mbta/dotcom
Nov 2024 – May 2026
19 Months active
Languages Used
BashDockerfileElixirHTMLJSONJavaScriptMarkdownSCSS
Technical Skills
API DevelopmentAccessibilityBackend DevelopmentCI/CDCode CleanupCode Refactoring
Cristen Jones
PROFILE
Cristen Jones
Over 19 months, contributed to mbta/dotcom by building and refining features that improved transit schedule accuracy, trip planning, and user experience. Delivered enhancements such as real-time schedule finders, internationalization, and robust alert systems, while modernizing the frontend with Phoenix LiveView and React. Applied Elixir and TypeScript to implement backend data integrations, optimize CI/CD pipelines, and streamline UI components for accessibility and reliability. Addressed edge cases in schedule deduplication, improved caching strategies, and upgraded dependencies to maintain security and performance. The work emphasized maintainability, test coverage, and data integrity, resulting in a more stable and user-friendly transit platform.
Overall Statistics
Feature vs Bugs
64%Features
Repository Contributions
311Total
Bugs
80
Commits
311
Features
141
Lines of code
99,436
Activity Months19
Your Network
37 peopleWork History
May 2026
9 Commits • 2 Features
May 1, 2026May 2026 for mbta/dotcom focused on delivering reliable user-facing features while strengthening stability and security. Key work on Schedule Finder improved reliability and performance, with live view error handling and optimized on-mount service fetching. The Trip Planner UI was updated to correctly represent the Mattapan shuttle through color-coding improvements. Behind the scenes, stability and security were enhanced via dependency upgrades, Bandit adapter integration, targeted test fixes, and safeguards including rollback planning to maintain system reliability.
9 Commits • 2 Features
May 1, 2026May 2026 for mbta/dotcom focused on delivering reliable user-facing features while strengthening stability and security. Key work on Schedule Finder improved reliability and performance, with live view error handling and optimized on-mount service fetching. The Trip Planner UI was updated to correctly represent the Mattapan shuttle through color-coding improvements. Behind the scenes, stability and security were enhanced via dependency upgrades, Bandit adapter integration, targeted test fixes, and safeguards including rollback planning to maintain system reliability.
May 2026
April 2026
11 Commits • 5 Features
Apr 1, 2026April 2026 monthly summary for mbta/dotcom: Delivered key features improving reliability and UX of ScheduleFinderLive, normalized teaser image URLs, added rail-replacement-bus visuals and naming, and extended timetable coverage with Long Wharf boat stops. Fixed a critical navigation bug by correcting broken schedule view links and reverting the CR-Foxboro button rendering. Also removed Sentry integration to streamline dependencies, reducing maintenance burden. This work enhances schedule accuracy, reduces user confusion, and improves data freshness with visibility-based refresh and nil-safe last_trip_time checks. Technologies/skills demonstrated include Phoenix LiveView reliability patterns, rewrite_url/1 usage, visibilitychange integration, and test-driven development.
April 2026
11 Commits • 5 Features
Apr 1, 2026April 2026 monthly summary for mbta/dotcom: Delivered key features improving reliability and UX of ScheduleFinderLive, normalized teaser image URLs, added rail-replacement-bus visuals and naming, and extended timetable coverage with Long Wharf boat stops. Fixed a critical navigation bug by correcting broken schedule view links and reverting the CR-Foxboro button rendering. Also removed Sentry integration to streamline dependencies, reducing maintenance burden. This work enhances schedule accuracy, reduces user confusion, and improves data freshness with visibility-based refresh and nil-safe last_trip_time checks. Technologies/skills demonstrated include Phoenix LiveView reliability patterns, rewrite_url/1 usage, visibilitychange integration, and test-driven development.
March 2026
18 Commits • 9 Features
Mar 1, 2026March 2026 was a focused delivery cycle for mbta/dotcom, delivering user-facing timetable enhancements, reliability improvements, and stronger test/CI practices. The work reduced runtime errors, improved data handling, and delivered new capabilities across timetable and schedule tooling, while strengthening performance and developer productivity through testing, static analysis, and modern module patterns.
18 Commits • 9 Features
Mar 1, 2026March 2026 was a focused delivery cycle for mbta/dotcom, delivering user-facing timetable enhancements, reliability improvements, and stronger test/CI practices. The work reduced runtime errors, improved data handling, and delivered new capabilities across timetable and schedule tooling, while strengthening performance and developer productivity through testing, static analysis, and modern module patterns.
March 2026
February 2026
10 Commits • 6 Features
Feb 1, 2026February 2026 monthly performance summary for mbta/dotcom: Delivered high-impact features and reliability improvements across real-time scheduling, event timetables, and accessibility, directly enhancing rider trust and operational efficiency. Key features include vehicle data access by ID with status-aware arrival predictions and a World Cup timetable live view with match-specific boarding groups and time tables. Also delivered accuracy enhancements for Upcoming Departures by excluding past skipped or canceled schedules and improved Trip Details by removing predictions for already-visited stops. Additional polish and stability work covered accessibility enhancements (calendar button title) and infrastructure improvements (memory provisioning, updated load-testing scripts, and targeted refactors) to support reliability and performance. Overall impact: clearer departure displays, more accurate predictions, robust event support, and better testing and deployment readiness—driving higher user satisfaction and reduced support overhead. Technologies/skills demonstrated: backend data integration and status handling, real-time prediction logic, front-end live views, comprehensive test coverage, performance optimization, and accessibility improvements.
February 2026
10 Commits • 6 Features
Feb 1, 2026February 2026 monthly performance summary for mbta/dotcom: Delivered high-impact features and reliability improvements across real-time scheduling, event timetables, and accessibility, directly enhancing rider trust and operational efficiency. Key features include vehicle data access by ID with status-aware arrival predictions and a World Cup timetable live view with match-specific boarding groups and time tables. Also delivered accuracy enhancements for Upcoming Departures by excluding past skipped or canceled schedules and improved Trip Details by removing predictions for already-visited stops. Additional polish and stability work covered accessibility enhancements (calendar button title) and infrastructure improvements (memory provisioning, updated load-testing scripts, and targeted refactors) to support reliability and performance. Overall impact: clearer departure displays, more accurate predictions, robust event support, and better testing and deployment readiness—driving higher user satisfaction and reduced support overhead. Technologies/skills demonstrated: backend data integration and status handling, real-time prediction logic, front-end live views, comprehensive test coverage, performance optimization, and accessibility improvements.
January 2026
30 Commits • 20 Features
Jan 1, 2026January 2026 (mbta/dotcom) — Focused on reliability, UX, and performance improvements across the dotcom platform. Delivered data integrity enhancements, UI refinements, and framework upgrades while hardening CI/test reliability. Key features delivered: - Time library migration: Timex to Date for time handling (commit 62e47409e05d748f0d8b640e5e34a2031473ae8e). Added tests for all_valid_dates_for_service/1. - Schedule Finder Live: services picker UI implemented (commit 56fda44270f81213dd22424aebb8efbcbe9aff85). - Schedules.Schedule: record schedule ID to ensure identity (commit 5137bbf91bbcf77729a8ed6a424f029bc31a5a36). - Framework upgrades: Elixir/Erlang/Phoenix updated (commit c92c94db6182e21494717649ac3ce45df3f4f7f8). - SF2.0: Show vehicle crowding data (commit ef344044bb90d41482c0ee25dd5bb23495fa5eec). - Playwright improvements (commit 10067ddbb01db1fd7177cc08617c99eb88c71129). Major bugs fixed: - Hotfix: LineController.ServicePatterns (commit b2ec5f94611c68734e7bfe216981e286c9ce8558). - ScheduleFinder: get stop platform name (commit 51359bafd27839762f9e66526e2347a25ba7360a). - ScheduleFinderLive: use departure route (commit 01bebed2f622e7b55ff850b87bbbed551b88fe26). - SF2.0/UpcomingDepartures: show no realtime (commit a1940c00bdc74be661d532a96e078093f5b5617f). - CI: Correct merged section name for Asana task (commit 39c2d27e511485364a3481fdb0ff8704a778b879). Overall impact and accomplishments: - Increased system reliability, faster releases, and better user experience through code quality improvements, data integrity upgrades, and CI/test hygiene. The upgrades position the product for upcoming features with stronger performance and stability. Technologies/skills demonstrated: - Elixir/Erlang/Phoenix upgrades and runtime configuration. - UI/UX refinements with Tailwind; services picker and responsive components. - Test automation and reliability via Playwright improvements. - Data integrity enhancements (recording schedule IDs) and robust time handling (Date-based time library). - CI/CD improvements and code refactoring patterns.
30 Commits • 20 Features
Jan 1, 2026January 2026 (mbta/dotcom) — Focused on reliability, UX, and performance improvements across the dotcom platform. Delivered data integrity enhancements, UI refinements, and framework upgrades while hardening CI/test reliability. Key features delivered: - Time library migration: Timex to Date for time handling (commit 62e47409e05d748f0d8b640e5e34a2031473ae8e). Added tests for all_valid_dates_for_service/1. - Schedule Finder Live: services picker UI implemented (commit 56fda44270f81213dd22424aebb8efbcbe9aff85). - Schedules.Schedule: record schedule ID to ensure identity (commit 5137bbf91bbcf77729a8ed6a424f029bc31a5a36). - Framework upgrades: Elixir/Erlang/Phoenix updated (commit c92c94db6182e21494717649ac3ce45df3f4f7f8). - SF2.0: Show vehicle crowding data (commit ef344044bb90d41482c0ee25dd5bb23495fa5eec). - Playwright improvements (commit 10067ddbb01db1fd7177cc08617c99eb88c71129). Major bugs fixed: - Hotfix: LineController.ServicePatterns (commit b2ec5f94611c68734e7bfe216981e286c9ce8558). - ScheduleFinder: get stop platform name (commit 51359bafd27839762f9e66526e2347a25ba7360a). - ScheduleFinderLive: use departure route (commit 01bebed2f622e7b55ff850b87bbbed551b88fe26). - SF2.0/UpcomingDepartures: show no realtime (commit a1940c00bdc74be661d532a96e078093f5b5617f). - CI: Correct merged section name for Asana task (commit 39c2d27e511485364a3481fdb0ff8704a778b879). Overall impact and accomplishments: - Increased system reliability, faster releases, and better user experience through code quality improvements, data integrity upgrades, and CI/test hygiene. The upgrades position the product for upcoming features with stronger performance and stability. Technologies/skills demonstrated: - Elixir/Erlang/Phoenix upgrades and runtime configuration. - UI/UX refinements with Tailwind; services picker and responsive components. - Test automation and reliability via Playwright improvements. - Data integrity enhancements (recording schedule IDs) and robust time handling (Date-based time library). - CI/CD improvements and code refactoring patterns.
January 2026
December 2025
9 Commits • 2 Features
Dec 1, 2025Delivered major Schedule Finder enhancements for mbta/dotcom in 2025-12, including Daily Schedule Finder and Route Display Enhancements (ScheduleFinder2.0) with daily departures/arrivals, direction-aware routing links, a new route diagram UI, service availability filtering, real-time service alerts, and an integrated alert system in ScheduleFinderLive. Also delivered current-alerts flow, default service date support, and comprehensive route display improvements via RouteComponents (lined_list with diagram) and tests. UI polish included Timetable Icon improvements for access and parking icons to improve visibility and brand consistency. Implemented caching strategy changes (temporary cache directory and removal of HTTP caching for external data) to improve data freshness and reliability. Added service-availability correctness refinements by excluding no-school services in LineController, improving today’s service status accuracy.
December 2025
9 Commits • 2 Features
Dec 1, 2025Delivered major Schedule Finder enhancements for mbta/dotcom in 2025-12, including Daily Schedule Finder and Route Display Enhancements (ScheduleFinder2.0) with daily departures/arrivals, direction-aware routing links, a new route diagram UI, service availability filtering, real-time service alerts, and an integrated alert system in ScheduleFinderLive. Also delivered current-alerts flow, default service date support, and comprehensive route display improvements via RouteComponents (lined_list with diagram) and tests. UI polish included Timetable Icon improvements for access and parking icons to improve visibility and brand consistency. Implemented caching strategy changes (temporary cache directory and removal of HTTP caching for external data) to improve data freshness and reliability. Added service-availability correctness refinements by excluding no-school services in LineController, improving today’s service status accuracy.
November 2025
1 Commits
Nov 1, 2025November 2025: Key work on mbta/dotcom focused on correctness of transit schedule data. Delivered a targeted edge-case fix to schedule deduplication to ensure Friday services don't conflict with overlapping weekday schedules, improving accuracy of displayed transit information and reducing misleading listings. The fix stabilizes user-facing schedule data and reduces potential support queries related to incorrect service listings.
1 Commits
Nov 1, 2025November 2025: Key work on mbta/dotcom focused on correctness of transit schedule data. Delivered a targeted edge-case fix to schedule deduplication to ensure Friday services don't conflict with overlapping weekday schedules, improving accuracy of displayed transit information and reducing misleading listings. The fix stabilizes user-facing schedule data and reduces potential support queries related to incorrect service listings.
November 2025
October 2025
16 Commits • 6 Features
Oct 1, 2025October 2025 performance snapshot for mbta/dotcom: Delivered a mix of user-facing features, reliability fixes, and platform improvements that enhance search, trip planning, and overall responsiveness, while modernizing the codebase for maintainability and future velocity.
October 2025
16 Commits • 6 Features
Oct 1, 2025October 2025 performance snapshot for mbta/dotcom: Delivered a mix of user-facing features, reliability fixes, and platform improvements that enhance search, trip planning, and overall responsiveness, while modernizing the codebase for maintainability and future velocity.
September 2025
7 Commits • 3 Features
Sep 1, 2025September 2025 — mbta/dotcom delivered tangible business value through localization readiness, UX improvements, and stronger code quality. Key features delivered: Trip Planner internationalization and centralized breadcrumbs via a new hook with translations updated; UI/UX enhancements including clickable alert links and a Commuter Rail survey banner. Major stability and quality improvements: i18n/breadcrumb refactor, TypeScript fix, and refined interline merging logic, plus a formatting migration to standardize code style. Notable bug fix: corrected formatting of the alerts more-info link. Overall impact: improved localization readiness, better user engagement, and a more maintainable codebase with faster integration cycles.
7 Commits • 3 Features
Sep 1, 2025September 2025 — mbta/dotcom delivered tangible business value through localization readiness, UX improvements, and stronger code quality. Key features delivered: Trip Planner internationalization and centralized breadcrumbs via a new hook with translations updated; UI/UX enhancements including clickable alert links and a Commuter Rail survey banner. Major stability and quality improvements: i18n/breadcrumb refactor, TypeScript fix, and refined interline merging logic, plus a formatting migration to standardize code style. Notable bug fix: corrected formatting of the alerts more-info link. Overall impact: improved localization readiness, better user engagement, and a more maintainable codebase with faster integration cycles.
September 2025
August 2025
14 Commits • 3 Features
Aug 1, 2025Performance-focused monthly summary for 2025-08 covering mbta/dotcom. Delivered major features and fixes across internationalization/localization, trip planning reliability, display/alerts corrections, and CMS/Algolia integration. These initiatives improved accessibility and localization across locales, trip planning stability and error handling, content integration, and search capabilities, delivering measurable business value through enhanced user experience and platform robustness.
August 2025
14 Commits • 3 Features
Aug 1, 2025Performance-focused monthly summary for 2025-08 covering mbta/dotcom. Delivered major features and fixes across internationalization/localization, trip planning reliability, display/alerts corrections, and CMS/Algolia integration. These initiatives improved accessibility and localization across locales, trip planning stability and error handling, content integration, and search capabilities, delivering measurable business value through enhanced user experience and platform robustness.
July 2025
18 Commits • 11 Features
Jul 1, 2025July 2025 monthly summary for mbta/dotcom. Delivered a set of UX, reliability, and stability improvements across Trip Planner, location search, alerts accuracy, and localization, with a strong emphasis on business value, user trust, and maintainability.
18 Commits • 11 Features
Jul 1, 2025July 2025 monthly summary for mbta/dotcom. Delivered a set of UX, reliability, and stability improvements across Trip Planner, location search, alerts accuracy, and localization, with a strong emphasis on business value, user trust, and maintainability.
July 2025
June 2025
16 Commits • 11 Features
Jun 1, 2025June 2025 highlights across mbta/dotcom focusing on data reliability, accessibility, UX simplification, and CI/CD improvements. Delivered CSV-based timetable loading for F6/F7/F8 with a new TimetableLoader and updated UI, upgraded accessibility libraries, introduced track changes and parking_closure alerts, streamlined search by removing location search, and modernized Trip Planner frontend. Architectural cleanups reduced maintenance overhead and improved security and test reliability.
June 2025
16 Commits • 11 Features
Jun 1, 2025June 2025 highlights across mbta/dotcom focusing on data reliability, accessibility, UX simplification, and CI/CD improvements. Delivered CSV-based timetable loading for F6/F7/F8 with a new TimetableLoader and updated UI, upgraded accessibility libraries, introduced track changes and parking_closure alerts, streamlined search by removing location search, and modernized Trip Planner frontend. Architectural cleanups reduced maintenance overhead and improved security and test reliability.
May 2025
15 Commits • 5 Features
May 1, 2025May 2025 performance summary for mbta/dotcom: Delivered focused features, fixed critical issues, and strengthened observability and CI/CD, driving reliability and business value across schedules, trips, and search.
15 Commits • 5 Features
May 1, 2025May 2025 performance summary for mbta/dotcom: Delivered focused features, fixed critical issues, and strengthened observability and CI/CD, driving reliability and business value across schedules, trips, and search.
May 2025
April 2025
23 Commits • 13 Features
Apr 1, 2025April 2025 monthly summary for mbta/dotcom focusing on delivering key features, fixing critical bugs, and improving performance, accessibility, and design consistency. Highlights include reliability improvements through URL handling refactor, broader schedule coverage with shuttle stops, and significant UI and design system updates, along with cleanup of deprecated trip planner code and monitoring enhancements.
April 2025
23 Commits • 13 Features
Apr 1, 2025April 2025 monthly summary for mbta/dotcom focusing on delivering key features, fixing critical bugs, and improving performance, accessibility, and design consistency. Highlights include reliability improvements through URL handling refactor, broader schedule coverage with shuttle stops, and significant UI and design system updates, along with cleanup of deprecated trip planner code and monitoring enhancements.
March 2025
30 Commits • 11 Features
Mar 1, 2025March 2025 mbta/dotcom monthly summary focusing on key accomplishments, major bugs fixed, and overall impact. The month delivered security hardening for frontend assets, enhancements and cleanup in the Timetable Controller, migration of templates to .heex, and CI/CD and dependency upgrades, along with performance and reliability improvements across predictions and schedule processing. These changes improved security posture, UI simplicity, reliability of timetable and predictions, and developer productivity through streamlined CI/CD and testing. Top 3-5 achievements highlight how business value and technical excellence were delivered this month across the repository mbta/dotcom.
30 Commits • 11 Features
Mar 1, 2025March 2025 mbta/dotcom monthly summary focusing on key accomplishments, major bugs fixed, and overall impact. The month delivered security hardening for frontend assets, enhancements and cleanup in the Timetable Controller, migration of templates to .heex, and CI/CD and dependency upgrades, along with performance and reliability improvements across predictions and schedule processing. These changes improved security posture, UI simplicity, reliability of timetable and predictions, and developer productivity through streamlined CI/CD and testing. Top 3-5 achievements highlight how business value and technical excellence were delivered this month across the repository mbta/dotcom.
March 2025
February 2025
28 Commits • 15 Features
Feb 1, 2025February 2025 highlights for mbta/dotcom: UX improvements across autocomplete and trip planning, reliability enhancements for OTP timeouts and weekend service handling, and expanded subway information visibility on the homepage and alerts pages. Significant infrastructure and QA work included updating Phoenix LiveView dependencies, adding a StrictModuleLayout readability check with Credo, and CSP header refinements. Several UI and component refactors (two new DotcomWeb components, refactors of alerts and route symbols) contributed to a tighter, more secure, and more scalable codebase. These changes deliver measurable business value by increasing user satisfaction, reducing failure modes, and enabling smoother deployments.
February 2025
28 Commits • 15 Features
Feb 1, 2025February 2025 highlights for mbta/dotcom: UX improvements across autocomplete and trip planning, reliability enhancements for OTP timeouts and weekend service handling, and expanded subway information visibility on the homepage and alerts pages. Significant infrastructure and QA work included updating Phoenix LiveView dependencies, adding a StrictModuleLayout readability check with Credo, and CSP header refinements. Several UI and component refactors (two new DotcomWeb components, refactors of alerts and route symbols) contributed to a tighter, more secure, and more scalable codebase. These changes deliver measurable business value by increasing user satisfaction, reducing failure modes, and enabling smoother deployments.
January 2025
22 Commits • 12 Features
Jan 1, 2025January 2025 (mbta/dotcom) performance summary: Delivered significant UX and reliability improvements across the dotcom frontend, with attention to security, accessibility, and modernized tooling. Key features include Live.TripPlanner enhancements (/from and /to shortcuts; origin/destination switch), autocomplete improvements (geolocation source rewrite; mobile detached experience), and accessibility refinements (TripPlanner.Results live region). Security and maintenance efforts added broader basic auth credential support, while ongoing stability work updated core tooling (Metro updates to 0.1.18/0.1.19), Tailwind dependencies, and CSP hardening. These changes reduce user friction, improve search accuracy and accessibility, tighten security posture, and keep dependencies current for faster builds and better performance.
22 Commits • 12 Features
Jan 1, 2025January 2025 (mbta/dotcom) performance summary: Delivered significant UX and reliability improvements across the dotcom frontend, with attention to security, accessibility, and modernized tooling. Key features include Live.TripPlanner enhancements (/from and /to shortcuts; origin/destination switch), autocomplete improvements (geolocation source rewrite; mobile detached experience), and accessibility refinements (TripPlanner.Results live region). Security and maintenance efforts added broader basic auth credential support, while ongoing stability work updated core tooling (Metro updates to 0.1.18/0.1.19), Tailwind dependencies, and CSP hardening. These changes reduce user friction, improve search accuracy and accessibility, tighten security posture, and keep dependencies current for faster builds and better performance.
January 2025
December 2024
17 Commits • 2 Features
Dec 1, 2024December 2024 focused on delivering a more reliable, accessible, and business-friendly Trip Planner experience on mbta/dotcom. Key work delivered a comprehensive UX and data presentation refresh for the Trip Planner, including clearer itineraries, enhanced leg/place displays, robust error handling, and visual consistency; implemented display of backend error messages and improved route color handling. Autocomplete libraries were upgraded to improve accessibility and type safety. Email delivery reliability was stabilized by switching the Base64 encoder and pinning a stable mail library. Route data was standardized with redirects for closed routes in line with Bus Network Redesign. Test reliability was boosted through smoke/test updates and staging-flaky-test mitigations. These changes reduce user confusion, improve reliability, and lower support costs while enabling faster, safer releases.
December 2024
17 Commits • 2 Features
Dec 1, 2024December 2024 focused on delivering a more reliable, accessible, and business-friendly Trip Planner experience on mbta/dotcom. Key work delivered a comprehensive UX and data presentation refresh for the Trip Planner, including clearer itineraries, enhanced leg/place displays, robust error handling, and visual consistency; implemented display of backend error messages and improved route color handling. Autocomplete libraries were upgraded to improve accessibility and type safety. Email delivery reliability was stabilized by switching the Base64 encoder and pinning a stable mail library. Route data was standardized with redirects for closed routes in line with Bus Network Redesign. Test reliability was boosted through smoke/test updates and staging-flaky-test mitigations. These changes reduce user confusion, improve reliability, and lower support costs while enabling faster, safer releases.
November 2024
17 Commits • 5 Features
Nov 1, 2024Month: 2024-11. Focused delivery on security hardening, UI navigation modernization, dependency management, CI reliability, and user-relevant feature updates. Achieved measurable business value through improved security posture, more maintainable navigation/assets, stable builds, and more relevant user experiences for predictions.
17 Commits • 5 Features
Nov 1, 2024Month: 2024-11. Focused delivery on security hardening, UI navigation modernization, dependency management, CI reliability, and user-relevant feature updates. Achieved measurable business value through improved security posture, more maintainable navigation/assets, stable builds, and more relevant user experiences for predictions.
November 2024
Activity
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Quality Metrics
Correctness87.4%
Maintainability86.4%
Architecture82.0%
Performance81.2%
AI Usage22.6%
Skills & Technologies
Programming Languages
BashCSSCSVDockerfileEexElixirErlangGettextHEEXHEEx
Technical Skills
API DevelopmentAPI IntegrationAPI RefactoringAPI developmentAPI integrationAWSAccessibilityAlgoliaAlgolia AutocompleteAlgolia SearchArtilleryAuthenticationBackend DevelopmentBuild SystemsBuild Tools
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