
Krzysztof Piaskowy contributed to the software-mansion/react-native-reanimated repository by modernizing animation architecture, optimizing build systems, and improving cross-platform stability. He refactored core components to support the new React Native architecture, introduced a native event loop for worklet runtimes, and enabled dynamic frame rates on ProMotion displays. Using C++, TypeScript, and CMake, Krzysztof streamlined code by removing legacy modules, reduced binary size through linker optimizations, and enhanced developer experience with feature flagging and improved testing utilities. His work addressed compatibility with evolving React Native and Hermes versions, demonstrating depth in performance tuning, maintainability, and collaborative cross-repo problem solving.

2025-10 focused on stabilizing cross-repo navigation and Hermes integration. Delivered critical fixes to react-native-worklets for Hermes v1 compatibility and to react-native-screens for reliable custom swipe-back transitions, reducing runtime issues and improving user experience on updated React Native environments. These fixes enhance platform stability, performance, and developer ergonomics across two core libraries in the React Native ecosystem.
2025-10 focused on stabilizing cross-repo navigation and Hermes integration. Delivered critical fixes to react-native-worklets for Hermes v1 compatibility and to react-native-screens for reliable custom swipe-back transitions, reducing runtime issues and improving user experience on updated React Native environments. These fixes enhance platform stability, performance, and developer ergonomics across two core libraries in the React Native ecosystem.
September 2025: Key improvements across the react-native-reanimated project focusing on API extensibility, build performance, and binary footprint. External executeSync is now available outside Bundle Mode, enabling libraries like react-native-audio-api. Build times were significantly improved by relocating template implementations to source files, with ~2x faster builds on local benchmarks. libreanimate.so binary size was reduced through compiler and linker optimizations (-fvisibility=hidden, -ffunction-sections, -fdata-sections, -Wl,--gc-sections), decreasing runtime footprint. While no explicit major bugs are documented in this data, these changes collectively improve library compatibility, developer productivity, and end-user performance.
September 2025: Key improvements across the react-native-reanimated project focusing on API extensibility, build performance, and binary footprint. External executeSync is now available outside Bundle Mode, enabling libraries like react-native-audio-api. Build times were significantly improved by relocating template implementations to source files, with ~2x faster builds on local benchmarks. libreanimate.so binary size was reduced through compiler and linker optimizations (-fvisibility=hidden, -ffunction-sections, -fdata-sections, -Wl,--gc-sections), decreasing runtime footprint. While no explicit major bugs are documented in this data, these changes collectively improve library compatibility, developer productivity, and end-user performance.
2025-08 Monthly Summary for software-mansion/react-native-reanimated
2025-08 Monthly Summary for software-mansion/react-native-reanimated
July 2025 — Key outcomes in software-mansion/react-native-reanimated: Key features delivered: Introduced a Worklets feature flag system with dynamic flag management to decouple Worklets from core Reanimated, enabling safer experimentation and incremental rollout (commit 8c13845380bb9fc6aee8264a0ec294d835bc4f31). Major bugs fixed: Stabilized the frame loop by preventing duplicate starts and adjusted frame timing for iOS ProMotion to eliminate stutter (commits 885d356b633c5fd5d37c59e8a57df96c62c0b188; 3dd927ce8258f1459e6fbdf69e2f11bc2f4f3835). Fixed dynamic updates of layout and exiting animations when AnimatedComponent props change after mount (commit bf3a7417edf96b89ba50b78e18fec826582653ad). Codebase simplification: Removed the experimental Native View export/implementation to reduce Jest-related concerns and align with future reintroduction on a separate branch (commits a606143ab0a600ccc5ea58e7b3a224c1012c7aa1; 6128cd41d33cbd66a79e267cf89ff995f7c87c0e). Overall impact and accomplishments: Achieved smoother and more reliable animations, improved test stability, and established a safe path for feature experimentation. These changes enhance user-perceived performance, reduce flaky tests, and streamline future feature work. Technologies/skills demonstrated: iOS ProMotion optimization, frame loop timing, dynamic layout animation configuration, Worklets architecture and feature flags, codebase cleanup, and enhanced test reliability.
July 2025 — Key outcomes in software-mansion/react-native-reanimated: Key features delivered: Introduced a Worklets feature flag system with dynamic flag management to decouple Worklets from core Reanimated, enabling safer experimentation and incremental rollout (commit 8c13845380bb9fc6aee8264a0ec294d835bc4f31). Major bugs fixed: Stabilized the frame loop by preventing duplicate starts and adjusted frame timing for iOS ProMotion to eliminate stutter (commits 885d356b633c5fd5d37c59e8a57df96c62c0b188; 3dd927ce8258f1459e6fbdf69e2f11bc2f4f3835). Fixed dynamic updates of layout and exiting animations when AnimatedComponent props change after mount (commit bf3a7417edf96b89ba50b78e18fec826582653ad). Codebase simplification: Removed the experimental Native View export/implementation to reduce Jest-related concerns and align with future reintroduction on a separate branch (commits a606143ab0a600ccc5ea58e7b3a224c1012c7aa1; 6128cd41d33cbd66a79e267cf89ff995f7c87c0e). Overall impact and accomplishments: Achieved smoother and more reliable animations, improved test stability, and established a safe path for feature experimentation. These changes enhance user-perceived performance, reduce flaky tests, and streamline future feature work. Technologies/skills demonstrated: iOS ProMotion optimization, frame loop timing, dynamic layout animation configuration, Worklets architecture and feature flags, codebase cleanup, and enhanced test reliability.
June 2025 performance summary focusing on code quality, bug fixes, and cross-repo collaboration across React Native projects. Significant refactoring and cleanup in react-native-reanimated to remove legacy/duplicate code and dead code, combined with a critical bug fix in React Native's rgba() color serialization.
June 2025 performance summary focusing on code quality, bug fixes, and cross-repo collaboration across React Native projects. Significant refactoring and cleanup in react-native-reanimated to remove legacy/duplicate code and dead code, combined with a critical bug fix in React Native's rgba() color serialization.
April 2025: Implemented the Reanimated Native View Wrapper Refactor for software-mansion/react-native-reanimated. Introduced a new native view component, ReanimatedNativeView, as the initial step in refactoring createAnimatedComponent to utilize a native view wrapper with 'display: content'. The ReanimatedNativeView is exported publicly for development and testing, with plans to remove this export after the refactoring completes. This work establishes the foundation for a more maintainable architecture and sets the stage for potential rendering performance improvements.
April 2025: Implemented the Reanimated Native View Wrapper Refactor for software-mansion/react-native-reanimated. Introduced a new native view component, ReanimatedNativeView, as the initial step in refactoring createAnimatedComponent to utilize a native view wrapper with 'display: content'. The ReanimatedNativeView is exported publicly for development and testing, with plans to remove this export after the refactoring completes. This work establishes the foundation for a more maintainable architecture and sets the stage for potential rendering performance improvements.
March 2025 monthly summary for software-mansion/react-native-reanimated. Focused on unifying architecture and tightening packaging to support a clearer migration path to Reanimated v4, while ensuring build and deployment reliability for the Worklet runtime. Key activities encompassed architecture modernization and API unification, along with packaging fixes for the Worklet package to improve build integrity and deployment recognition.
March 2025 monthly summary for software-mansion/react-native-reanimated. Focused on unifying architecture and tightening packaging to support a clearer migration path to Reanimated v4, while ensuring build and deployment reliability for the Worklet runtime. Key activities encompassed architecture modernization and API unification, along with packaging fixes for the Worklet package to improve build integrity and deployment recognition.
February 2025: Delivered key features and bug fixes for react-native-reanimated across web and mobile, improving performance, maintainability, and testing capabilities. Highlights include decoupled CSS animations, restored Fabric examples, corrected animation reference handling, and removal of deprecated Shared Element Transitions across platforms.
February 2025: Delivered key features and bug fixes for react-native-reanimated across web and mobile, improving performance, maintainability, and testing capabilities. Highlights include decoupled CSS animations, restored Fabric examples, corrected animation reference handling, and removal of deprecated Shared Element Transitions across platforms.
January 2025 — Software M Mansion / react-native-reanimated: Focused architectural simplification, reliability improvements, and build compatibility to support the new architecture while improving cross-platform stability and animation quality. Key outcomes: - Architectural simplification and cleanup for the new architecture, removing REAInitializerRCTFabricSurface and streamlining cross-platform requestRender calls to remove unused parameters, enabling easier maintenance and faster integration with the updated RN runtime. Commits include b02cdb08dedc527f2569208d8d4add669729cd02 and 33f867ff4fe8d9d7863eecc4f91d693e8f60b4bf. - Animation and rendering reliability improvements: ensured Reduced Motion compliance for Fabric Layout Animations, prevented double initialization of entering animations, added null safety for maybeNativeRef in the fast path, and resolved SVG ref handling for web-based Layout Animations across DOM/React references. Key commits: 21eea19e249969da16f7ec53129b3495afbbda32; 6c55c861b94850352cefb75b83fa619e9be0d0a2; 47cc2f93fd7f6b244d31a308ac25159b17df0ac7; 18b65cb33aa05ed6c4689a90da6901e5dcee86e1. - RN and build compatibility stability: validated compatibility with React Native 0.77 for findHostInstance_DEPRECATED resolution and centralized the JS_RUNTIME_HERMES flag to Defs.h to prevent build errors. Relevant commits: 333934bcbd7f88153eda627ba040b0821b41e21a and 44a0e0d21d72e92e15d3faea30431cd240cccbb7.
January 2025 — Software M Mansion / react-native-reanimated: Focused architectural simplification, reliability improvements, and build compatibility to support the new architecture while improving cross-platform stability and animation quality. Key outcomes: - Architectural simplification and cleanup for the new architecture, removing REAInitializerRCTFabricSurface and streamlining cross-platform requestRender calls to remove unused parameters, enabling easier maintenance and faster integration with the updated RN runtime. Commits include b02cdb08dedc527f2569208d8d4add669729cd02 and 33f867ff4fe8d9d7863eecc4f91d693e8f60b4bf. - Animation and rendering reliability improvements: ensured Reduced Motion compliance for Fabric Layout Animations, prevented double initialization of entering animations, added null safety for maybeNativeRef in the fast path, and resolved SVG ref handling for web-based Layout Animations across DOM/React references. Key commits: 21eea19e249969da16f7ec53129b3495afbbda32; 6c55c861b94850352cefb75b83fa619e9be0d0a2; 47cc2f93fd7f6b244d31a308ac25159b17df0ac7; 18b65cb33aa05ed6c4689a90da6901e5dcee86e1. - RN and build compatibility stability: validated compatibility with React Native 0.77 for findHostInstance_DEPRECATED resolution and centralized the JS_RUNTIME_HERMES flag to Defs.h to prevent build errors. Relevant commits: 333934bcbd7f88153eda627ba040b0821b41e21a and 44a0e0d21d72e92e15d3faea30431cd240cccbb7.
December 2024 monthly summary focusing on key accomplishments across React Native-related repositories. Delivered core stability and performance improvements in React Native Reanimated, achieved static Hermes build compatibility for macOS, and integrated the latest Hermes across RN projects. These efforts improved animation robustness, reduced runtime overhead via worklet caching, and expanded platform support. Technologies demonstrated include advanced CMake configurations, MSVC build optimizations, and per-runtime caching strategies for worklets.
December 2024 monthly summary focusing on key accomplishments across React Native-related repositories. Delivered core stability and performance improvements in React Native Reanimated, achieved static Hermes build compatibility for macOS, and integrated the latest Hermes across RN projects. These efforts improved animation robustness, reduced runtime overhead via worklet caching, and expanded platform support. Technologies demonstrated include advanced CMake configurations, MSVC build optimizations, and per-runtime caching strategies for worklets.
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