing and test development, release support
  • Environment: Windows 2003 Server, AIX (CATALOGcreator via REST, SAP R/3 via JCO/Hessian) · Eclipse (m2eclipse, Spring IDE, QuantumDB)
  • Stack: Java/J2SE (v1.4.x) · Spring (core, context, web, security/acegi, JNDI, JMS, JDBC), Commons API, Hessian · Windows (DEV), SAP NetWeaver 7.0 on AIX (PRD, QaS), Mylyn, Maven, Sonar, Nexus, Hudson, Jira

03/09 – 11/09 · Medical technology / B. Braun

Portal Development — 6 months

Development of a document collaboration portal.

  • Role: Full stack developer · Team size: 1 · Method: XP
  • Tasks: Front and back end development, framework development, bug analysis and fixing, testing and test development, release support
  • Environment: AIX, Windows 2003 Server · Eclipse (Spring IDE, QuantumDB, m2eclipse)
  • Stack: SAP-KM, SAP R/3 via JCO/Hessian, CSS, JavaScript, Oracle DB, Java/J2SE (v1.4.x) · Spring (core, context, web, security/acegi, JNDI, JDBC), Javamail, SAP-KM/TREX APIs, GWT, IView API for portal integration, Hessian, Commons API · Jira, Mylyn, Maven, Hudson, Nexus, Sonar, SAP NetWeaver 7.0 on AIX (PRD, QaS), QaS and Windows (DEV)

09/08 – 02/09 · Medical technology / B. Braun

Portal Development — 6 months

Development of a document collaboration portal.

  • Role: Full stack developer · Team size: 2 · Method: XP
  • Tasks: Front and back end development, framework development, bug analysis and fixing, testing and test development, release support
  • Environment: AIX, Windows 2003 Server, SAP NetWeaver 7.0 on AIX (PRD, QaS), Windows (DEV), SAP-KM, SAP R/3 via JCO/Hessian · Eclipse (m2eclipse, Spring IDE, QuantumDB)
  • Stack: Java/J2SE (v1.4.x), JavaScript, CSS · GWT, Spring (core, context, web, security/acegi, JNDI, JDBC), Hessian, Commons API, Javamail, SAP-KM/TREX APIs, IView API for portal integration · Oracle DB, MS SQL Server · Jira, Mylyn, Maven, Sonar, Hudson, Nexus

08/08 – 09/08 · Medical Technology / B. Braun

Portal Development — 2 months

Development of an intranet management application.

  • Role: Full stack developer · Team size: 2 · Method: XP
  • Tasks: Front and back end development, framework development, bug analysis and fixing, testing and test development, release support
  • Environment: AIX, Windows 2003 Server, SAP-KM, B. Braun Service Layer via JMS, SAP NetWeaver 7.0 on AIX (PRD, QaS), Windows (DEV) · Spring IDE, Eclipse
  • Stack: Java/J2SE (v1.4.x), JavaScript, CSS · GWT, Spring (core, context, web, security/acegi), JMS, Commons API · Jira, Mylyn, Maven, Hudson, Nexus

2000 – 02/08 · Logistics / active logistics

Portal Development — 8 years

Development and maintenance of logistics solutions based on in-house frameworks. (This project entails a large part of my experience in active logistics. Please ask for further details as required.)

  • Role: Apprentice / Full stack developer / Technical lead · Team size: 1–6 · Method: XP / V-model
  • Tasks: Framework development and maintenance, application development and maintenance, technical consulting, project management
  • Environment: OS/400, Linux (Redhat, Mandrake, Slackware, SLES), Windows (NT, XP) · Eclipse (MAT, QuantumDB), BlueJ, jcreator, Visual Age for Java, Visual Studio, text editors
  • Stack: CSS, HTML, Java/J2SE, JavaScript, Visual Basic, Perl, PHP, Bash, SQL, PL/SQL, ILE-RPG400 · Commons API, AXIS, JDBC, JAXB, Servlet API, Swing, JavaMail · DB2/400, MySQL, PostgreSQL · Tomcat, IBM WebSphere on OS/400, Apache · soapclient, MooTools, jQuery, Ant, PHProject, Mantis, xplanner, PHPNuke, PostNuke