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Full Name
Grzegorz Piwowarek
Full Name
ACE Associate
Top Level Details
Job Role
Owner
Company
4Comprehension
Country
Poland
Top Expertise
Architecture
Focus Area
Java
About Grzegorz
Grzegorz Piwowarek is an independent trainer and consultant, Java Champion, and Oracle ACE. He is the lead of the Vavr project and the Warsaw Java User Group, and a long-time contributor to the Java ecosystem as a speaker, OSS author, and blogger at 4comprehension.com. There are persistent rumours that he only exists at compile time.
Expertises
Architecture
Microservices
Event Driven
Performance
Go
Continuous Integration and Deployment (CI/CD)
Home Page
http://4comprehension.com/
Links
Latest Contributions
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Implementing a PID Controller in Java
Feb 25, 2026 - Blog post -
Java
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Writing JDK8-Compatible Libraries with Java Platform Module System Support
Feb 15, 2026 - Blog post -
Java
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Implementing Efficient Last Stream Elements Gatherer in Java
Jan 31, 2026 - Blog post -
Java
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Avoiding Fake Drift in Unit Tests
Jan 06, 2026 - Blog post -
Java
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What Can a Java Developer Learn from Golang?
Oct 21, 2025 - Presentation - in-person or virtual - JDD 2025
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What Can a Java Developer Learn from Golang?
Sep 19, 2025 - Presentation - in-person or virtual - Confitura
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What Can a Java Developer Learn from Golang?
Sep 03, 2025 - Presentation - in-person or virtual - JavaZone 2025
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Accidental Time Travel with Wiremock, SimpleDateFormat and Fractional Seconds
Jul 15, 2025 - Blog post -
Java
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