Holger Dettmar - Software Developer

Q: Where is Holger based?

Holger is based in Hamburg, Germany .

Q: What languages does Holger speak?

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

Q: How many years of experience does Holger have?

Holger has at least 18 years of experience. During this time, Holger has worked in at least 9 different roles and for 16 different companies . The average length of individual experience is 1 year . Note that Holger may not have shared all experience and actually has more experience.

Q: What is Holger's latest experience?

Holger's most recent position is Software Developer .

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

In recent years, Holger has worked for Sick AG and NXP Semiconductors Germany GmbH .

Q: Which industries is Holger most experienced in?

Holger is most experienced in industries like Manufacturing , Aerospace and Defense , and Information Technology (IT) . Holger also has some experience in Energy , Education , and Chemical .

Q: Which business areas is Holger most experienced in?

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

Q: Which industries has Holger worked in recently?

Holger has recently worked in industries like Manufacturing and Aerospace and Defense .

Q: Which business areas has Holger worked in recently?

Holger has recently worked in business areas like Information Technology (IT) , Project Management , and Quality Assurance (QA) .

Recommended expert

Hamburg, Germany

Experience

Jul 2024 - Present

1 year 8 months

Software Developer

Gained familiarity with complex legacy software for controlling central ship systems (Ada, Java, C++).
Implemented tests to identify memory leaks.
Refactored existing project content and tests to object-oriented standards.
Identified and fixed bugs in existing distributed Java and C++ applications on a DONAR/CORBA network.
Products: Squish, NetBeans, MKS Integrity, DONAR, CORBA, DOORS, Windchill.
Skills: Python, Java, Linux, C++, Ada.

May 2022 - Jun 2023

1 year 2 months

Software Developer

Sick AG

Reengineered old Pascal and Visual Basic programs and reimplemented them in the in-house language ITEL (similar to C++).
Translated various MathCad calculations of gas concentration and dry calculations for calibrating gas measurement devices.
Developed a firmware updater including communication over hardware interfaces (RS232).
Implemented a complex task list to control an automated calibration.
Products: Table Curve, ITE Multicom, PuTTY, Mongo, Atlassian JIRA, MathCad.
Skills: MATLAB, C++, Java, hardware control, RS232.

Feb 2020 - Apr 2022

2 years 3 months

Software Developer, Software Architect, Project Lead

NXP Semiconductors Germany GmbH

Developed a detailed application concept with the client and evaluated different designs and tools for implementing parallel computations.
Designed the architecture and implemented the software following Clean Code principles.
Organized tests within the team with selected test users.
Products: Dask (Parallel Python Library), Jenkins, MPI.
Skills: High Performance Computing (HPC), Dask, Parallel Computing, Python, MPI, Linux, Windows, UML, software design, software architecture, Clean Code, OOP, Pandas.
Data Engineer.

Sep 2019 - Dec 2019

4 months

Software Developer

Zeiss Vision GmbH

Ported sorting software for eyeglass lens production from Windows 7 to Windows 10.
Ensured correct control of the order scanner and sorting hardware via a C/C++ library.
Reviewed and extended logging outputs.
Added an RFID interface to further automate the production chain.
Reimplemented the interface to the I/O card in C++ and to the RFID sensors in C#.
Products: Java, C/C++, RFID, Eclipse, Visual Studio, C#.
Skills: software development, embedded development, SQL.

Jun 2019 - Jul 2019

2 months

Software Developer, Trainer

MAN Energy Solutions SE

Translated all output texts of the blade planning program into English and implemented them in the source code.
Trained staff on the new software.
Products: Fortran, Eclipse, Java.
Skills: fluent English.

Jul 2018 - May 2019

11 months

Software Architect, Software Developer

Modernization of an in-house solution for calculating distillation columns (process engineering).
Development of a modular, future-proof architecture for easy extensibility and new user interfaces.
Implementation of the architecture in Python 3 and Qt 5 and migration of functionality from existing Visual Basic 6 code.
Creation of an automated test suite.
Development and implementation of a database concept to store historical calculation data.
Introduction of user rights management.
Calling existing Fortran routines from the new program module and processing the results.
Products: Visual Studio 2008/2017, Microsoft SQL Database, Doxygen, Python 3, Design Patterns, Test Driven Development, Unit Tests, Qt 5, Fortran.
Knowledge: Visual Basic 6, SQLAlchemy.

Feb 2018 - Jun 2018

5 months

Software Developer

RME

Extensions to the user interface with new functionalities.
Integration with data storage via DDS.
Products: QtCreator.
Knowledge: C++, Qt 5, DDS, PostgreSQL, SVN, CMake, Data Distribution Service.

Nov 2017 - Dec 2017

2 months

Software Developer

Hella Ventures

Research on suitable tools and methods.
Development of an algorithm to create a Brep geometry from pairs of coordinates using vector algebra.
Automatic meshing of the geometry with gmsh and control of the FEM solver CalculiX.
Feedback from the calculations to a neural network for automated optimization based on stiffness and volume.
Products: Eclipse, Python, gmsh, FEM calculation, NumPy, CalculiX, Ubuntu 16.04, PyCharm.
Knowledge: Mathematics, vector algebra, Machine Learning.

Mar 2017 - Nov 2017

9 months

Software Developer

Baker Hughes a GE Company

Integration of a test stand (FlowLoop) with the Predix Cloud to make time-dependent machine data available via suitable interfaces.
Familiarization with Predix and creation of an app for processing and visualizing machine data in the cloud.
Products: Eclipse, STS, Linux, Git, Predix, Postman, OPC UA, Intel Edison, Arduino, Docker.
Knowledge: Microservices, Cloud, REST, Big Data Analytics.

Jan 2016 - Oct 2016

10 months

Planning and Implementation

Siemens Mobility

Development of an application as an Eclipse plugin to make many behavior-driven test cases accessible (phrase browser).
Scanning existing folder structures and identifying stored test cases.
Implementation of a complex source code parser to extract relevant information.
Implementation of various sorting algorithms and search functions.
Presentation of the results as a TreeView and in search masks in the Eclipse plugin.
Products: GUI tests.
Knowledge: Eclipse RCP, Python, Python-behave, AutoIt, Java, JFace, SWT.

Jun 2014 - Dec 2015

1 year 7 months

Coordination with departments, design and implementation

MAN Diesel & Turbo SE

Integrating changes into the existing calculation process up to automatically generating CAD design drawings.
Geometric and thermodynamic calculations in Fortran and C++.
Exporting data via Java/J-Link into Pro-Engineer and creating drawings for manufacturing.
Products: Windows, MS Visual Studio, Fortran, C++, Java, Python, J-Link.
Skills: Pro-Engineer/Creo.

Apr 2014 - Nov 2017

3 years 8 months

Software Developer

Cloudplan

Developing server components and implementing requests, data storage, and formatting.
GUI development and integration with other processes.
Products: Atlassian JIRA, Confluence, MongoDB, Eclipse, QtCreator, VS-2013, Python, C++, Boost, Qt 5, QML, Git, Bitbucket.
Skills: HTTP, OpenSSL, TCP/IP, Multithreading.

Nov 2011 - Feb 2014

2 years 4 months

Design and development of various functionality extensions

MAN

Enhancing calculation processes for steam turbine design (thermodynamic design, geometric calculation, strength analysis).
Integrating additional profile parameters for turbine blades into the calculation process.
Geometric and thermodynamic calculations in Fortran.
Exporting data via Java/J-Link into Pro-Engineer and creating manufacturing drawings.
Creating a geometric model of the turbine rotor with mass and area moments of inertia.
Skills: Windows, MS Visual Studio, Eclipse, Fortran, VBA, Java, C++, Python.

Jun 2011 - Nov 2011

6 months

Object-oriented modeling and implementation of the analysis tool

Germanischer Lloyd

Application for evaluating fluid flow simulation results using OpenFOAM.
Calculating various scenarios to optimize ship balance.
Automated creation of documentation (presentations, charts, reports) from 3D calculation results.
Products: Ubuntu, Python, Shell Script, XML, Eclipse, UML, OpenFOAM, OpenOffice.
Skills: MS Office, Test Driven Development.

Jun 2010 - Mar 2011

10 months

Software Developer

DFKI, German Research Center for Artificial Intelligence

Supporting programming work on the Python pipeline and integrating new features.
Customizing, installing, and testing the pipeline for use on IBM compute clusters (10 h/week).
Skills: Ubuntu, Red Hat, Python, SciPy, NumPy, Eclipse, Shell Script, LoadLeveler.

Jun 2010 - Mar 2011

10 months

Software Developer

DLR, German Aerospace Center

Gathering requirements and modeling the autonomy concept for the Asteroid Landing System MASCOT in UML (use case, activity, sequence, component, and state diagrams).
Implementing, simulating, and testing the concept in MATLAB/Simulink/Stateflow.
Skills: Windows, UML, Enterprise Architect, MATLAB/Simulink/Stateflow.

Nov 2008 - Mar 2010

1 year 5 months

Scrum Master

Georg-Simon Ohm University of Applied Sciences Nuremberg

Developed a generator to create GENESIS games in a team of six spread across Germany.
Developed logic that allows supervisors to intuitively create games for the GENESIS console.
Skills: C++, Qt, Eclipse, SVN, Trac, Scrum.

Oct 2005 - May 2010

4 years 8 months

Software Developer

Airbus

Extending and applying the process chain for numerical flow simulation for aerodynamic aircraft developers on massively parallel UNIX systems (HPC cluster).
Designing and developing various function extensions and integrating them into existing software.
Planning, hosting, and delivering training/coaching sessions for the Centaur mesh generator.
Post-processing: developing custom solutions to extract parameters of interest.
Skills: Unix, Linux, Itanium, Centaur, DLR flow solver TAU, EnSight, Tecplot, Xmgrace, LaTeX, Python, ShellScript, LSF, MPI, Synfiniway, TauBL, Aerodynamics.

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 Manufacturing (8.5 years), Aerospace and Defense (6 years), Information Technology (6 years), Energy (4.5 years), Education (1.5 years), and Chemical (1 year).

Manufacturing

Aerospace and Defense

Information Technology

Energy

Education

Chemical

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 (16 years), Product Development (14 years), Research and Development (8 years), Project Management (3.5 years), Quality Assurance (3 years), and Production (1.5 years).

Information Technology

Product Development

Research and Development

Project Management

Quality Assurance

Production

Summary

Software engineering for complex technical systems, method & algorithm development, and process optimization in engineering.

Skills

Prototype Development
Tdd
Clean Code
Algorithm Development
Qt/qml
Matlab
Linux/unix
Java
Simulink
Method Development
Automation
Embedded
Fortran
Parallel Computing
Hpc
Simulation
Scrum
Data Engineer

Languages

German

Native

English

Advanced

Education

Nov 2008 - Jun 2014

Georg-Simon-Ohm University of Applied Sciences Nuremberg

Master of Engineering · Software Engineering and Information Technology · Nuremberg, Germany

Oct 2003 - May 2004

University of Wales, NEWI Wrexham

Bachelor of Engineering · Aeronautical Engineering · Wrexham, United Kingdom

Sep 1999 - Sep 2005

Braunschweig/Wolfenbüttel University of Applied Sciences

Diploma in Mechanical Engineering · Mechanical Engineering · Braunschweig, Germany

Certifications & licenses

iSAQB - Certified Professional for Software Architecture

Profile

Created

January 2026

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Frequently asked questions

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

Where is Holger based?

Holger is based in Hamburg, Germany.

What languages does Holger speak?

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

How many years of experience does Holger have?

Holger has at least 18 years of experience. During this time, Holger has worked in at least 9 different roles and for 16 different companies. The average length of individual experience is 1 year. Note that Holger may not have shared all experience and actually has more experience.

What roles would Holger be best suited for?

Based on recent experience, Holger would be well-suited for roles such as: Software Developer, Software Developer, Software Architect, Project Lead, Software Developer, Trainer.

What is Holger's latest experience?

Holger's most recent position is Software Developer.

What companies has Holger worked for in recent years?

In recent years, Holger has worked for Sick AG and NXP Semiconductors Germany GmbH.

Which industries is Holger most experienced in?

Holger is most experienced in industries like Manufacturing, Aerospace and Defense, and Information Technology (IT). Holger also has some experience in Energy, Education, and Chemical.

Which business areas is Holger most experienced in?

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

Which industries has Holger worked in recently?

Holger has recently worked in industries like Manufacturing and Aerospace and Defense.

Which business areas has Holger worked in recently?

Holger has recently worked in business areas like Information Technology (IT), Project Management, and Quality Assurance (QA).

What is Holger's education?

Holger holds a Master in Software Engineering and Information Technology from Georg-Simon-Ohm University of Applied Sciences Nuremberg, a Bachelor in Aeronautical Engineering from University of Wales, NEWI Wrexham and a Bachelor in Mechanical Engineering from Braunschweig/Wolfenbüttel University of Applied Sciences.

Does Holger have any certificates?

Holger has 1 certificate: iSAQB - Certified Professional for Software Architecture.

What is the availability of Holger?

Holger is immediately available full-time for suitable projects.

What is the rate of Holger?

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