Tomasz Zawadzki engineered core features and stability improvements for the Expensify/react-native-live-markdown and mrousavy/react-native-reanimated repositories, focusing on cross-platform React Native architecture. He refactored markdown parsing and rendering pipelines, introduced custom parser support, and modernized build systems using C++, TypeScript, and Objective-C. His work included upgrading dependencies, consolidating build scripts, and enhancing CI/CD reliability, which improved onboarding and reduced technical debt. Tomasz also implemented performance optimizations for animation and text input, streamlined error handling, and clarified documentation. His contributions demonstrated deep architectural understanding, resulting in maintainable, robust codebases that support evolving React Native and mobile development requirements.
October 2025 monthly summary focusing on key features delivered, major fixes, and overall impact across rainbow and reanimated repositories. Implemented refactor and performance improvements that enhance maintainability and user experience, with cross-repo collaboration and practical UI performance optimizations.
October 2025 monthly summary focusing on key features delivered, major fixes, and overall impact across rainbow and reanimated repositories. Implemented refactor and performance improvements that enhance maintainability and user experience, with cross-repo collaboration and practical UI performance optimizations.
September 2025 monthly summary focusing on two repositories: mrousavy/react-native-reanimated and Expensify/react-native-live-markdown. Delivered work strengthened build reliability, clarified documentation, and improved developer experience for React Native and Expo users.
September 2025 monthly summary focusing on two repositories: mrousavy/react-native-reanimated and Expensify/react-native-live-markdown. Delivered work strengthened build reliability, clarified documentation, and improved developer experience for React Native and Expo users.
August 2025 monthly highlights for mrousavy/react-native-reanimated. Delivered substantial Android fast-path enhancements and broader synchronous props support, added a bottom-sheet example with migration docs, refreshed core examples and demos (FPS, filter), and completed critical maintenance and documentation work to improve stability, build reliability, and developer experience. These changes reduce runtime errors, simplify adoption of new features, and accelerate platform parity across Android and iOS.
August 2025 monthly highlights for mrousavy/react-native-reanimated. Delivered substantial Android fast-path enhancements and broader synchronous props support, added a bottom-sheet example with migration docs, refreshed core examples and demos (FPS, filter), and completed critical maintenance and documentation work to improve stability, build reliability, and developer experience. These changes reduce runtime errors, simplify adoption of new features, and accelerate platform parity across Android and iOS.
July 2025 focused on stability, migration readiness, and developer experience across the Reanimated suite, React Native core, and the live-markdown project. Delivered API deprecation notices and a name refactor to improve clarity and future-proofing; hardened the build system and Android error handling to reduce build-time failures; and expanded migration/docs guidance to streamline upgrades to 4.x. These efforts reduce maintenance overhead, accelerate onboarding for adopters, and demonstrate strong cross-repo collaboration and platform-level improvements.
July 2025 focused on stability, migration readiness, and developer experience across the Reanimated suite, React Native core, and the live-markdown project. Delivered API deprecation notices and a name refactor to improve clarity and future-proofing; hardened the build system and Android error handling to reduce build-time failures; and expanded migration/docs guidance to streamline upgrades to 4.x. These efforts reduce maintenance overhead, accelerate onboarding for adopters, and demonstrate strong cross-repo collaboration and platform-level improvements.
June 2025 monthly summary: Delivered impactful upgrades, API modernization, and runtime simplifications across two repositories, driving stability, performance, and developer experience. Key outcomes include upgrading to React Native 0.80.0-rc.4 across core and fabric-example to unlock latest improvements, introducing a per-component JS props API with registerJSProps, pausing Reanimated commits to prevent React-origin starvation and improve frame scheduling, removing the V8 runtime integration and rnRuntime argument to simplify runtime maintenance, and modernizing native code paths with improved error reporting and C++20 contains. Additionally, the Expensify live-markdown example gained an Input Mode Visualization feature, improving user guidance and reducing configuration confusion.
June 2025 monthly summary: Delivered impactful upgrades, API modernization, and runtime simplifications across two repositories, driving stability, performance, and developer experience. Key outcomes include upgrading to React Native 0.80.0-rc.4 across core and fabric-example to unlock latest improvements, introducing a per-component JS props API with registerJSProps, pausing Reanimated commits to prevent React-origin starvation and improve frame scheduling, removing the V8 runtime integration and rnRuntime argument to simplify runtime maintenance, and modernizing native code paths with improved error reporting and C++20 contains. Additionally, the Expensify live-markdown example gained an Input Mode Visualization feature, improving user guidance and reducing configuration confusion.
May 2025 focused on upgrade readiness, platform stability, and developer experience across major React Native ecosystems. Delivered compatibility updates for React Native 0.80 in Reanimated, stabilized core platform initialization, advanced Worklets integration with platform-agnostic installation, introduced a new animation example demonstrating opacity, transform, and grid animations, and expanded troubleshooting/docs to cover tvOS and visionOS. These efforts reduce upgrade risk for customers, improve build reliability on iOS/Android, and demonstrate tangible cross-platform performance and architectural improvements.
May 2025 focused on upgrade readiness, platform stability, and developer experience across major React Native ecosystems. Delivered compatibility updates for React Native 0.80 in Reanimated, stabilized core platform initialization, advanced Worklets integration with platform-agnostic installation, introduced a new animation example demonstrating opacity, transform, and grid animations, and expanded troubleshooting/docs to cover tvOS and visionOS. These efforts reduce upgrade risk for customers, improve build reliability on iOS/Android, and demonstrate tangible cross-platform performance and architectural improvements.
April 2025 monthly summary: Delivered key enhancements across two major React Native repos, focusing on compatibility, build stability, and developer experience. Upgraded example apps to React Native 0.79.x for both Expensify/react-native-live-markdown and software-mansion/react-native-reanimated, ensuring alignment with RN 0.79.x changes. Improved Markdown parsing robustness (blockquotes, links, mentions) and updated dependencies (RNLiveMarkdown 0.1.270, Yoga hash). Fixed iOS paste handling for Markdown input by correcting the selector invocation. Consolidated Android build configuration by merging CMakeLists.txt files, and migrated Babel config to react-native-worklets/plugin. Standardized code naming and podspec naming, and centralized CI/CD token usage for nightly builds. These changes reduce maintenance burden, improve upgrade readiness, and enhance developer and end-user experience.
April 2025 monthly summary: Delivered key enhancements across two major React Native repos, focusing on compatibility, build stability, and developer experience. Upgraded example apps to React Native 0.79.x for both Expensify/react-native-live-markdown and software-mansion/react-native-reanimated, ensuring alignment with RN 0.79.x changes. Improved Markdown parsing robustness (blockquotes, links, mentions) and updated dependencies (RNLiveMarkdown 0.1.270, Yoga hash). Fixed iOS paste handling for Markdown input by correcting the selector invocation. Consolidated Android build configuration by merging CMakeLists.txt files, and migrated Babel config to react-native-worklets/plugin. Standardized code naming and podspec naming, and centralized CI/CD token usage for nightly builds. These changes reduce maintenance burden, improve upgrade readiness, and enhance developer and end-user experience.
March 2025 performance highlights across react-native-reanimated and Expensify/react-native-live-markdown focused on architectural refactors, initialization stability, and Worklets branding. Key outcomes include streamlined iOS/Android init flows, modularization and cleaner wiring of runtime and UIManager interactions, and targeted code cleanup to reduce risk and enable faster iteration.
March 2025 performance highlights across react-native-reanimated and Expensify/react-native-live-markdown focused on architectural refactors, initialization stability, and Worklets branding. Key outcomes include streamlined iOS/Android init flows, modularization and cleaner wiring of runtime and UIManager interactions, and targeted code cleanup to reduce risk and enable faster iteration.
February 2025 performance summary: Delivered stability-focused enhancements and architectural cleanups across three repos, resulting in stronger reliability, improved type safety, and streamlined build processes. Key features were shipped, critical bugs fixed, and cross-repo refactoring advanced maintainability and developer velocity across iOS/Android and RN worklets. Key achievements (highlights across repos): - Expensify/react-native-live-markdown: Dependency management and CI/tooling stability updates to improve stability and security; type safety improvements by replacing generic Range with MarkdownRange and aligning docs. - software-mansion/react-native-reanimated: Podspec/Gradle build cleanups; Worklet Runtime enhancements including enabling supportsLocking and runtime refactor; ESLint plugin update; Android Fabric example build-from-source guidance; extensive architecture/API cleanup; major refactors and removal of obsolete code paths; bug fix to restore canOverrideExistingModule default behavior; NativeProxy consolidation and UIManagerReanimatedHelper removal. - mrousavy/expo: Expo Android plugin typo fix in applyLinterOptions to ensure correct linting options during builds. Overall impact: Reduced risk from outdated tooling and complex build scripts, improved type contracts and compatibility across platforms, and a leaner codebase with clearer architectures. These changes enable faster iteration, more reliable builds, and stronger security posture. Technologies/skills demonstrated: TypeScript type improvements; CI/CD modernization (GitHub Actions v4, Node.js 20); Gradle/podspec modernization; runtime architecture refactor; ESLint rule alignment; cross-repo coordination and documentation updates.
February 2025 performance summary: Delivered stability-focused enhancements and architectural cleanups across three repos, resulting in stronger reliability, improved type safety, and streamlined build processes. Key features were shipped, critical bugs fixed, and cross-repo refactoring advanced maintainability and developer velocity across iOS/Android and RN worklets. Key achievements (highlights across repos): - Expensify/react-native-live-markdown: Dependency management and CI/tooling stability updates to improve stability and security; type safety improvements by replacing generic Range with MarkdownRange and aligning docs. - software-mansion/react-native-reanimated: Podspec/Gradle build cleanups; Worklet Runtime enhancements including enabling supportsLocking and runtime refactor; ESLint plugin update; Android Fabric example build-from-source guidance; extensive architecture/API cleanup; major refactors and removal of obsolete code paths; bug fix to restore canOverrideExistingModule default behavior; NativeProxy consolidation and UIManagerReanimatedHelper removal. - mrousavy/expo: Expo Android plugin typo fix in applyLinterOptions to ensure correct linting options during builds. Overall impact: Reduced risk from outdated tooling and complex build scripts, improved type contracts and compatibility across platforms, and a leaner codebase with clearer architectures. These changes enable faster iteration, more reliable builds, and stronger security posture. Technologies/skills demonstrated: TypeScript type improvements; CI/CD modernization (GitHub Actions v4, Node.js 20); Gradle/podspec modernization; runtime architecture refactor; ESLint rule alignment; cross-repo coordination and documentation updates.
January 2025 (2025-01) Monthly summary for Expensify/react-native-live-markdown. Delivered critical enhancements to expose and stabilize the Markdown Worklet runtime, improved editor UX for MarkdownTextInputDecoratorView, and strengthened overall build quality and maintainability across the repository. These efforts enable external code to interact with the worklet runtime, reduce editing disruptions, and improve cross-platform robustness with safer code paths.
January 2025 (2025-01) Monthly summary for Expensify/react-native-live-markdown. Delivered critical enhancements to expose and stabilize the Markdown Worklet runtime, improved editor UX for MarkdownTextInputDecoratorView, and strengthened overall build quality and maintainability across the repository. These efforts enable external code to interact with the worklet runtime, reduce editing disruptions, and improve cross-platform robustness with safer code paths.
December 2024 monthly summary for Expensify/react-native-live-markdown. The team delivered a major architectural refactor of the Markdown parsing/rendering pipeline, introduced custom parsing capabilities, stabilized the release build, and incrementally hardened cross-platform code with instrumentation and quality improvements. The work drove concrete business value by enabling flexible, user-defined markdown rendering, improving release reliability, and reducing platform-specific divergence. Key results and business value: - Cross-platform Markdown rendering architecture overhaul completed, standardizing parsing, formatting, and range handling with dedicated MarkdownParser, MarkdownFormatter, and MarkdownRange, enabling easier maintenance and extensibility across iOS and Android. - Custom parsing support for MarkdownTextInput added via a parser prop, enabling user-defined worklets to customize markdown rendering (feature delivered; aligns with customer customization needs). - Release stability improvements: Hermes path corrected and RNLiveMarkdown dependency update corrected in Podfile.lock, addressing release build failures and CI reliability. - Build and quality hardening: updated to React Native Reanimated 3.16.4, added static framework build fixes, added systraces on Android, and introduced nullability annotations and better error handling for edge cases (e.g., html-entities not workletized). - Engineering impact: centralized parsing/formatting logic improves testability, cross-platform consistency, and performance instrumentation across iOS/Android, reducing future technical debt and simplifying onboarding for new contributors. Top 3-5 achievements: - Custom MarkdownTextInput parsing support implemented (commit: 0c283b539bba92af47159cce70ca07b240b7c938). - Architecture overhaul introducing MarkdownParser, MarkdownFormatter, MarkdownRange; multi-platform refactor and shared library relocation (commits include 14e59f1d..., c0dbced7..., 02793be5..., 790c02c6..., and more). - Release build bug fix for Hermes path and Podfile.lock dependency alignment (commit: 2afdb1fe3d8f45558dac3a6e1791f963f5014341). - Build stability and quality enhancements (RN Reanimated bump to 3.16.4, static framework fixes, Android systrace, and code quality improvements). - Cross-platform consistency and performance instrumentation across iOS/Android during the refactor (numerous commits across the overhaul).
December 2024 monthly summary for Expensify/react-native-live-markdown. The team delivered a major architectural refactor of the Markdown parsing/rendering pipeline, introduced custom parsing capabilities, stabilized the release build, and incrementally hardened cross-platform code with instrumentation and quality improvements. The work drove concrete business value by enabling flexible, user-defined markdown rendering, improving release reliability, and reducing platform-specific divergence. Key results and business value: - Cross-platform Markdown rendering architecture overhaul completed, standardizing parsing, formatting, and range handling with dedicated MarkdownParser, MarkdownFormatter, and MarkdownRange, enabling easier maintenance and extensibility across iOS and Android. - Custom parsing support for MarkdownTextInput added via a parser prop, enabling user-defined worklets to customize markdown rendering (feature delivered; aligns with customer customization needs). - Release stability improvements: Hermes path corrected and RNLiveMarkdown dependency update corrected in Podfile.lock, addressing release build failures and CI reliability. - Build and quality hardening: updated to React Native Reanimated 3.16.4, added static framework build fixes, added systraces on Android, and introduced nullability annotations and better error handling for edge cases (e.g., html-entities not workletized). - Engineering impact: centralized parsing/formatting logic improves testability, cross-platform consistency, and performance instrumentation across iOS/Android, reducing future technical debt and simplifying onboarding for new contributors. Top 3-5 achievements: - Custom MarkdownTextInput parsing support implemented (commit: 0c283b539bba92af47159cce70ca07b240b7c938). - Architecture overhaul introducing MarkdownParser, MarkdownFormatter, MarkdownRange; multi-platform refactor and shared library relocation (commits include 14e59f1d..., c0dbced7..., 02793be5..., 790c02c6..., and more). - Release build bug fix for Hermes path and Podfile.lock dependency alignment (commit: 2afdb1fe3d8f45558dac3a6e1791f963f5014341). - Build stability and quality enhancements (RN Reanimated bump to 3.16.4, static framework fixes, Android systrace, and code quality improvements). - Cross-platform consistency and performance instrumentation across iOS/Android during the refactor (numerous commits across the overhaul).
November 2024 monthly summary for Expensify/react-native-live-markdown, software-mansion/react-native-reanimated, and software-mansion/react-native-gesture-handler. Focused on stabilizing builds, fixing CI issues, improving docs, and future-proofing Android configurations. Result: fewer build failures, faster CI, clearer onboarding, and stronger cross-repo compatibility.
November 2024 monthly summary for Expensify/react-native-live-markdown, software-mansion/react-native-reanimated, and software-mansion/react-native-gesture-handler. Focused on stabilizing builds, fixing CI issues, improving docs, and future-proofing Android configurations. Result: fewer build failures, faster CI, clearer onboarding, and stronger cross-repo compatibility.
October 2024 monthly summary for Expensify/react-native-live-markdown focused on stability, maintainability, and supporting future feature delivery. No user-facing features shipped this month; primary work consisted of Android build reliability improvements and lint-related stability enhancements to streamline development and CI pipelines.
October 2024 monthly summary for Expensify/react-native-live-markdown focused on stability, maintainability, and supporting future feature delivery. No user-facing features shipped this month; primary work consisted of Android build reliability improvements and lint-related stability enhancements to streamline development and CI pipelines.
Overview of all repositories you've contributed to across your timeline