Sven Woltmann (HappyCoders.eu)

Java development, coaching, training

Sven Woltmann (HappyCoders.eu)
4.95 out of 5
Excellent
17 Reviews
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I'll keep you up to date with the latest tips + tutorials on Java programming, algorithms and data structures.

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http://www.happycoders.eu/de/newsletter/

Contact information

Sven Woltmann (HappyCoders.eu)
Berliner Allee 72
13088 Berlin
Germany

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Sven Woltmann

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100% Recommended
5 stars 17
4 stars 0
3 stars 0
2 stars 0
1 star 0
Quality
Value
Services
Implementation
Consulting
Customer service
Excellent (5.00)
Cost-performance ratio
Excellent (4.87)
Top competencies

Professionalism

5.00 out of 5
1 Reviews

Customer focus

5.00 out of 5
1 Reviews

Efficiency

5.00 out of 5
1 Reviews

17 Reviews on ProvenExpert.com

4.95 out of 5
Excellent
5.00 out of 5
Excellent
Recommendation
Sachlich sehr fundierter Artikel (Hexagonale Architektur). Die Sprache einfach gehalten. Zahlreiche hochwertige bildliche Veranschaulichungen an den richtigen Stellen. Artikelstruktur und visuelle Aufbereitung lassen keine Wünsche offen. Und nach der Theorie gibt es noch eine praktische Umsetzung dazu. Eine außergewöhnliche Erscheinung im Internet!
Customer review & rating for:
HappyCoders.eu Artikel
03/18/2025A.
5.00 out of 5
Excellent
Recommendation
I have worked with Sven for almost 2 years. In that time I was very impressed with the quality of his work, both analytical skills and coding skills. He goes very deep into any given problem and provides the best possible solution, I could trust him fully to deliver on time and on quality. There is no problem that he couldn’t solve. I would highly recommend his services to any company. He would be a valuable asset.
Customer review & rating for:
Programmierung
03/15/2025Julia R.
4.80 out of 5
Excellent
Recommendation
Highly Recommended! If you're looking to improve your tech skills, Svens HappyCoders.eu is a great place to start. Their courses and videos provide valuable knowledge in an easy-to-digest format. Whether you’re a student, a professional, or a hobbyist, you’ll find their content useful and engaging.
Customer review & rating for:
Programmierung
03/12/2025Kailas P.
5.00 out of 5
Excellent
Recommendation
I can confidently say that Sven's articles on hexagonal architecture are of exceptional quality and outstanding.

Furthermore, I also found the source code for the example project accompanying the articles excellent. It employs a fantastic pedagogical and professional approach, making it very realistic.

Likewise, I have been impressed by both the source code and the accompanying articles. I highly recommend them to anyone looking to enhance their knowledge and practical skills in implementing hexagonal architecture with Java.

I want to thank the author for the effort to create a complete Java example project that can be run across various frameworks. The project is exceptionally well-structured with branches, making it easy to navigate and understand the different scenarios in which hexagonal architecture can be applied with various infrastructure stacks. This resource seems unique online, and I have not encountered anything similar elsewhere.
Customer review & rating for:
HappyCoders.eu Artikel
11/09/2024Alfredo Rueda U.
5.00 out of 5
Excellent
Recommendation
Super useful tutorial that actually answered all my open questions.
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Customer review & rating for:
HappyCoders.eu Artikel
08/06/2024K.
5.00 out of 5
Excellent
Recommendation
I can highly recommend Sven for programming projects. He understood our complex requirements and delivered high quality solutions. Communication was always clear, Sven was open to feedback and was extremely keen to ensure that the delivered product met our expectations. Always happy to work with him again!
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Customer review & rating for:
Programmierung
05/03/2024M.
4.67 out of 5
Excellent
Recommendation
Good blog and content for experienced developers.
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Customer review & rating for:
HappyCoders.eu Artikel
04/19/2024R.
5.00 out of 5
Excellent
Recommendation
Hexagonal architecture concepts very well explained, with a concrete example. This is the only tutorial I've found on the web that's really useful to me.Thanks to the author.
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Customer review & rating for:
HappyCoders.eu Artikel
04/05/2024o.
5.00 out of 5
Excellent
Recommendation
Best technical articles in German on the subject of Java.
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Customer review & rating for:
HappyCoders.eu Artikel
12/16/2023Anonymously
5.00 out of 5
Excellent
Recommendation
I have worked with Sven for over seven years, and I have to say that he stands out among the Java developers that are around today. Sven's superb attention to detail and vast technical knowledge always provided top-quality, thoughtful, and professional outcomes in any work.

With Sven's excellent mentoring and guidance ability, I gained high impact skills in solving complex problems and reached a new level as a developer. I highly recommend him to anyone who is looking for an efficient, talented, and skilled programmer!
Customer review & rating for:
Programmierung
05/10/2023Daniil T.
5.00 out of 5
Excellent
Recommendation
Sven is not only a developer who thinks along, but also very complex projects on request. He is fast, reliable and extremely accurate. Sven plans and implements even very complex projects with outstanding quality. There are very few developers of his caliber.
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Customer review & rating for:
Programmierung
05/02/2023Fabien R.
5.00 out of 5
Excellent
Recommendation
I had the pleasure of working with Sven and am extremely pleased with his work. He took a lot of time to understand our requirements and then developed a customized solution that fits our needs perfectly. He is a true professional in his field. I can recommend Sven without reservation and would work with him again at any time. Thank you very much, Sven!
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Customer review & rating for:
Programmierung
04/28/2023T.
5.00 out of 5
Excellent
Recommendation
Sven works quickly, is solution-oriented and understands not only code, but also the wishes and requirements of teams and the product. 100% recommendation!
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Customer review & rating for:
Programmierung
04/28/2023A.
5.00 out of 5
Excellent
Recommendation
Rating for:
HappyCoders.eu Artikel
03/10/2025Anonymously
5.00 out of 5
Excellent
Recommendation
Rating for:
HappyCoders.eu Artikel
11/24/2024F.
4.67 out of 5
Excellent
Recommendation
Rating for:
HappyCoders.eu Artikel
07/17/2024Anonymously
5.00 out of 5
Excellent
Recommendation
Rating for:
HappyCoders.eu Artikel
04/27/2024Mert Y.
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All reviews and experiences about Sven Woltmann (HappyCoders.eu) are the subjective opinions of those who compose and submit them  |  The profile owner is responsible for the contents of this page  |   Profile active since 04/28/2023  |  Last update: 03/18/2025   |  Report profile

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