
Holger Friedrich contributed to the OpenHAB ecosystem by engineering robust backend features, modernizing build systems, and improving release workflows across openhab-core, openhab-addons, and related repositories. He implemented Java 21 upgrades, enhanced CI/CD automation with GitHub Actions, and stabilized integration tests to support reliable, maintainable releases. Holger addressed dependency management using Maven and Dependabot, refined API documentation, and improved device integration for protocols like KNX and MQTT. His work included code refactoring, test infrastructure upgrades, and documentation improvements, demonstrating depth in Java, Shell scripting, and build automation. These efforts resulted in more stable builds, clearer APIs, and streamlined contributor experience.

Concise monthly summary for 2025-10 focusing on stability, test reliability, and documentation quality across core and addons. Delivered concrete fixes and improvements with clear business value: reduced runtime risk in metadata handling, aligned tests with core API changes, and corrected Modbus binding documentation for better user guidance. Each item is traceable to committed changes, enabling easier audits and future maintenance.
Concise monthly summary for 2025-10 focusing on stability, test reliability, and documentation quality across core and addons. Delivered concrete fixes and improvements with clear business value: reduced runtime risk in metadata handling, aligned tests with core API changes, and corrected Modbus binding documentation for better user guidance. Each item is traceable to committed changes, enabling easier audits and future maintenance.
September 2025 monthly summary: Delivered major test infrastructure upgrades across core integration tests, modernized code with Java 21 enhanced switch expressions, and improved cross-repo dependency alignment and developer documentation. Fixed critical LSP regression and path handling issues, stabilized Windows/test environments, and enhanced test configurations to support newer libraries. These efforts reduced test flakiness, improved compatibility with modern toolchains, and boosted contributor productivity.
September 2025 monthly summary: Delivered major test infrastructure upgrades across core integration tests, modernized code with Java 21 enhanced switch expressions, and improved cross-repo dependency alignment and developer documentation. Fixed critical LSP regression and path handling issues, stabilized Windows/test environments, and enhanced test configurations to support newer libraries. These efforts reduced test flakiness, improved compatibility with modern toolchains, and boosted contributor productivity.
OpenHAB - August 2025 monthly summary focusing on stability, API quality, and automation across core, addons, distro, webui, and iOS. The month emphasizes managed dependency upgrades, a controlled MQTT/HiveMQ upgrade path with a rollback for stability, API surface improvements, and enhanced testing/automation to support reliable releases.
OpenHAB - August 2025 monthly summary focusing on stability, API quality, and automation across core, addons, distro, webui, and iOS. The month emphasizes managed dependency upgrades, a controlled MQTT/HiveMQ upgrade path with a rollback for stability, API surface improvements, and enhanced testing/automation to support reliable releases.
July 2025 monthly summary focusing on delivering business value through release readiness for OH 5.1.0, code quality improvements, and automated dependency management across core repositories. Key improvements included Java code quality improvements in openhab-core, release preparation and dependency alignment for OH 5.1.0, a critical upgradetool dependency regression fix, new BasicUI chart interpolation options, and comprehensive Dependabot automation across webui, distro, and addons. The OH 5.1.0 release readiness efforts extended across distro, with app.bndrun alignment, enhancing speed to market. This work improves maintainability, security posture, and faster release cycles, enabling teams to ship features more reliably.
July 2025 monthly summary focusing on delivering business value through release readiness for OH 5.1.0, code quality improvements, and automated dependency management across core repositories. Key improvements included Java code quality improvements in openhab-core, release preparation and dependency alignment for OH 5.1.0, a critical upgradetool dependency regression fix, new BasicUI chart interpolation options, and comprehensive Dependabot automation across webui, distro, and addons. The OH 5.1.0 release readiness efforts extended across distro, with app.bndrun alignment, enhancing speed to market. This work improves maintainability, security posture, and faster release cycles, enabling teams to ship features more reliably.
June 2025: A focused month of CI/build modernization, stability hardening, and robustness enhancements across openhab-addons, openhab-core, openhab-distro, and openhab-webui. Delivered tangible business value through more reliable builds, safer defaults, and improved test coverage, enabling faster and safer releases.
June 2025: A focused month of CI/build modernization, stability hardening, and robustness enhancements across openhab-addons, openhab-core, openhab-distro, and openhab-webui. Delivered tangible business value through more reliable builds, safer defaults, and improved test coverage, enabling faster and safer releases.
Open summary for 2025-05 across openhab/openhab-addons, openhab/openhab-core, and openhab/openhab-distro. The month focused on delivering business value through CI/CD reliability, build compatibility, and maintainability improvements, while stabilizing tests and reducing noise in dependency updates. Key outcomes: - CI/CD PR rebuild workflow improvements across addons and core: consolidated rebuild logic into main workflows, enabled rebuilds via label and via forks with dedicated triggering and improved security, and refactored permissions and workflow organization for maintainability. - Maven 4 readiness and root/marker support: added top-level markers in .mvn directories and root markers to ensure Maven 4 compatibility and smoother root detection across repositories. - Chart axis readability enhancements: refined x-axis label spacing and width estimation to prevent label overlap in dashboards. - Dependabot Maven improvements: tuned Dependabot to focus updates on Maven development plugins, reducing noise from routine Maven dependencies. - Version management and test stability: downgraded JUnit from 5.12.1 to 5.11.4 where required to address integration/test issues introduced by newer versions, stabilizing test suites. Impact: - Faster, safer PR validation and fork contributions, reducing cycle time for contributors and maintainers. - Build pipeline resilience with Maven 4 compatibility across multiple repos, minimizing breakages and enabling smoother onboarding for Maven 4 users. - Cleaner dependency updates and more actionable security/upgrade signals for the Maven ecosystem. Technologies/skills demonstrated: - GitHub Actions / CI/CD orchestration, pull_request_target usage, label-based rebuild triggers, and fork permissions. - Dependency management strategy with Dependabot tuning for Maven projects. - Maven 4 readiness instrumentation and root marker strategies; JUnit version governance across modules. - Data-driven UI and chart rendering adjustments for improved UX in dashboards.
Open summary for 2025-05 across openhab/openhab-addons, openhab/openhab-core, and openhab/openhab-distro. The month focused on delivering business value through CI/CD reliability, build compatibility, and maintainability improvements, while stabilizing tests and reducing noise in dependency updates. Key outcomes: - CI/CD PR rebuild workflow improvements across addons and core: consolidated rebuild logic into main workflows, enabled rebuilds via label and via forks with dedicated triggering and improved security, and refactored permissions and workflow organization for maintainability. - Maven 4 readiness and root/marker support: added top-level markers in .mvn directories and root markers to ensure Maven 4 compatibility and smoother root detection across repositories. - Chart axis readability enhancements: refined x-axis label spacing and width estimation to prevent label overlap in dashboards. - Dependabot Maven improvements: tuned Dependabot to focus updates on Maven development plugins, reducing noise from routine Maven dependencies. - Version management and test stability: downgraded JUnit from 5.12.1 to 5.11.4 where required to address integration/test issues introduced by newer versions, stabilizing test suites. Impact: - Faster, safer PR validation and fork contributions, reducing cycle time for contributors and maintainers. - Build pipeline resilience with Maven 4 compatibility across multiple repos, minimizing breakages and enabling smoother onboarding for Maven 4 users. - Cleaner dependency updates and more actionable security/upgrade signals for the Maven ecosystem. Technologies/skills demonstrated: - GitHub Actions / CI/CD orchestration, pull_request_target usage, label-based rebuild triggers, and fork permissions. - Dependency management strategy with Dependabot tuning for Maven projects. - Maven 4 readiness instrumentation and root marker strategies; JUnit version governance across modules. - Data-driven UI and chart rendering adjustments for improved UX in dashboards.
April 2025: Delivered cross-repo improvements across web UI, core, and addons focused on security, reliability, and maintainability. Enhanced CI/CD pipelines, modernized codebase for Java 21 compatibility, and established automated dependency governance, resulting in faster builds, reduced risk, and improved test stability.
April 2025: Delivered cross-repo improvements across web UI, core, and addons focused on security, reliability, and maintainability. Enhanced CI/CD pipelines, modernized codebase for Java 21 compatibility, and established automated dependency governance, resulting in faster builds, reduced risk, and improved test stability.
March 2025: Implemented stability, security, and maintainability improvements across core, web UI, distro, and addons. Modernized APIs, realigned dependencies, and hardened CI pipelines to support faster, reliable releases while maintaining compatibility with Jakarta, JUnit 5, and current tooling.
March 2025: Implemented stability, security, and maintainability improvements across core, web UI, distro, and addons. Modernized APIs, realigned dependencies, and hardened CI pipelines to support faster, reliable releases while maintaining compatibility with Jakarta, JUnit 5, and current tooling.
February 2025 Monthly Summary: Delivered cross-repo stability improvements, enhanced observability, and comprehensive dependency upgrades across openhab-distro, openhab-core, and openhab-addons. Focused on business value through stability, security, and maintainability while strengthening telemetry and code quality.
February 2025 Monthly Summary: Delivered cross-repo stability improvements, enhanced observability, and comprehensive dependency upgrades across openhab-distro, openhab-core, and openhab-addons. Focused on business value through stability, security, and maintainability while strengthening telemetry and code quality.
January 2025 performance snapshot: Focused on delivering business value through feature enhancements, stability improvements, and modernization across the OpenHAB ecosystem. Major wins include KNX color-temperature support with mired handling, Java 21 modernization in core, comprehensive build/dependency stabilization, and alignment fixes for MQTT and web UI tooling to ensure reliable releases and smoother API interactions.
January 2025 performance snapshot: Focused on delivering business value through feature enhancements, stability improvements, and modernization across the OpenHAB ecosystem. Major wins include KNX color-temperature support with mired handling, Java 21 modernization in core, comprehensive build/dependency stabilization, and alignment fixes for MQTT and web UI tooling to ensure reliable releases and smoother API interactions.
December 2024: Spearheaded OpenHAB 5.0 release readiness across addons, core, webui, and distro, delivering platform upgrades and tooling refresh to enable a smooth release. Completed Java 21 migration in CI and core modules, removed Java 17 references, and updated test configurations to align with OH 5.0. Fixed release pipeline bugs: openhabian release type argument handling; webui CI problem matchers for Java 21; and rolled back the Start spifly early change after integration issues. Result: improved build stability, faster release cycles, and higher confidence in 5.0 readiness. Technologies: Java 21, CI/CD, dependency upgrades, test configuration, problem matchers, and release governance.
December 2024: Spearheaded OpenHAB 5.0 release readiness across addons, core, webui, and distro, delivering platform upgrades and tooling refresh to enable a smooth release. Completed Java 21 migration in CI and core modules, removed Java 17 references, and updated test configurations to align with OH 5.0. Fixed release pipeline bugs: openhabian release type argument handling; webui CI problem matchers for Java 21; and rolled back the Start spifly early change after integration issues. Result: improved build stability, faster release cycles, and higher confidence in 5.0 readiness. Technologies: Java 21, CI/CD, dependency upgrades, test configuration, problem matchers, and release governance.
November 2024 monthly summary: Delivered substantive business value by expanding energy-automation capabilities, improving reliability, and hardening security across openhab-addons and openhab-core. Key outcomes include expanded ISM8 support for heat pumps and solar data with richer data points and UOM alignment, robust channel processing and DPT mapping fixes, improved KNX diagnostics and handling of encrypted frames, and focused documentation/security upgrades. DSL usability improvements and color space utilities further enable rule authoring, while dependency hardening reduces exposure to CVEs.
November 2024 monthly summary: Delivered substantive business value by expanding energy-automation capabilities, improving reliability, and hardening security across openhab-addons and openhab-core. Key outcomes include expanded ISM8 support for heat pumps and solar data with richer data points and UOM alignment, robust channel processing and DPT mapping fixes, improved KNX diagnostics and handling of encrypted frames, and focused documentation/security upgrades. DSL usability improvements and color space utilities further enable rule authoring, while dependency hardening reduces exposure to CVEs.
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