Alexander Henne - Senior Software Developer / Software Architect

Q: Where is Alexander based?

Alexander is based in Trebur, Germany .

Q: What languages does Alexander speak?

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

Q: How many years of experience does Alexander have?

Alexander has at least 29 years of experience. During this time, Alexander has worked in at least 13 different roles and for 11 different companies . The average length of individual experience is 1 year and 1 month . Note that Alexander may not have shared all experience and actually has more experience.

Q: What is Alexander's latest experience?

Alexander's most recent position is Senior Software Developer / Software Architect at Industry, Web & Mobile .

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

In recent years, Alexander has worked for Industry, Web & Mobile , Telecommunications Industry , Finance & Insurance , Industry, and Mobile .

Q: Which industries is Alexander most experienced in?

Alexander is most experienced in industries like Information Technology , Banking and Finance , and Automotive . Alexander also has some experience in Insurance , Media and Entertainment , and Telecommunication .

Q: Which business areas is Alexander most experienced in?

Alexander is most experienced in business areas like Information Technology , Product Development , and Project Management . Alexander also has some experience in Business Intelligence , Quality Assurance , and Customer Service .

Q: Which industries has Alexander worked in recently?

Alexander has recently worked in industries like Information Technology , Banking and Finance , and Insurance .

Q: Which business areas has Alexander worked in recently?

Alexander has recently worked in business areas like Information Technology and Product Development .

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Trebur, Germany

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Experience

Apr 2025 - Present

1 year 3 months

Darmstadt, Germany

Senior Software Developer / Software Architect

Industry, Web & Mobile

Migration of a sensor monitoring application from a binary ASIP protocol to the WebSocket-based WinGuard protocol "AOP", including updating sensor states in the MSSQL database.
Supporting clients with requirements analysis and business clarification.
Migrating existing applications from Spring Boot 2 to Spring Boot 3 and 4 and upgrading to JDK 21.
Backend development and architecture for new features in a mobile application (data management, access control, REST API design), securing interfaces with OAuth2.
Implementing an encrypted chat solution based on a Matrix-Synapse server, including user administration via the Synapse Admin API and client integration with a Spring Boot application.
Connecting backend REST services to an Angular frontend, build process and automatic code generation with OpenAPI Generator (contract-first).
Implementing Java service clients for asynchronous REST calls, database integration with Spring Data, query optimization.
Technologies: Java 21, Clean Code, Spring Boot (2.x, 3.x, 4.x), MapStruct, REST, WebSockets, JPA, JPQL, Hibernate, Spring Data, Spring WebFlux, MSSQL, GitLab, JUnit 5, WireMock, Mockito, Jenkins, Maven, Bitbucket, SLF4J, Lombok, OpenAPI, Angular, Matrix-Synapse, nginx.

Jul 2023 - Mar 2025

1 year 9 months

Luxembourg, Luxembourg

Senior Software Developer / Lead Developer

Telecommunications Industry

API design and implementation of SOA and REST web services, transforming monoliths into a container-based microservice architecture using Spring Boot.
Migrating complex Inubit workflows to Java-based solutions, as well as optimizing and migrating existing systems and Camunda workflows.
Building and enhancing CI/CD pipelines and optimizing release and deployment processes.
Authentication with OIDC.
Extending existing Vaadin frontends and several Axon applications.
Developing new microservices for asynchronous message processing, scheduled report generation (Excel-based), transactional web applications, workflow applications, and scheduled import services with access to SMB, SFTP, and FTP shares.
Optimizing existing SOAP web services and Inubit workflows, extracting PDFs from SOAP messages and storing them on an SMB share.
Technologies: Java 8–21, Spring, Spring Boot, Spring Data, MapStruct, Liquibase, JPA, Axon, Inubit, Camunda, Keycloak, Lombok, SMBj, Apache POI, Git, GitLab, Jenkins, SonarQube, OWASP, Nexus, Docker, Kubernetes, AWS Cloud, WildFly, J2EE, PostgreSQL, MSSQL, Oracle, Jira, Confluence.

Apr 2021 - Jun 2023

2 years 3 months

Cologne, Germany

Senior Software Developer / Lead Developer

Finance & Insurance

Backend development for customer portal and postbox applications based on Spring Boot, including software architecture and API design.
Implementing contract-first and code-first REST services and connecting to internal systems with and without automatic code generation for web service stubs.
Implementing authentication and authorization with Keycloak and Spring Security (including step-up authentication and OIDC).
Developing REST and SOAP web services.
Data modeling, scheduling, PDF generation, code reviews, and migrating from Spring Boot 2 to Spring Boot 3.
Setting up CI/CD pipelines with GitLab, Docker builds and deployments to Kubernetes (AWS), and system monitoring with Kibana.
Mocking interfaces with MockServer and WireMock, including load tests (K6, Grafana) for critical services.
Technologies: Java 11, Spring Boot, Spring Security, JWT, OIDC (Auth Code Grant, Client Credentials Grant), REST, SOAP, Spring Data, Keycloak, Git, AWS Cloud, Kubernetes, Helm, Docker, Docker Compose, Lombok, Terraform, GitLab CI, Swagger, OpenAPI, ElasticSearch, Logstash-Encoder, Postman, WireMock, MockServer, MapStruct, Maven, OpenPDF, OpenCSV, FlyWay, OWASP, ShedLock, K6, JPA, Hibernate, JPQL, SQL, PostgreSQL, Clean Code, Jira, Confluence.

Oct 2020 - Jan 2023

2 years 4 months

Darmstadt, Germany

Senior Software Developer / Lead Developer / Software Architect (part-time projects)

Industry, Mobile

Alarm registry web application: software design, API design, and implementation of a web application for administrative tasks at the company fire department. Requirements management and prioritization of developer tasks. REST services development with Spring Boot, frontend development with Angular based on an OpenAPI v3 code-first approach. Development of a custom security solution including Windows login authentication and authorization via a proprietary rights model in MSSQL.
WinGuard server: designing and implementing a Java application to monitor sensors and update their states in the database. Implementing the ASIP protocol in Java, including scheduled database jobs and performance analysis.
Mobile application for customer communication: backend development for a mobile customer communication app, REST interface design, security concept, and authentication. PDF generation, video conversion, streaming, and integration of ChatGPT for content-based text suggestions.
Technologies: Java 11/17, Spring Boot, Spring Security, Spring Data, JPA, SQL, Angular, OpenAPI, Jenkins, Git, MSSQL, MariaDB, MySQL, ChatGPT, JUnit, Mockito.

Oct 2018 - Mar 2021

2 years 6 months

Wiesbaden, Germany

Senior Software Developer / Lead Developer

Finance & Insurance

Appointment management web application: new development with REST backend, Angular frontend, and PostgreSQL. Integration with Exchange and legacy systems and introduction of contract-first API design.
REST data services (guarantees): design and implementation of a Spring Boot application for connecting to REST services of an external provider, securing with Spring Security and connecting to AWS S3 storage.
Reporting data service: extending an existing data service with additional reports using the Criteria API and Hibernate predicates.
Camunda BPM: process modeling and implementation for partner changes, bonus data changes, and order processing. Integration of different systems and decommissioning of existing processes.
Kafka / ElasticSearch / Spring Batch: development of microservices for duplicate removal, partner data import, and partner search. Securing with OpenID Connect JWT tokens.
Technologies: Java 11, Spring Boot, Spring Security, Camunda, Kafka, ElasticSearch, Angular, PostgreSQL, AWS S3, Docker, Kubernetes, Jenkins, MapStruct, Hibernate.

Jul 2017 - Sep 2018

1 year 3 months

Wiesbaden, Germany

Senior Software Developer / SSO Consultant / Keycloak Developer

Finance, Credit Check

Spring Boot Microservice for user data synchronization between the authentication server and the shop application.
Keycloak development: integration with external shop system, migration strategy, automated login, step-up authentication according to the OIDC standard, and audit logging.
Design and implementation of step-up authentication in REST microservices and integration with Keycloak.
Development of a security module for offline token validation and extraction of user attributes.
Design and implementation of multiple microservices for an internal information system and PDF document generation.
Technologies: Spring Boot, Spring REST, Spring Security, Keycloak, OAuth2, OpenID Connect, Kafka, Java, Maven, Docker, PostgreSQL, Apache FOP, Jenkins.

Jul 2015 - Jun 2017

2 years

Eschborn, Germany

Application Architect / Senior Software Developer

Finance

DIF Webservice Framework Applications: implementation of a person search application (REST service), integration with LDAP and WebSSO systems.
Design and implementation of several filter components for the person search in a job search web application.
Interface engine, ETL application: design and implementation for the data model, persistence layer, and service layer.
Data modeling for application security: design and implementation of a database model for cross-application permission management with role concept.
Scriptella ETL Framework: development of a Java ETL software solution including build, deployment, backend, and web application with PrimeFaces (JSF).
Technologies: Java 7/8, Spring 4, Spring Boot, Spring Data, Spring Security, JSF, Scriptella, SAP HANA, Oracle, Hibernate, Maven, Git, Tomcat, Jetty.

Jan 2015 - Jun 2015

6 months

Frankfurt, Germany

Software Architect / Senior Software Developer

Software Agency

Financial products data analysis system: evaluation and sorting of financial products by different criteria and tabular display using Swing forms, including real-time data updates.
Technologies: JDK 1.7, Spring 3, XML, XPath, JUnit, TagSoup, JTidy, Maven, IntelliJ.

Sep 2013 - Dec 2014

1 year 4 months

Frankfurt, Germany

Software Architect / Senior Software Developer

Software Agency

Customer Sales Portal: interface definition and implementation of a single sign-on module (SAML2) and design of a new JAX-WS web service.
Football tournament management: design and development of a REST web service application with storage, statistics evaluation, and pairing logic.
Rules engine extension: development of new rule types for a vehicle configurator and integration into the existing application.
Data export application: implementation of web service export/import interfaces and data format definition with XSD.
Build optimization: conversion of build and release processes and dependency management for multiple Java projects.
Migration from XFire web services to JAX-WS web services and consolidation of web service applications.
Technologies: Java 6/7, Spring 2/3, Spring Security, JAX-WS, REST, Struts, JSF, Hibernate, MySQL, Oracle, Maven, Jenkins, SVN.

Mar 2013 - Apr 2013

2 months

Darmstadt, Germany

Software Architect / Senior Software Developer / Database Developer

Design and implementation of a lightweight web application for automated test execution and report generation in post-deployment testing.
Automatic generation of test documentation from Javadoc.
Technologies: Java 6/7, Maven, JUnit, Tomcat.

May 2012 - Jun 2013

1 year 2 months

Darmstadt, Germany

Software Architect / Senior Software Developer / Database Developer

System design for the NetPVR module within an IPTV multimedia platform.
Design and development of a framework for automated functional and non-functional tests.
Design and implementation of a performance test.
Technologies: UML2, Java, Spring, SOAP, SoapUI.

Jan 2012 - Jun 2012

6 months

Darmstadt, Germany

Software Architect / Senior Software Developer / Database Developer

Design and implementation of a statistics interface (XML/SQL) for an editorial system.
Performing data analysis in pivot form with SQL and PL/SQL as well as report creation.
Software architecture design for a URL validator.
Technologies: Oracle, PL/SQL, SQL.

Jul 2011 - Apr 2012

10 months

Darmstadt, Germany

Software Architect / Senior Software Developer / Database Developer

Design and development of an application for parallelized transcoding of audio live streams.
Design of a load balancing concept for dynamic stream distribution across multiple backend servers.
Technologies: Java, VLC, FFMpeg, MMS4J.

Jun 2011 - Jul 2011

2 months

Darmstadt, Germany

Software Architect / Senior Software Developer / Database Developer

Design and development of an application for testing XML-based services.
Automated retrieval, data analysis, and report generation in the form of XML delta files.
Technologies: Java, XML, JexamXML.

Sep 2010 - Dec 2011

1 year 4 months

Darmstadt, Germany

Software Architect / Senior Software Developer / Database Developer

System design and implementation of the business layer for an online radio project.
Extension and new development of a data warehouse system for the web radio application, including database modeling.
Design and development of ETL processes for automatic data migration and data synchronization.
Design and implementation of an authorization concept for access separation based on database schema separation.
Technologies: Java, Spring, JSF, Oracle 11g, PL/SQL, SQL Loader, Data Warehouse, Maven.

Apr 2010 - May 2010

2 months

Frankfurt, Germany

Technical Architect / Senior Software Developer / Senior Consultant

EAI architecture workshop: Creating the OSB reference blueprint and extending the EAI reference architecture.
Development of CXF and Metro web services using CodeFirst and ContractFirst approaches.
Technologies: CXF, Metro, WebServices, SOAP.

Sep 2009 - Dec 2009

4 months

Frankfurt, Germany

Technical Architect / Senior Software Developer / Senior Consultant

Setup and configuration of a generic application proxy (GAP) in the DMZ network for checking HTTP parameters.

Jun 2009 - Aug 2010

1 year 3 months

Frankfurt, Germany

Technical Architect / Senior Software Developer / Senior Consultant

FKF MIP project: Responsible for the technical architecture and development of an integration platform based on OSGi.
Development of an MVC framework using Scrum methodology.
Database modeling and creation of an authorization concept.
Technologies: Java, OSGi, Spring, CXF, JPA, Oracle, Scrum.

Jan 2009 - May 2009

5 months

Frankfurt, Germany

Technical Architect / Senior Software Developer / Senior Consultant

Architecture and further development of the rich client application (RCP) for the NVS ticket sales system.
Technologies: Eclipse RCP, Java.

Apr 2008 - Dec 2008

9 months

Frankfurt, Germany

Technical Architect / Senior Software Developer / Senior Consultant

Extensions, bug fixing, and architecture adjustments for a ticket sales system.
SEPA extension of the payment system and migration to BEA WebLogic.
Technologies: Java, JMX, WebLogic, ClearCase.

Apr 2001 - Apr 2008

7 years 1 month

Frankfurt, Germany

J2EE Senior Application Engineer / Team Lead

Software Agency

Functional leadership of Java development teams and technical responsibility for multiple web projects.
Architecture and development of an international vehicle configurator and integration of several applications.
Software architecture and development of a financing calculator for international web applications.
Design and development of modules for an online car portal and an online car marketplace.
Maintenance and overhaul of a web publishing system for car dealer web pages.
Optimization of development processes by introducing CI servers, SVN and automation of testing and deployment processes.
Technologies: Java (J2EE/J2SE), Spring, Struts, Hibernate, Oracle, MySQL, JUnit, WebLogic, Tomcat, Ant, CVS, SVN, PL/SQL.

Apr 2000 - Mar 2001

1 year

Hanover, Germany

Customer Support Engineer

IT Service

Programming of multicast distribution and implementation of system management strategies for about 500 computers.
Second-level support as part of the Enterprise Help Desk (EHD) at Volkswagen AG.
Technologies: Visual C++ 6, Visual Basic 5.0, NT Shell Script, CA-Unicenter, MS SQL.

Nov 1998 - Mar 2000

1 year 5 months

Hanover, Germany

IT Engineer, Data Analyst

IT Service

System administration, information security consulting, and maintenance of the data backup concept.
System management and network support with SMS 2.0, including design of a site hierarchy.
Database development (SQL) for process automation and refactoring of existing Access databases.
Design and implementation of solutions for the Y2K problem.
Technologies: Visual Basic 5, Access, MS SQL, SMS 2.0, Windows NT4.

Sep 1997 - Oct 1998

1 year 2 months

Merseburg, Germany

Internship in Mechatronics and IT Service

FH Merseburg

Internship as part of the engineering sciences/mechatronics study program.
Technologies: C++, Matcad, AutoCAD, Euclid.

Mar 1996 - Aug 1996

6 months

Software Developer

Patent Office

Software and database development for patent management.
Design of the network hierarchy based on Windows NT and database requirements.
Technologies: FoxPro 2.6, SQL, MS-DOS, Windows NT4.

Mar 1996 - Aug 1996

6 months

Software Developer

Transport Company

Database development for the HR department and general IT support.
Technologies: FoxPro 2.6, Pascal, MS-DOS, AutoCAD.

Industry Experience

See where this freelancer has spent most of their professional time.

Experienced in Information Technology, Banking and Finance, Automotive, Insurance, Media and Entertainment, and Telecommunication.

Information Technology

Banking and Finance

Automotive

Insurance

Media and Entertainment

Telecommunication

Business Area Experience

See which departments and functions this freelancer has contributed to most.

Experienced in Information Technology, Product Development, Project Management, Business Intelligence, Quality Assurance, and Customer Service.

Information Technology

Product Development

Project Management

Business Intelligence

Quality Assurance

Customer Service

Summary

Dipl.-Ing. (FH) with over 25 years of experience in object-oriented software development/software architecture, microservices, and enterprise applications for finance, telecommunications, and industrial companies. Focus on architecture, API design, backend development, security, and databases. Long-standing role as Lead Developer/Software Architect with responsibility for system design, refactoring, migrations, CI/CD pipelines, and technical leadership in agile teams.

Skills

Object-Oriented Software Development And Software Architecture, Api Design (Rest/Soap)
Analysis, Concept Design, Architecture Evaluation, Implementation, Build, Test, Documentation
Securing Interfaces/Applications, Sso
Data Analysis, Database Development, Database Modeling, Api Design, Etl, Bpm
Prototyping, Feasibility Analysis, Code Reviews And Effort Estimation
System Integration (Optimization, Refactoring, Migration, Databases, Interfaces)
Coaching, Technical Leadership, Strategy Consulting, Scrum

Languages

German

Native

English

Advanced

Russian

Advanced

Education

Sep 1997 - Oct 1998

FH Merseburg

Certificate · Engineering/Mechatronics · Merseburg, Germany

Sep 1990 - Feb 1996

State Baltic Technical University

Dipl.-Ing. (FH) · Automation Engineering

Oct 1988 - Jun 1990

Certificate · Programming and Computer Work

...and 1 more

Certifications & licenses

MCSE (Microsoft Certified Systems Engineer)

Statistics

Experience

Total positions 26

Experience in Information Technology 20 y

Avg length 1 y 3 m

Longest experience 7 y

Global Experience

Countries worked in 2 (Germany, Luxembourg)

Primary country Germany

Expertise

Recent roles Senior Software Developer / Software Architect, Senior Software Developer / Lead Developer, Senior Software Developer / Lead Developer / Software Architect (part-time projects)

Main industries Information Technology, Banking and Finance, Automotive

Main business areas Information Technology, Product Development, Project Management

Qualifications

Highest degree Master

Certifications earned 1

Profile

Created

June 2026

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Frequently asked questions

Have questions? Find more information here.

Where is Alexander based?

Alexander is based in Trebur, Germany.

What languages does Alexander speak?

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

How many years of experience does Alexander have?

Alexander has at least 29 years of experience. During this time, Alexander has worked in at least 13 different roles and for 11 different companies. The average length of individual experience is 1 year and 1 month. Note that Alexander may not have shared all experience and actually has more experience.

What roles would Alexander be best suited for?

Based on recent experience, Alexander would be well-suited for roles such as: Senior Software Developer / Software Architect, Senior Software Developer / Lead Developer, Senior Software Developer / Lead Developer / Software Architect (part-time projects).

What is Alexander's latest experience?

Alexander's most recent position is Senior Software Developer / Software Architect at Industry, Web & Mobile.

What companies has Alexander worked for in recent years?

In recent years, Alexander has worked for Industry, Web & Mobile, Telecommunications Industry, Finance & Insurance, Industry, and Mobile.

Which industries is Alexander most experienced in?

Alexander is most experienced in industries like Information Technology, Banking and Finance, and Automotive. Alexander also has some experience in Insurance, Media and Entertainment, and Telecommunication.

Which business areas is Alexander most experienced in?

Alexander is most experienced in business areas like Information Technology, Product Development, and Project Management. Alexander also has some experience in Business Intelligence, Quality Assurance, and Customer Service.

Which industries has Alexander worked in recently?

Alexander has recently worked in industries like Information Technology, Banking and Finance, and Insurance.

Which business areas has Alexander worked in recently?

Alexander has recently worked in business areas like Information Technology and Product Development.

What is Alexander's education?

Alexander holds a Master in Automation Engineering from State Baltic Technical University and a Bachelor in Engineering/Mechatronics from FH Merseburg.

Does Alexander have any certificates?

Alexander has 1 certificate: MCSE (Microsoft Certified Systems Engineer).

What is the availability of Alexander?

Alexander is immediately available for suitable projects.

What is the rate of Alexander?

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