Niels Majer - Senior Software Developer

Q: Where is Niels based?

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

Q: What languages does Niels speak?

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

Q: How many years of experience does Niels have?

Niels has at least 17 years of experience. During this time, Niels has worked in at least 5 different roles and for 6 different companies . The average length of individual experience is 3 years and 10 months . Note that Niels may not have shared all experience and actually has more experience.

Q: What is Niels's latest experience?

Niels's most recent position is Senior Software Developer at Gruner + Jahr Deutschland GmbH .

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

In recent years, Niels has worked for Gruner + Jahr Deutschland GmbH and Government Agency .

Q: Which industries is Niels most experienced in?

Niels is most experienced in industries like Energy , Education , Media, and Entertainment and Publishing . Niels also has some experience in Government and Public Administration and Banking and Finance .

Q: Which business areas is Niels most experienced in?

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

Q: Which industries has Niels worked in recently?

Niels has recently worked in industries like Media, Entertainment and Publishing and Government and Public Administration .

Q: Which business areas has Niels worked in recently?

Niels has recently worked in business areas like Information Technology (IT) , Business Intelligence , and Product Development .

Recommended expert

Hamburg, Germany

Experience

Oct 2021 - Present

4 years 5 months

Hamburg, Germany

Senior Software Developer

Gruner + Jahr Deutschland GmbH

Company in media and publishing
Process automation and system integration
Implementation of a system for automatic parking space booking
Development of new infrastructure-as-code solutions with AWS CDK
Creation of CI/CD pipelines in GitLab
Migration of CloudFormation templates to AWS CDK
Provision of data for business intelligence
Further development of existing microservices
Technologies: Java, Spring Boot, Spring Security, Python, Amazon AWS (CDK, API Gateway, Cognito, SQS, S3, SNS, Lambda, DynamoDB, IAM, CloudWatch, EC2, VPC, Route53), Google Cloud Storage, Camunda Cloud, Apache Camel, Docker, Kubernetes, Rancher, Redis, Micrometer, Splunk, Microsoft Power Automate, JUnit, Wiremock, Mockito, GitLab CI/CD
Methods: Kanban, CI/CD, Pair Programming, TDD, Clean Code

Sep 2020 - Sep 2021

1 year 1 month

Berlin, Germany

Senior Software Developer

Government Agency

Development of interfaces in the context of internal security
Modernization of a monolith in an enterprise Java environment
Integration of external systems into the existing system landscape
Further development of the central application for case management
Development of new services with Spring Boot and Apache Camel
Interface design with OpenAPI
Introduction of Spring Boot and Spring MVC in the central legacy system
Technologies: Java, JAX-WS, JAXB, Spring Boot, Spring Data, Spring Security, Spring MVC, Apache Camel, Struts, WebLogic, Servlets, JAX-RS, CDI, Bean Validation, JSP, Vue.js, Bootstrap, JUnit, Mockito, REST-assured
Methods: Scrum, CI/CD, TDD, Clean Code

Mar 2019 - Jan 2020

11 months

Berlin, Germany

Technical Lead Developer

Aggreko Deutschland GmbH

Development of control software for a battery storage solution (core service for plant control)
Design and development of software and system architecture
Conception and development of custom interfaces
Coordination of business requirements for battery power plant management and optimized performance control with specialist departments
Test-driven development of features
Development of test tools with Rust
Onboarding new colleagues
Technologies: Java, Kotlin, Spring Boot, Spring Data, JMS, Apache Camel, Apache ActiveMQ, Prometheus, Grafana, Docker, OpenShift, MySQL, Python, Rust, actix-web, serde, JUnit, Mockito
Methods: Scrum, CI/CD, Pair Programming, TDD, Clean Code

Jan 2014 - Dec 2018

5 years

Berlin, Germany

Software Developer

Younicos GmbH

Development of algorithms for optimized performance control in battery storage systems
Design and testing of algorithms using numerical simulations
Integration of results into the product
Conceptualization and implementation of features in battery power plant management
Analysis of real-time data from production systems
Technologies: Java, Apache Camel, OSGi, Spring Boot, Spring Data, MySQL, Python, numpy, pandas, scipy, matplotlib, JUnit, Mockito
Methods: Scrum, CI/CD, Pair Programming, TDD, Clean Code

Jan 2013 - Dec 2013

1 year

Berlin, Germany

Consultant

Dr. Nagler & Company

Data management for market data in a high-risk banking environment
Implementation of a flexible Bloomberg BPIPE interface to connect to risk market data
Conducting process and system analyses
Coordination of functional and technical tests
Technologies: Java, Python, Bash, Oracle DB

Jan 2008 - Dec 2012

5 years

Berlin, Germany

Research Assistant

Technical University of Berlin

PhD thesis on “Nonlinear Gain Dynamics of Quantum Dot Semiconductor Optical Amplifiers”
Research in the field of semiconductor nanophotonics
Technologies: Python, numpy, pandas, scipy, matplotlib, C++

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 Energy (6 years), Education (5 years), Media and Entertainment (4.5 years), Government and Administration (1 year), and Banking and Finance (1 year).

Energy

Education

Media and Entertainment

Government and Administration

Banking and Finance

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 (12 years), Product Development (10 years), Research and Development (10 years), Business Intelligence (5.5 years), and Quality Assurance (1 year).

Information Technology

Product Development

Research and Development

Business Intelligence

Quality Assurance

Summary

Java/Kotlin full-stack developer with a backend focus and solid cloud and DevOps know-how

Special knowledge in data analysis/visualization with Python and relevant frameworks/libraries

Advocate of high code quality/clean code

Strong analytical skills

Skills

Programming/scripting Languages:

Java
Kotlin
Python
Rust
Javascript
Html 5
Css
Bash
Sql

Cloud:

Amazon Aws (Cdk, Api Gateway, Cognito, Sqs, S3, Sns, Lambda, Dynamodb, Iam, Cloudwatch, Cloudformation, Ec2, Route53, Vpc)
Google Cloud Storage

Databases:

Mysql
Oracle

Java Ee:

Jpa
Jaxb
Jms
Jax-ws
Jax-rs
Cdi
Bean Validation
Servlets
Jsp

Spring:

Spring Framework
Spring Mvc
Spring Boot
Spring Data
Spring Security

Python:

Numpy
Pandas
Scipy
Matplotlib

Rust:

Actix-web
Tokio
Serde

Testing Tools:

Junit
Mockito
Wiremock
Rest-assured

Devops/infrastructure:

Docker
Kubernetes
Prometheus
Grafana
Splunk
Micrometer
Redis
Apache Activemq
Linux
Jenkins
Gitlab Ci/cd
Ansible
Camunda Cloud

Tools/others:

Rest
Openapi
Swagger
Apache Camel
Osgi
Git
Gitlab
Jira
Confluence
Bitbucket
Microsoft Power Automate

Methods:

Clean Code
Tdd
Agile Software Development With Scrum And Kanban
Pair Programming

Languages

German

Native

English

Advanced

Education

Oct 2008 - Jun 2012

Technical University of Berlin

PhD in Physics · Physics · Berlin, Germany · Magna cum laude

Technical University of Berlin

Diploma in Physics · Physics · Berlin, Germany

Profile

Created

August 2025

Last Update

February 2026

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Frequently asked questions

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

Where is Niels based?

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

What languages does Niels speak?

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

How many years of experience does Niels have?

Niels has at least 17 years of experience. During this time, Niels has worked in at least 5 different roles and for 6 different companies. The average length of individual experience is 3 years and 10 months. Note that Niels may not have shared all experience and actually has more experience.

What roles would Niels be best suited for?

Based on recent experience, Niels would be well-suited for roles such as: Senior Software Developer, Technical Lead Developer, Software Developer.

What is Niels's latest experience?

Niels's most recent position is Senior Software Developer at Gruner + Jahr Deutschland GmbH.

What companies has Niels worked for in recent years?

In recent years, Niels has worked for Gruner + Jahr Deutschland GmbH and Government Agency.

Which industries is Niels most experienced in?

Niels is most experienced in industries like Energy, Education, Media, and Entertainment and Publishing. Niels also has some experience in Government and Public Administration and Banking and Finance.

Which business areas is Niels most experienced in?

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

Which industries has Niels worked in recently?

Niels has recently worked in industries like Media, Entertainment and Publishing and Government and Public Administration.

Which business areas has Niels worked in recently?

Niels has recently worked in business areas like Information Technology (IT), Business Intelligence, and Product Development.

What is Niels's education?

Niels holds a Doctorate in Physics from Technical University of Berlin.

What is the availability of Niels?

Niels is immediately available full-time for suitable projects.

What is the rate of Niels?

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