callstack-internal/Expensify-App
Jan 2026 – Mar 2026
3 Months active
Languages Used
JavaScriptMarkdownTypeScript
Technical Skills
Form HandlingFront End DevelopmentReactReact NativeState Managementdocumentation
Michał Muzyk
PROFILE
Michał Muzyk
Over six months, Mimuzyk delivered robust features and stability improvements across Expensify/App and related repositories, focusing on reimbursement workflows, privacy-preserving data exports, and navigation enhancements. He implemented length-preserving data masking and deterministic export logic using TypeScript and JavaScript, strengthening privacy and compliance. In Expensify/App, he optimized onboarding and multi-currency flows, refactored navigation with React and React Native, and improved policy-driven logic for payments and KYC. His work included backend integration, unit testing, and code quality cleanups, resulting in more reliable, maintainable flows and increased test coverage. The depth of his contributions addressed both user experience and technical correctness.
Overall Statistics
Feature vs Bugs
55%Features
Repository Contributions
101Total
Bugs
17
Commits
101
Features
21
Lines of code
5,847
Activity Months6
Your Network
239 peopleWork History
March 2026
31 Commits • 3 Features
Mar 1, 2026March 2026 performance summary for Expensify engineering focusing on stabilizing core flows, expanding test coverage, and tightening CI/CD. Key reliability improvements were delivered across Expensify-App and Expensify/react-native-onyx, directly impacting user experience and delivery velocity. The team completed important banking flow stabilizations, navigation robustness, data handling improvements, and introduced a formal testing infrastructure, while also strengthening PR validation and CI stability to reduce regressions.
31 Commits • 3 Features
Mar 1, 2026March 2026 performance summary for Expensify engineering focusing on stabilizing core flows, expanding test coverage, and tightening CI/CD. Key reliability improvements were delivered across Expensify-App and Expensify/react-native-onyx, directly impacting user experience and delivery velocity. The team completed important banking flow stabilizations, navigation robustness, data handling improvements, and introduced a formal testing infrastructure, while also strengthening PR validation and CI stability to reduce regressions.
March 2026
February 2026
4 Commits • 2 Features
Feb 1, 2026February 2026 monthly summary for callstack-internal/Expensify-App focused on delivering robust VBBA navigation and reliable bulk payment processing. Major work included refactoring the VBBA flow to useSubPage and overhauling bulk payments to align with per-policy state and admin policies, improving correctness, flexibility, and business value.
February 2026
4 Commits • 2 Features
Feb 1, 2026February 2026 monthly summary for callstack-internal/Expensify-App focused on delivering robust VBBA navigation and reliable bulk payment processing. Major work included refactoring the VBBA flow to useSubPage and overhauling bulk payments to align with per-policy state and admin policies, improving correctness, flexibility, and business value.
January 2026
28 Commits • 6 Features
Jan 1, 2026January 2026 monthly work summary focusing on key accomplishments and business impact across Expensify/App and internal Expensify App. Delivered major reimbursement and onboarding workflow improvements, enhanced navigation and multi-step flows, currency-aligned KYC handling, and code quality gains. These changes improve user experience, reduce duplicate submissions, and strengthen policy compliance, while increasing test coverage and maintainability.
28 Commits • 6 Features
Jan 1, 2026January 2026 monthly work summary focusing on key accomplishments and business impact across Expensify/App and internal Expensify App. Delivered major reimbursement and onboarding workflow improvements, enhanced navigation and multi-step flows, currency-aligned KYC handling, and code quality gains. These changes improve user experience, reduce duplicate submissions, and strengthen policy compliance, while increasing test coverage and maintainability.
January 2026
October 2025
16 Commits • 4 Features
Oct 1, 2025During Oct 2025, delivered targeted UX and policy improvements across margelo/expensify-app-fork, focusing on reducing friction in USD reimbursement flows, clarifying VBBA state handling, standardizing director terminology, and enhancing policy/category/workspace logic for MoneyRequest and IOU flows. A dedicated code quality cleanup aligned the codebase with Prettier standards. These changes improve business value by speeding reimbursements, reducing edge-case risks, and improving compliance and maintainability.
October 2025
16 Commits • 4 Features
Oct 1, 2025During Oct 2025, delivered targeted UX and policy improvements across margelo/expensify-app-fork, focusing on reducing friction in USD reimbursement flows, clarifying VBBA state handling, standardizing director terminology, and enhancing policy/category/workspace logic for MoneyRequest and IOU flows. A dedicated code quality cleanup aligned the codebase with Prettier standards. These changes improve business value by speeding reimbursements, reducing edge-case risks, and improving compliance and maintainability.
September 2025
21 Commits • 5 Features
Sep 1, 2025September 2025 monthly summary focusing on privacy-preserving data exports, multi-currency reimbursement onboarding, currency-aware flows, and reliability improvements across Expensify/App and the forked repo. Delivered features and fixes that enhance data privacy, export determinism, onboarding for AUD/GBP/EUR, currency-aware payment and wallet flows, and Onyx stability with robust error handling and maintainability enhancements.
21 Commits • 5 Features
Sep 1, 2025September 2025 monthly summary focusing on privacy-preserving data exports, multi-currency reimbursement onboarding, currency-aware flows, and reliability improvements across Expensify/App and the forked repo. Delivered features and fixes that enhance data privacy, export determinism, onboarding for AUD/GBP/EUR, currency-aware payment and wallet flows, and Onyx stability with robust error handling and maintainability enhancements.
September 2025
October 2024
1 Commits • 1 Features
Oct 1, 2024Concise monthly summary for 2024-10 focused on Expensify/expensify-common contributions.
October 2024
1 Commits • 1 Features
Oct 1, 2024Concise monthly summary for 2024-10 focused on Expensify/expensify-common contributions.
Activity
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Quality Metrics
Correctness89.2%
Maintainability86.0%
Architecture83.0%
Performance84.8%
AI Usage23.4%
Skills & Technologies
Programming Languages
JavaScriptMarkdownShellTypeScriptYAML
Technical Skills
API IntegrationAPI integrationBackend DevelopmentCode RefactoringConstants ManagementContinuous IntegrationCustom HooksData MaskingData StructuringDatabase InteractionDebuggingDevOpsDocumentationError HandlingForm Handling
Repositories Contributed To
Overview of all repositories you've contributed to across your timeline
margelo/expensify-app-fork
Sep 2025 – Oct 2025
2 Months active
Languages Used
JavaScriptTypeScript
Technical Skills
API IntegrationBackend DevelopmentDatabase InteractionDebuggingError HandlingForm Handling
Expensify/App
Sep 2025 – Jan 2026
2 Months active
Languages Used
TypeScriptJavaScriptMarkdown
Technical Skills
Data MaskingJavaScriptRefactoringSecurityTypeScriptAPI integration
Expensify/react-native-onyx
Mar 2026 – Mar 2026
1 Month active
Languages Used
JavaScriptShellTypeScriptYAML
Technical Skills
Continuous IntegrationDevOpsGitHub ActionsJavaScript DevelopmentShell ScriptingTypeScript
Expensify/expensify-common
Oct 2024 – Oct 2024
1 Month active
Languages Used
TypeScript
Technical Skills
Constants ManagementData Structuring