Rainer Diekmann - Enterprise Architecture Management / Backend Software Developer

Q: Where is Rainer based?

Rainer is based in Hamburg, Germany and can operate in on-site , hybrid , and remote work models.

Q: What languages does Rainer speak?

Rainer speaks the following languages: German (Native), English (Advanced) .

Q: How many years of experience does Rainer have?

Rainer has at least 30 years of experience. During this time, Rainer has worked in at least 20 different roles and for 35 different companies . The average length of individual experience is 1 year and 8 months . Note that Rainer may not have shared all experience and actually has more experience.

Q: What is Rainer's latest experience?

Rainer's most recent position is Enterprise Architecture Management / Backend Software Developer at Hamburg Police .

Q: What companies has Rainer worked for in recent years?

In recent years, Rainer has worked for Hamburg Police , Signal-Iduna Asset Management , Rheinmetall , Edeka , and RZF – Data Center of the Financial Administration .

Q: Which industries is Rainer most experienced in?

Rainer is most experienced in industries like Aerospace and Defense , Banking and Finance , and Government and Public Administration . Rainer also has some experience in Energy , Manufacturing , and Insurance .

Q: Which business areas is Rainer most experienced in?

Rainer is most experienced in business areas like Information Technology (IT) , Project Management , and Product Development . Rainer also has some experience in Quality Assurance (QA) , Research and Development (R&D) , and Business Intelligence .

Q: Which industries has Rainer worked in recently?

Rainer has recently worked in industries like Government and Public Administration , Information Technology (IT) , and Healthcare .

Q: Which business areas has Rainer worked in recently?

Rainer has recently worked in business areas like Information Technology (IT) , Product Development , and Project Management .

Recommended expert

Hamburg, Germany

Experience

Jun 2025 - Present

10 months

Hamburg, Germany

Enterprise Architecture Management / Backend Software Developer

Hamburg Police

Several projects in a police context
Model and document police procedures/projects with ArchiMate (as-is/to-be) in the context of P20 (Federal Criminal Police Office)
Create software architectures with microservices
POC development with Spring Boot/Docker/Kubernetes
Project size: 10 people
Enterprise architecture management with TOGAF and ArchiMate
Backend software development with Spring Boot
DevOps with Kubernetes
Implemented using: Java 17/21, Spring Boot 3, P20 architecture, TOGAF, ArchiMate

Nov 2024 - Mar 2025

5 months

Hamburg, Germany

Software Architect / Software Developer

Signal-Iduna Asset Management

Application system for asset managers
The application consists of multiple microservices that collect data via API interfaces and present it through a frontend (Angular Material). The backend uses Java with JEE/Dropwizard/Spring Boot
Project size: 20 people
Architecture design
Backend software development in Java/JEE
Frontend software development in Angular Material
Creating automated tests with Sahi Pro
Implemented using: Java 21, Gradle, Tomcat, Linux, JUnit, Mockito, REST, Kafka, JPA, Hibernate, JEE, Dropwizard, OpenShift, SQL Server, Flyway, Liquibase, Postgres, Spring Boot 3, JSON, JDBC, JPA, OWASP

Jun 2024 - Aug 2024

3 months

Germany

System Integrator / Software Integration Lead / Software (Verification) Test Manager

Rheinmetall

The German Armed Forces are switching their radios for all vehicles from analog to digital radio technology
Project size: 5 people
Developing concepts for systems and subsystems
Performing requirements analysis and management
Assisting in negotiating technical content with clients, partners, and suppliers
Supporting definition, planning, and control of work packages (as-is/to-be)
Coordinating and creating key system documents
Conducting technical reviews and audits
Preparing technical decision documents (e.g., make or buy)
Creating test concepts and documents
Monitoring current technical trends
System modeling in SysML
Implemented using: SysML, Enterprise Architect, Rhapsody, DOORS, CI/CD, OWASP

Mar 2024 - Apr 2024

2 months

Germany

Software Developer

Edeka

Maintaining legacy application
The application is technically outdated and will be replaced soon. Until then, the application must be kept operational (bug fixes, CVEs, updating third-party libraries)
Project size: 1 person
Bug fixing
Integrating security updates (CVEs)
Updating open-source libraries
Implemented using: Java 11/17, Struts, Maven, Tomcat, Linux, JUnit, Mockito, DBUnit, JMX, Eclipse, HTTP, TCP, SOAP, REST, JSON, JDBC, OWASP

May 2023 - Dec 2023

8 months

Germany

Software Architect / Consultant

RZF – Data Center of the Financial Administration

KONSENS - LAVENDEL
Private health insurers send their members' contributions to the BZSt (Federal Central Tax Office). The contributions are assigned to employees by tax number. Using the LAVENDEL process (KONSENS process), the assigned contributions are delivered to employers
Project size: 30 people
Creating architecture concepts
Architecture consulting for microservices implementation/migration compliant with TZAK-2025 using Spring Boot, JMS, Kafka, and containerization (Kubernetes)
Prototype implementation (PoC) for migration to a microservices architecture (KONSENS Appkit, Spring Boot)
Extending Lavendel KDialog with KVPV attributes (Java SWT)
Software quality analysis with SonarQube for the LAVENDEL system
Implemented using: Java 17, JBoss 7.4, Spring Boot 3, KONSENS Appkit, SWT, KDialog, Jira, Confluence, Docker, SOAP, REST, JMS, Kafka, Maven, Gradle, GitLab, OpenShift, MagicDraw, XMLSpy, XML, Oracle, JPA, Hibernate, ISO 27001 BSI Basic Protection, TZAK-2025, Linux, JUnit, Mockito, DBUnit, JMX, Eclipse, HTTP, TCP, SOAP, REST, BPMN, Quarkus, Cloud Native, JSON, XSD, JDBC, JPA, OWASP

Feb 2023 - Mar 2023

2 months

Germany

Software Architect / Software Developer

Atruvia

Atruvia Hub
Atruvia is migrating its internal intranet portal to a new portal developed with microservice technologies
Project size: 10 people
Architecture consulting regarding microservices implementation
Implemented Spring Boot backend (Spring Data JPA)
Implemented frontend with Angular
Implemented using: Java, Spring Boot 3, Jira, Confluence, Docker, REST, Gradle, Jenkins, Angular, OpenShift, Spring Data JPA, ELK Stack, Elasticsearch, MinIO, Linux, JUnit, Mockito, DBUnit, JMX, Eclipse, HTTP, TCP, SOAP, BPMN, Flyway, JEE, JBoss, REST, JSON, JPA, , OWASP

Mar 2022 - Dec 2022

10 months

Germany

Software Architect / Consultant

ITZBund

KVPV (ELStAM)
Private health insurance companies send their members' contributions to the Federal Central Tax Office (BZSt). The contributions are assigned to employees using their tax number. Through the ELStAM process, the assigned contributions are delivered to employers
Project size: 20 people
Created architecture concept using arc42
Architecture consulting for microservices implementation/migration with Spring Boot, JMS/Kafka, and containerization (Kubernetes)
Prototype implementation (PoC) for connecting to ELStAM
Defined migration path for the old monolithic application
Carried out software quality checks with SonarCube for the old ELStAM system
Implemented using: Java, Spring Boot, Jira, Confluence, ARC42, Docker, REST, Maven, Jenkins, Federal Cloud, JEE 7/8, JBoss 7.4, RabbitMQ, OpenAPI, AsyncAPI, Linux, JUnit, Mockito, DBUnit, JMX, Eclipse, HTTP, TCP, SOAP, Apache CXF, BPMN, XML, XSD, JDBC, JPA, , OWASP, Consensus

Jan 2022 - Feb 2022

2 months

Germany

Software Architect / Consultant

AOK Health Insurance

OTS – Online Appointment Service
AOK customers can book appointments at local branches through an online appointment service
Project size: 10 people
Architecture consulting for microservices implementation with Spring Boot, Angular, and Kafka
Prototype implementation
Deployment via Helm charts (Kubernetes)
Implemented using: Java, Spring Boot, Jira, Confluence, Docker, REST, Angular, Maven, OpenShift, Jenkins, Argo CD, Helm, Kubernetes, Elasticsearch, ELK Stack, Linux, JUnit, Mockito, DBUnit, JMX, Eclipse, HTTP, TCP, BPMN, JDBC, JPA, , OWASP

Apr 2021 - Dec 2021

9 months

Hamburg, Germany

Software Architect / Software Developer

Bundesdruckerei

Organ donation registry
Implemented several microservices and portals in the context of the OGR project (Organ donation registry)
Project size: 30 people
Developed microservices using Spring Boot
Integrated Keycloak via REST Admin API
Developed frontend components with Angular
Set up CI with GitLab
Deployed services with Docker on OpenShift
Architecture consulting for microservices implementation with Spring Boot
Implemented using: Java, Spring Boot, Jira, Confluence, Docker, REST, Angular, Maven, OpenShift, DDD, Hexagonal architecture, Keycloak, JPQL, Linux, JUnit, Mockito, DBUnit, JMX, Eclipse, HTTP, TCP, SOAP, BPMN, Apache Camel, JDBC, JPA, , OWASP

Feb 2021 - Mar 2021

2 months

Hamburg, Germany

Software Developer

Eon Digital Port

EnergieWächter II – Alarm management for municipal energy consumption
Extended the EnergieWächter project by integrating an additional AI component to detect anomalies in consumption data and generate alerts
Project size: 3 people
Extended existing Spring Boot service with a REST interface to connect the AI component
Defined REST API using OpenAPI
Analyzed consumption data with Python and Pandas
Set up CI with GitLab, deployed service with Docker on Azure Cloud
Implemented using: Java, Spring Boot, Jira, Confluence, Docker, Azure, REST, Data Science, Python, Linux, JUnit, Mockito, DBUnit, JMX, Eclipse, HTTP, TCP, SOAP, Flyway, JPA, , OWASP

Jan 2020 - Jan 2021

1 year 1 month

Hamburg, Germany

Software Architect / Software Developer

Eon Digital Port

Robin – creating offers for concession procedures
Replacing a VBA solution for generating proposal documents in Word with an Angular/Java application
Project size: 10 people
Software architecture defined as microservices architecture
Definition of the REST API with Swagger
Implementation of the Java backend with Springboot
Frontend development with Angular
Documentation of the architecture and the APIs
Requirements definition with the Product Owner
Security: authentication/authorization of the application with OAuth2 and JWT
Implemented using: Java, Springboot, Jira, Confluence, Docker, Azure, Postgres, REST, Angular, MyBatis, OAuth2, JWT, Linux, Junit, Mockito, DBUnit, JMX, Eclipse, http, tcp, Liquibase, Jpa

Nov 2019 - Dec 2019

2 months

Berlin, Germany

Software Developer

Webtrekk

Billing Console – export of invoice data
Export of invoice data from a web application to NetSuite as batch and manual export
Project size: 1 person
Java backend enhanced with CSV export
Angular 1 frontend enhanced
Requirements defined together with the client
Implemented using: Java, Spring, Jira, Confluence, MySql, REST, Angular, Linux, Junit, Mockito, JMX, Eclipse, http, tcp

May 2019 - Oct 2019

6 months

Hamburg, Germany

Software Developer

Eon Digital Port

EnergieWächter – alarm management for municipal energy consumption
Analysis of energy consumption data for anomalies and automatic notification of threshold exceedances
Project size: 5 people
Springboot service defined and implemented as a batch job
Requirements defined with the Product Owner
Testing the application
Pipeline implemented with gitlab and Docker
Agile approach using Scrum
Implemented using: Java, Springboot, Jira, Confluence, Docker, Azure, Postgres, REST, Data Science, Linux, Junit, Mockito, DBUnit, JMX, Eclipse

May 2018 - Apr 2019

1 year

Germany

Software Developer

Ponton GmbH

Enerchain – blockchain in energy trading
Orders in energy trading are persisted and distributed via blockchain technology (Tendermint/Go) using a Java API (jABCI)
Project size: 10 people
Software development using Java
Distributed architecture defined using Websocket
Implemented using: Blockchain, Tendermint, Java, Websocket, Angular, Jira, Confluence, Vagrant, Docker, ElaticSearch, Kibana, Linux, Junit, Mockito, DBUnit, JMX, Eclipse, Rest

Apr 2018 - May 2018

2 months

Hamburg, Germany

Software Architect (Review)

Kühne & Nagel

New Shipment Visibility
Analysis of the architecture of Springboot-based microservices for shipment tracking
Project size: 15 people (subproject)
Software review of the existing architecture and recommendations for improvements
Code review of the source code
Implemented using: Springboot, Java, JPA, Oracle, Spring, REST, JMS, git, JIRA, Docker, OpenShift

Oct 2017 - Mar 2018

6 months

Quickborn, Germany

Software Developer / Subproject Lead

Comdirect

Mifid II
Pre-clearance of costs for securities orders on the web and in the postbox
Project size: 20 people (subproject)
Software development with bank's own software stack based on J2EE
Support in software testing
Subproject lead for the postbox integration
Implemented using: Java EE, JPA, Oracle, Spring, JSF, JMS, git, JIRA, BitBucket, JBoss, Tomcat

Apr 2017 - Sep 2017

6 months

Hamburg, Germany

Software Developer / Analyst

Eurogate

COIN
Web application for managing container movements and EDI message processing
Project size: 2 people (subproject)
Development with the client's own Java framework
Coded PL/SQL procedures
Analysis and concept creation
Implemented using: Java, PL/SQL, JPA, Oracle, Spring, Swing, SWT, JBoss, Tomcat

Jul 2016 - Mar 2017

9 months

Germany

Software Architect / Subproject Lead

Hermes

ZSK – Central Service Customer
Development of a central customer service based on a microservice architecture with Spring Boot and ActiveMQ
Project size: 4 people (subproject)
Defined software architecture on a microservice basis with Spring Boot
Developed messaging between microservices with JMS
Subproject lead for ZSK
Analysis and concept creation
Authentication via JWT
Agile approach with Scrum
Implemented using: Java, Microservice, Spring Boot, JPA, JMS, ActiveMQ, Oracle, Docker, git, JIRA

Jun 2015 - Jun 2016

1 year 1 month

Hamburg, Germany

Software Architect / Subproject Lead

Signal-Iduna

MABS – Broker Order Processing System
Migration of broker order processing from MS Access to a JEE/AngularJS web portal application
Project size: 8 people (subproject)
Defined software architecture based on J2EE
REST API definition
Frontend with AngularJS
Subproject lead
Analysis and concept creation
Implemented using: Java, JEE 7, WebSphere, Jira, Confluence, MQSeries, AngularJS, JPA

Aug 2014 - Jun 2015

11 months

Quickborn, Germany

Software Architect / Subproject Lead

Comdirect

DC – COWIAS integration
Conversion of securities settlement communication from SNA to MQSeries and migration from C to Java/JEE
Project size: 15 people
Software architecture
Software development
Subproject lead
Concept creation (UML modeling)
Implemented using: Java, JEE, JBoss, C, Enterprise Architect, git, Jira, Stash, MQSeries, SNA

Feb 2013 - Aug 2014

1 year 7 months

Quickborn, Germany

Test Project Lead

Comdirect

TFE – Trading Frontend
Integration of an external trading frontend into in-house order core processes (OTC, stocks, bonds, derivatives)
Project size: 20 people
Test project lead (team of 5 people)
Test execution (manual and automated)
Software creation for automated tests
Implemented using: HPQC, Quicktest Professional, Oracle, Java, Splunk

May 2012 - Dec 2012

8 months

Hamburg, Germany

Technical Sub-Project Lead / Software Architect

Airbus Spares

ECDA – Enhanced Consumption Data Analysis
Forecasting parts consumption to determine optimal stock levels using statistics
Project size: 5 people
Technical sub-project lead
Architecture definition
Data warehouse design
Software development
Implemented using: Qt, C++, Java, PostgreSQL, SQL

Jan 2012 - Apr 2012

4 months

Neumünster, Germany

Release Manager

Panasonic

Car radio development for VW, Audi, Seat, Skoda
Modular infotainment platform (MIB) for Volkswagen
Project size: 400 people
Release manager
Planning integrations and releases
Coordination with build management
Leading the integration team (10 people)
Managing supplier deliveries
Implemented using: MS Project, Jira, Subversion

Oct 2008 - Dec 2011

3 years 3 months

Hamburg, Germany

Technical Sub-Project Lead / Software Architect

Airbus

@MOST – Systems Engineering
Research project to develop a fleet simulation and consumption analysis software for aircraft parts
Project size: 50 people
Technical sub-project lead
Architecture definition
Process models
Systems engineering (Sysml, IDEF, MLDesigner)
Software development
Implemented using: Sysml (Rhapsody, MagigDraw), IDEF (Core), simulation tool (MLDesigner, Matlab), Qt, C++, Booch

Oct 2007 - Oct 2008

1 year 1 month

Hamburg, Germany

Technical Sub-Project Lead / Software Architect

Airbus

Planet Inflight Application - Portal
Portal for the aircraft cabin based on AJAX techniques
Project size: 20 people
Technical sub-project lead
Software architecture
Quality assurance
Creating and executing module and load tests
Implemented using: MS Project, UML, AJAX, Postgres, JEE, Spring, JSF, Hibernate, Dojo, JSON, Android ADT, JMeter

May 2007 - Oct 2007

6 months

Hanover, Germany

Technical Subproject Lead / Software Architect

Bauberufsgenossenschaft

Workflow application
Supporting business processes using IBM Workflow Server, Swing clients and JEE application servers
Project size: 200 people
Technical subproject lead
Software architecture
Quality assurance
Implemented using: MS Project, Adonis, Innovator, IBM Workflow Server, DB2, J2EE, Hibernate

Jan 2007 - Mar 2007

3 months

Zürich, Switzerland

Business Analyst / Software Architect

Credit Suisse

Basel II – Large Exposure Reporting
Reporting credit risks and issuer risks at the ultimate partner level within Basel II
Project size: 10 people
Technical design
Functional design, Business Analyst
Software architecture
Quality assurance
Validation of reports using banking expertise (Basel II)
Implemented using: MS Project, Requisite Pro, Rational Rose, Power Designer, Oracle

Nov 2006 - Dec 2006

2 months

Hamburg, Germany

Release Manager / Project Manager

Hamburger Sparkasse

Migration project from z/OS to Solaris
Migration of host applications to Unix Solaris
Project size: 20 people
Release management
Quality assurance
RBE, Software architecture, Project management
Implemented using: MS Project, Doors

Apr 2006 - Oct 2006

7 months

Hamburg, Germany

Project Manager / Software Architect

Airbus

NSS-CC cabin architecture
Hardware and software system to provide internet access for passengers
Project size: 30 people
Requirements engineering
Project management
Quality management according to Airbus standards (ABDxxx, DO178B)
Software architecture, Systems engineering
Implemented using: MS Project, Doors, UML, SysML, Enterprise Architect

Feb 2005 - Mar 2006

1 year 2 months

Frankfurt, Germany

Business Analyst / Software Architect

Commerzbank

Basel II
Development of a Basel II calculation core using SAS and creation of a comparison implementation in Java for QIS4 and QIS5
Project size: 20 people
Functional analysis (Business Analyst), Software architecture, Test execution
Validation and verification of the Basel II calculation core results
Implemented using: SAS, Java, VBA, Oracle, DWH, PL/SQL, Crystal Reports

Jul 2002 - Nov 2004

2 years 5 months

Hamburg, Germany

Software Architect / Software Developer

Airbus

Cabin logbook as a web application
Capturing and analyzing aircraft defects via a J2EE web application and sending them via web services
Project size: 3 people
Analysis, design, software architecture, development, and testing
JEE architecture with Struts (MVC), Tomcat, JBoss/WebLogic, EJBs
Reporting via XSLT (PDF)
Implemented using: UML (RUP), Java, J2EE, Struts, Tomcat, XML, XSLT, .NET (C#), Axis, HTML, JavaScript

May 2001 - May 2002

1 year 1 month

Hamburg, Germany

Software Architect / Software Developer

Vereins- und Westbank

Internet integration of a portfolio management system
Connecting a central C++ server to web clients via an XML bus (SOAP) and BEA WebLogic cluster
Project size: 2 people
Creating a connectivity concept for web-based clients
Evaluating XML tools (Jaxb)
Development with EJBs on BEA WebLogic, frontend with JSPs
Performing module and load tests
Implemented using: UML (Together/J), Java, J2EE, JSP, EJB, BEA WebLogic, AbaXX Engines, XML (SAX, DOM, JDOM, XSLT, Jaxb), HTML, JavaScript

May 2000 - Apr 2001

1 year

Munich, Germany

Subproject Manager / Software Architect

Hypovereinsbank

Internet relaunch – banking/trading
Software architecture for the internet relaunch of the retail customer portal with IMS connection and EJBs
Project size: approx. 50 people
Creating the software architecture
IMS Connect for Java integration
Subproject management for the trading area (custody, order system, new issues)
Performing module and load tests
Implemented using: UML (Together/J), Java, J2EE, JSP, EJB, BEA WebLogic, Struts, HTML, JavaScript

Jan 2000 - Apr 2000

4 months

Frankfurt, Germany

Software Developer / Analyst

Dresdner Bank

Corporate finance portal
Developing an internet portal for corporate clients focused on internet brokerage
Project size: approx. 100 people
Creating the object model and use cases for internet brokerage
Implementing as server-side components with EJBs
Connecting backend systems via JDBC and MQSeries (Swift MT502)
Implemented using: J2SE, J2EE (JSP, Servlets, CORBA), JDBC, XML, UML, Oracle8i, JBuilder, application servers: BEA WebLogic, IBM WebSphere

Dec 1999 - Dec 1999

1 month

Germany

Trainer

SolveIT

Training in OOA/OOD and Java
One-week in-house training (2 days OOA/OOD, 3 days Java)
Project size: 8 trainees
Implemented using: J2SE, Swing, JDBC, Oracle8i, PowerPoint

Mar 1999 - Nov 1999

9 months

Germany

Project Manager / Software Developer

IXL

Supporting various web projects
Converting an applet solution into a server-side solution using servlets for a bank
Implementing web sites using servlets and JHTML
Responsibilities: project management, analysis, database design, development

Feb 1999 - Feb 1999

1 month

Germany

Trainer

Bijou Brigitte

Training in OOA/OOD and Java
Conducted two one-week in-house training sessions
Topics: use cases, class diagrams, Java language features, JDBC, Swing, JavaBeans, threads
Team size: 5 participants per session
Implemented with: J2SE, Swing, JDBC, Oracle8i, PowerPoint

Apr 1998 - Aug 1998

5 months

Oslo, Norway

Software Developer / Analyst

Norwegian Employment Office, Oslo

Object-oriented client-server project with OO4GL tools
Application for managing disabled unemployed people in Norway
Project size: 20 people
Front-end programming with Visual Parts in Visual Age
Fat-client architecture with direct Oracle database access
Implemented using: Visual Age Smalltalk, Rational Rose

Jan 1997 - Jan 1997

1 month

Kiel, Germany

Trainer

Regional Tax Directorate, Kiel

Training in OOA/OOD and Java
One-week in-house training for 3 participants
Implemented with: J2SE, Swing, JDBC, Oracle8i, PowerPoint

Apr 1996 - Jan 1999

2 years 10 months

Hamburg, Germany

Project Manager / Software Architect

Hamburg Police

Object-oriented client-server project with OO4GL tools
Developed the EPOS application for capturing and linking events, people, objects, and items
Project size: 3 people
Planning and specification of an agency application using Dynasty
Definition of an object-oriented 3-tier architecture
Specification and design of business objects
Implemented using: Dynasty, ERWin, Rational Rose

Nov 1995 - Apr 1996

6 months

Germany

Project Manager / Software Developer

Shipbuilding – CAD System

Object-oriented client-server project using CORBA
Designed a CORBA implementation (Orbix) to encapsulate PL/1 code in C++ classes
Project size: 3 people
Led project management, analysis, design, implementation
Implemented using: CORBA, PL/1, C++, Orbix

Jan 1994 - Apr 1996

2 years 4 months

Germany

Subproject Manager / Software Developer

Classification Society

Conceived and implemented a software system
Developed a software system for reliability calculation for ships (FEM and stochastic methods)
Project size: 2 people
Developed numerical methods (Monte Carlo, stochastic fields)
Implemented using: FORTRAN and C++

Jan 1994 - Apr 1996

2 years 4 months

Germany

Subproject Manager / Software Developer

Shipbuilding Clients

Multiple projects on PPS and production automation applications
Customer-specific enhancements for interfaces between PPS and CAD systems
Project size: 2 people
Implemented using: PL/1 and C++

Jan 1994 - Nov 1995

1 year 11 months

Germany

Project Manager / Software Developer

Shipbuilding – CAD System

Evaluation project for object-oriented databases
Tested OO databases as a replacement for relational databases
Designed a migration strategy
Project size: 2 people
Implemented using: ODMG, C++, Orbix, Objectivity

Industries Experience

See where this freelancer has spent most of their professional time. Longer bars indicate deeper hands-on experience, while shorter ones reflect targeted or project-based work.

Experienced in Aerospace and Defense (8 years), Banking and Finance (7.5 years), Government and Administration (5 years), Energy (2.5 years), Manufacturing (2.5 years), and Insurance (1.5 years).

Aerospace and Defense

Banking and Finance

Government and Administration

Energy

Manufacturing

Insurance

Business Areas Experience

The graph below provides a cumulative view of the freelancer's experience across multiple business areas, calculated from completed and active engagements. It highlights the areas where the freelancer has most frequently contributed to planning, execution, and delivery of business outcomes.

Experienced in Information Technology (26 years), Project Management (17.5 years), Product Development (13.5 years), Quality Assurance (8.5 years), Research and Development (5.5 years), and Business Intelligence (1 year).

Information Technology

Project Management

Product Development

Quality Assurance

Research and Development

Business Intelligence

Summary

Work experience in the IT field since 1991.
Since 1999 self-employed as an IT consultant for various industries.
Active in software architecture, software development, and testing. Focus in software architecture on designing multi-tier and microservices architectures. In modeling/analysis/design, applying object-oriented methods using UML/SysML and simulation. In data modeling using the ER method. In object-oriented application development using Java and C++.

Skills

Methodologies: Agile Approaches, Scrum, And Kanban
Database Design: Er Modeling
Software Architecture: Designing Software Architectures; Certified Isqi Software Architect Foundation Level
Ooa/d, Uml: Certified Omg Uml-professional (Fundamental)
Technologies: Jee Java Enterprise, Microservices (Springboot), .Net
Programming Languages: Java 11/17/21, C#, C++, C, Qt, Pl/1, Javascript/typescript
Ides: Eclipse, Intellij Idea, Visual Studio Code
Databases/db Technologies: Sql And Pl/sql, Oracle, Sybase, Ms Sql Server, Mysql, Postgres, Data Modeling (Er, Idef), Jpa/jdbc, Spring Jpa
Operating Systems: Windows, Unix, Linux, Mac Os X
Application Servers: Tomcat, Jboss, Ibm Websphere
Devops – Continuous Delivery: Docker, Docker Compose, Openshift/kubernetes, Helm Charts
Other Technologies/products: Spring, Spring Boot, Jms, Kafka, Hibernate Jpa, Jpql, Unit Tests (Junit, Mockito), Swing, Swt, Angular (Spa), Maven, Gradle, Rest (Json), Api Creation With Openapi, Html/css
Version Control Tools: Cvs, Svn (Subversion), Git, Ibm Clearcase
Experience In Technical Project Leadership With Hands-on Mentality, Sometimes With Team And Budget Responsibility.
Experience In The Basel Ii Environment, Participation In The Bundesbank's Qis4 And Qis5.
Experience In Object-oriented Modeling (Ooa/ood) Using Uml.
Experience In Data Modeling For Relational Databases And Data Warehouses (Dwh) Using The Er Method.
Experience In Applying Process Models (Rational Unified Process, V-model, Extreme Programming, Agile Processes, Scrum, And Kanban) In Practical Project Settings.
Experience Designing And Creating Functional Concepts And Client/server Architectures For Integration And Migration Of Existing Applications (Legacy, Host) To New Environments (Internet, Intranet) Using Middleware Technologies Like Java And C++.
Experience In Architecture And Development Of Web Applications Using Jee And Microservices.
Experience In Testing: Unit Testing With Junit, Stress Testing Websites With Jmeter, Developing Test Cases In Collaboration With The Business Department, Executing Acceptance Tests.
Experience Using Numerical Methods To Solve Mathematical Problems (Finite Element Methods, Monte Carlo Simulation, Stochastic Modeling, Finite Difference Methods).
Experience Building Internet Portals.
Experience As A Trainer With Good Didactic Skills.
Experience Coaching Projects.
Experience In Project Management With Personnel Responsibility.
Familiar With Common Planning Tools.
Team-oriented Working Style.

Languages

German

Native

English

Advanced

Education

University of Hamburg

Degree in Applied Mathematics: Numerical methods for solving partial differential equations for shock waves · Mathematics · Hamburg, Germany

Certifications & licenses

Certified ISQI Software Architect Foundation Level

Certified OMG UML Professional (Fundamental)

Profile

Created

January 2024

Last Update

January 2026

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Frequently asked questions

Do you have questions? Here you can find further information.

Where is Rainer based?

Rainer is based in Hamburg, Germany and can operate in on-site, hybrid, and remote work models.

What languages does Rainer speak?

Rainer speaks the following languages: German (Native), English (Advanced).

How many years of experience does Rainer have?

Rainer has at least 30 years of experience. During this time, Rainer has worked in at least 20 different roles and for 35 different companies. The average length of individual experience is 1 year and 8 months. Note that Rainer may not have shared all experience and actually has more experience.

What roles would Rainer be best suited for?

Based on recent experience, Rainer would be well-suited for roles such as: Enterprise Architecture Management / Backend Software Developer, Software Architect / Software Developer, System Integrator / Software Integration Lead / Software (Verification) Test Manager.

What is Rainer's latest experience?

Rainer's most recent position is Enterprise Architecture Management / Backend Software Developer at Hamburg Police.

What companies has Rainer worked for in recent years?

In recent years, Rainer has worked for Hamburg Police, Signal-Iduna Asset Management, Rheinmetall, Edeka, and RZF – Data Center of the Financial Administration.

Which industries is Rainer most experienced in?

Rainer is most experienced in industries like Aerospace and Defense, Banking and Finance, and Government and Public Administration. Rainer also has some experience in Energy, Manufacturing, and Insurance.

Which business areas is Rainer most experienced in?

Rainer is most experienced in business areas like Information Technology (IT), Project Management, and Product Development. Rainer also has some experience in Quality Assurance (QA), Research and Development (R&D), and Business Intelligence.

Which industries has Rainer worked in recently?

Rainer has recently worked in industries like Government and Public Administration, Information Technology (IT), and Healthcare.

Which business areas has Rainer worked in recently?

Rainer has recently worked in business areas like Information Technology (IT), Product Development, and Project Management.

What is Rainer's education?

Rainer attended University of Hamburg for Mathematics.

Does Rainer have any certificates?

Rainer has 2 certificates. These include: Certified ISQI Software Architect Foundation Level and Certified OMG UML Professional (Fundamental).

What is the availability of Rainer?

Rainer will be available part-time from April 2026.

What is the rate of Rainer?

Rainer's rate depends on the specific project requirements. Please use the Meet button on the profile to schedule a meeting and discuss the details.