Henning Plump enhanced the isy-logging module within the IsyFact/isyfact-standards repository by focusing on the maintainability and clarity of its test suite. He refactored Java test files to improve readability, corrected grammatical errors, and clarified both Javadoc and inline comments, ensuring that documentation was consistent and unambiguous. By aligning test documentation with translation corrections, Henning reduced confusion in failure messages and reports, which supports faster debugging and smoother onboarding for new contributors. His work, centered on Java and unit testing, did not alter runtime behavior but contributed to long-term code quality and reliability through improved test documentation and structure.