Marcus Biel - Java Cloud Expert

Q: Where is Marcus based?

Marcus is based in Grünwald, Germany .

Q: What languages does Marcus speak?

Marcus speaks the following languages: German (Native), English (Advanced), Spanish (Intermediate) .

Q: How many years of experience does Marcus have?

Marcus has at least 7994 years of experience. During this time, Marcus has worked in at least 15 different roles and for 14 different companies . The average length of individual experience is 444 years and 1 month . Note that Marcus may not have shared all experience and actually has more experience.

Q: What is Marcus's latest experience?

Marcus's most recent position is Java Cloud Expert at Unknown .

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

In recent years, Marcus has worked for Unknown and maildroppa.com .

Q: Which industries is Marcus most experienced in?

Marcus is most experienced in industries like Information Technology (IT) , Banking and Finance , and Telecommunication . Marcus also has some experience in Healthcare , Insurance , and Retail .

Q: Which business areas is Marcus most experienced in?

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

Q: Which industries has Marcus worked in recently?

Marcus has recently worked in industries like Information Technology (IT) and Banking and Finance .

Q: Which business areas has Marcus worked in recently?

Marcus has recently worked in business areas like Information Technology (IT) , Product Development , and Marketing .

Recommended expert

Grünwald, Germany

Experience

Mar 2023 - Present

3 years

Java Cloud Expert

Unknown

Modernized and modularized a legacy monolith to enable independent team workflows
Migrated from Java 8 to Java 21 and from Spring Boot 2 to Spring Boot 3.3
Simplified Maven project structure, reducing build time from 15 minutes to 50 seconds
Converting architecture to a hexagonal DDD architecture with end-to-end integration tests using RestAssured and JUnit 5
Tools and technologies: Java 8-22, Spring Boot, Mockito, AssertJ, RestAssured, Hibernate, OracleDB, Flyway, REST, JSON, Docker, Kubernetes, AWS, Bitbucket, GitHub, SonarQube, IntelliJ IDEA Ultimate

Jul 2022 - Nov 2023

1 year 5 months

Software Engineer

Unknown

Designed, architected, implemented and tested a SaaS solution for a medium-sized customer in the financial sector
Tools and technologies: Java 11, Quarkus, Stripe, PDFBox, JUnit 5, Mockito, AssertJ, Hibernate, PostgreSQL, Flyway, REST, JSON, Docker, GitLab, SonarQube, IntelliJ IDEA Ultimate; Java 8, Java 11, Spring Boot, Kafka, JUnit 5, Mockito, AssertJ, JPA, H2, Microsoft SQL Server, Liquibase, REST, JSON, Lombok, Docker, Kubernetes, Jenkins, Git on Bitbucket, SonarQube, IntelliJ IDEA Ultimate

Jun 2021 - Jul 2022

1 year 2 months

Integration Engineer

Unknown

Designed, implemented, tested and maintained Spring Boot based microservices for credit card system integration of a large German financial institution in the UK market
Processed, validated and handled events in a Kafka-based high-concurrency system on Azure Cloud
Tools and technologies: Java 8, Java 11, Spring Boot, Kafka, JUnit 5, Mockito, AssertJ, JPA, H2, Microsoft SQL Server, Liquibase, REST, JSON, Lombok, Docker, Kubernetes, Jenkins, Git on Bitbucket, SonarQube, IntelliJ IDEA Ultimate

Feb 2021 - May 2021

4 months

Integration Architect

Unknown

Designed and architected a Spring Boot based microservice architecture for automated GwG-compliant identity verification
Integrated a remote provider for secure creation of electronic signatures (QES)
Tools and technologies: Java 8, Java 11, Spring Boot, JUnit 4, Mockito, AssertJ, JPA, H2, PostgreSQL, Flyway, REST, JSON, Lombok, Docker, Kubernetes, Jenkins, Git on GitHub, SonarQube, IntelliJ IDEA Ultimate

Apr 2020 - Dec 9999

7979 years 9 months

Remote

Lead Developer

maildroppa.com

Led a remote team of software developers, designers and technical writers to develop an email marketing automation SaaS tool
Tools and technologies:
Backend: Java 22, Quarkus, JUnit 5, Hibernate Panache, JAX-RS, RESTEasy, JSON, Jackson, Auth0, JWT/OAuth 2.0, Flyway, PDFBox, Stripe, Docker, DigitalOcean Cloud, GitLab, SonarCloud, IntelliJ IDEA Ultimate, Postman
Frontend App: React 18.x with React Router and React Hooks
Sales page: Fully responsive HTML5, Figma
SEO: Ahrefs, Semrush, Tagparrot, Google Search Console, NeuronWriter, Contentpace, Google Analytics, Plausible, Online Outreach

Aug 2019 - Mar 2020

8 months

Full Stack Developer

Unknown

Greenfield development of an online tool for visualization of healthcare insurance data with Angular frontend and Java 11 backend
Supported architecture design, implementation and testing of Java microservices with JUnit 5 and end-to-end REST interface testing with Postman
Tools and technologies: Java 11, Micronaut, JUnit 5, Mockito, AssertJ, JPA, H2, PostgreSQL, Flyway, REST, JSON, Lombok, Logback, Docker, Kubernetes, Jenkins, Git on GitHub, SonarQube, IntelliJ IDEA Ultimate, Postman

Mar 2019 - Jul 2019

5 months

Grasbrunn, Germany

Principal Product Manager Technical

Red Hat GmbH

Created vision for Red Hat's tools and technology and inspired professional software and systems engineers
Led Developer Experience strategies across multiple product teams
Responsibilities:
Creating technical content
Speaking at conferences
Empowering engineers by delivering hands-on workshops
Building partnerships with individuals, companies and organizations
Connecting with other engineers to identify how Red Hat can help them succeed
Gathering product feedback to inform engineering decisions
Supporting engineers on forums, social media, meet-ups and other channels

Jun 2013 - Feb 2019

5 years 9 months

Unterföhring, Germany

SOA Specialist

Vodafone Kabel Deutschland GmbH

Designed, developed, tested and maintained distributed large-scale resilient systems
Focus on backend/middleware development of SOA web services and batch jobs
Tools and technologies: Java 8, Spring 4, Spring Batch, JPA 2.1, Mockito, PowerMock, JUnit, Maven, SonarQube

Feb 2013 - Mar 2013

2 months

Munich, Germany

Software Architect

financial.com AG

Implemented load-balanced JBoss domain clustering for full-time availability and system resilience
Tools and technologies: JBoss AS 7.1, Apache 2.2, ModCluster 1.2, Linux, MySQL 5, Maven 3.0.4, Hudson 2.x, Nexus 2.x

Jul 2010 - Feb 2013

2 years 8 months

Munich, Germany

Senior Software Engineer

Wirecard AG

Processed NFC and credit card transactions in real-time and batch with high performance and reliability
Developed REST and SOAP based B2B and B2C communication and web frontend extensions
Specified design, architecture and implementation guidelines for the development team
Conducted interviews and acted as interface to product management
Tools and technologies: Java SE 6 & 7, Java EE 5, Spring 3.1, Hibernate 3.6, Tapestry 4, SOA (REST, SOAP), Maven 3.0.4, Jenkins 1.5, Nexus, Sonar Server, Oracle 11, Tomcat 7, Jetty 8/9, Eclipse 4.2, Linux

Jun 2009 - Jun 2010

1 year 1 month

Munich, Germany

Senior Software Developer

abs Fondsplattform

Developed UI for a SOAP-based stock-market ordering proxy
Introduced quality guidelines with Sonar Server and managed release and production rollout on a Tomcat cluster
Tools and technologies: Java SE 5 & 6, Java EE 5, Spring, Hibernate, Cocoon, SOA (XML, SOAP, Hessian), Liquibase, Maven 2+3, Hudson, Nexus, Sonar Server, Eclipse 3.5, Oracle 10, Tomcat 6, Linux

Jun 2007 - Apr 2009

1 year 11 months

Munich, Germany

Frontend Developer

Searchteq

Led SEO and XML local search interface used by Bing Maps, increasing unique visitors tenfold
Converted development projects from Maven 1 to Maven 2 and provided in-house training
Integrated Hudson and Nexus for CI environment
Frontend development with Java, HTML, CSS, AJAX for local search engine
Tools and technologies: Java SE 5 & 6, Java EE 5, Spring, Hibernate, SOA (XML, JSON), SEO, JSP + JSTL 1.1, Apache POI, HTML, CSS, JavaScript, AJAX, Maven 1+2, Hudson, Nexus, Tomcat, Linux

Aug 2006 - Mar 2007

8 months

Augsburg, Germany

Frontend Developer

NCR AG

Designed and implemented a retail cash management application in store environment using Java Swing and JGoodies Forms Framework
Tools and technologies: Java SE 5, Swing, JGoodies Framework, SQL, MS SQL, Tomcat 5.5, Eclipse 3.2

Apr 2006 - Jul 2006

4 months

Ulm, Germany

Frontend Developer (Working Student)

Innowake GmbH

Extended a PHP-based image database and XML parser
Developed an interface for a barcode scanner
Tools and technologies: Java SE 5, J2EE 1.4, Struts 1.2, PHP 4, XML, Maven 1, Apache, Tomcat 5.5, DB2, Eclipse 3.1

Jun 2004 - Sep 2004

4 months

Brisbane, Australia

Frontend Developer (Internship)

Digicon Ltd.

Refactored a Java CMS and implemented JUnit tests
Created acceptance tests with FitNesse and performed SEO optimization of a website
Tools and technologies: Java SE 1.4, J2EE 1.4, Servlets, JSP, SEO, Fit+FitNesse, JBoss, Eclipse 2.1

Apr 2004 - Jun 2004

3 months

Brisbane, Australia

Frontend Developer (Internship)

Site Ezy Ltd.

Implemented a PHP SMS module and developed VB.NET user interfaces with database access
Designed databases for MySQL and MS SQL Server
Tools and technologies: PHP 4, VB.NET, SQL, MySQL, MS SQL Server, Visual Studio, Dreamweaver

Sep 2002 - Feb 2003

6 months

Munich, Germany

Frontend Developer (Internship)

BMW AG

Developed a Struts-based user interface for querying an Oracle database of BMW vehicle parts
Tools and technologies: Java SE 1.4, J2EE 1.3, Struts 1.02, Tomcat 4.1, JDBC, SQL, Oracle, Eclipse 2.0

Jul 2001 - Aug 2001

2 months

Munich, Germany

Intern

PC Professional Magazine

Worked as a technical editor, participated in editorial meetings and researched magazine articles
Composed news flashes and performed hardware benchmarking

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 Information Technology (7983.5 years), Banking and Finance (6.5 years), Telecommunication (5.5 years), Healthcare (0.5 years), Insurance (0.5 years), and Retail (0.5 years).

Information Technology

Banking and Finance

Telecommunication

Healthcare

Insurance

Retail

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 (7993.5 years), Product Development (7987 years), Marketing (7980 years), Quality Assurance (1.5 years), and Strategy (0.5 years).

Information Technology

Product Development

Marketing

Quality Assurance

Strategy

Summary

Marcus is one of the world’s top Java experts. For over 20 years he is designing clean, simple, pragmatic software architectures for event based microservices running in the cloud. For his clients he mainly uses Spring or Spring Boot with Kafka, but also likes to use modern cloud-native frameworks such as Quarkus or Micronaut. His focus is on the customer and their product.

Marcus supports his customers in delivering stable, highly maintainable software – on time and on budget. To achieve this, Marcus relies on a detailed requirements analysis as well as a high test coverage with unit and integration tests and static code analysis tools like Sonar Source.

Marcus Biel (@MarcusBiel) is a well known and active member of the international Java community. In this context, he served the JCP for 2 years as an elected member of the Executive Committee, making an active and important contribution to the advancement of the Java programming language. Also, Oracle named him Developer Champion.

Marcus is a regular speaker at Java conferences all over the world, such as Oracle Code One San Francisco, JavaZone Oslow and JBCN Conf Barcelona. In 2019, he was listed as an "Ubiquitous Gold Speaker" by Heinz Kabutz.

Besides this, he works as a technical reviewer for renowned Java books such as Effective Java, Core Java SE 9 for the Impatient, Java by Comparison or the OCP Java SE 11 Programmer II Study Guide.

In 2015, Marcus started a Java blog and YouTube channel that makes Java accessible to passionate developers. There are many advanced tutorials that you can find online, but tutorials with a solid background like this one are rare. Today, the course is also available at freecodecamp.org and received a total of over 2 million views so far. His free ebook "Java for Passionate Developers" was downloaded almost 20.000 times so far.

Marcus has become well-known in the Java community, with a total of over 75 000 followers across various social media platforms. In 2017, the editorial team at jaxenter.com rated him #13 in their list of the world's top Java influencers.

Languages

German

Native

English

Advanced

Spanish

Intermediate

Education

Oct 2001 - Mar 2007

University of Applied Sciences Augsburg

Computer Science Degree · Computer Science · Augsburg, Germany

Profile

Created

January 2026

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Frequently asked questions

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

Where is Marcus based?

Marcus is based in Grünwald, Germany.

What languages does Marcus speak?

Marcus speaks the following languages: German (Native), English (Advanced), Spanish (Intermediate).

How many years of experience does Marcus have?

Marcus has at least 7994 years of experience. During this time, Marcus has worked in at least 15 different roles and for 14 different companies. The average length of individual experience is 444 years and 1 month. Note that Marcus may not have shared all experience and actually has more experience.

What roles would Marcus be best suited for?

Based on recent experience, Marcus would be well-suited for roles such as: Java Cloud Expert, Software Engineer, Integration Engineer.

What is Marcus's latest experience?

Marcus's most recent position is Java Cloud Expert at Unknown.

What companies has Marcus worked for in recent years?

In recent years, Marcus has worked for Unknown and maildroppa.com.

Which industries is Marcus most experienced in?

Marcus is most experienced in industries like Information Technology (IT), Banking and Finance, and Telecommunication. Marcus also has some experience in Healthcare, Insurance, and Retail.

Which business areas is Marcus most experienced in?

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

Which industries has Marcus worked in recently?

Marcus has recently worked in industries like Information Technology (IT) and Banking and Finance.

Which business areas has Marcus worked in recently?

Marcus has recently worked in business areas like Information Technology (IT), Product Development, and Marketing.

What is Marcus's education?

Marcus attended University of Applied Sciences Augsburg for Computer Science.

What is the availability of Marcus?

Marcus is immediately available full-time for suitable projects.

What is the rate of Marcus?

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