highcharts/highcharts
Oct 2024 – Feb 2026
17 Months active
Languages Used
JavaScriptMarkdownTypeScriptCSSHTMLMJS
Technical Skills
Chart LibrariesDocumentationFront End DevelopmentJavaScriptUnit TestingTechnical Writing
Kacper Madej
PROFILE
Kacper Madej
Kacper Madej contributed extensively to the highcharts/highcharts repository, focusing on chart rendering, API stability, and documentation quality. Over 17 months, Kacper delivered robust features and bug fixes that improved chart interactivity, data visualization accuracy, and cross-platform reliability. He refactored core modules, enhanced TypeScript type safety, and streamlined documentation through doclet migration and tag hygiene. By addressing floating-point precision, accessibility, and test suite stability, Kacper ensured maintainable code and a smoother developer experience. His work leveraged JavaScript, TypeScript, and CSS, demonstrating depth in front-end development, code refactoring, and technical writing while reducing long-term maintenance costs for the project.
Overall Statistics
Feature vs Bugs
52%Features
Repository Contributions
200Total
Bugs
43
Commits
200
Features
46
Lines of code
23,536
Activity Months17
Your Network
56 peopleSame Organization
@blacklabel.net3
Shared Repositories
53
Work History
February 2026
2 Commits • 1 Features
Feb 1, 2026February 2026 — Axis options typing refinements and rendering robustness for highcharts/highcharts. Consolidated axis option typing, making axis titles and parallel coordinates options more flexible by simplifying type definitions, and then stabilized rendering by ensuring axis titles and styles are always defined. This work improves developer experience and reduces runtime rendering issues across chart types. Commit references: fbd12d073f1b69aa5ba348eff90f96680a785203; 230dc33bcb5f76bcf914f5f03dcc4a0ad775339e.
2 Commits • 1 Features
Feb 1, 2026February 2026 — Axis options typing refinements and rendering robustness for highcharts/highcharts. Consolidated axis option typing, making axis titles and parallel coordinates options more flexible by simplifying type definitions, and then stabilized rendering by ensuring axis titles and styles are always defined. This work improves developer experience and reduces runtime rendering issues across chart types. Commit references: fbd12d073f1b69aa5ba348eff90f96680a785203; 230dc33bcb5f76bcf914f5f03dcc4a0ad775339e.
February 2026
January 2026
24 Commits • 8 Features
Jan 1, 2026In January 2026, the highcharts/highcharts repo delivered targeted refactoring and quality improvements that reduce maintenance burden and improve reliability of the Series API. Key features delivered include Series class doclet consolidation, moving public doclets from SeriesBase to Series (including migration in Series.ts and SeriesDefaults.ts) and doclet cleanup; TS public types fixed; import corrections after merge; DL options type updated to exclude point-level zIndex; UI/UX thumbnails polish; a11y doclet updates and accessibility improvements; lint cleanup.
January 2026
24 Commits • 8 Features
Jan 1, 2026In January 2026, the highcharts/highcharts repo delivered targeted refactoring and quality improvements that reduce maintenance burden and improve reliability of the Series API. Key features delivered include Series class doclet consolidation, moving public doclets from SeriesBase to Series (including migration in Series.ts and SeriesDefaults.ts) and doclet cleanup; TS public types fixed; import corrections after merge; DL options type updated to exclude point-level zIndex; UI/UX thumbnails polish; a11y doclet updates and accessibility improvements; lint cleanup.
December 2025
42 Commits • 6 Features
Dec 1, 2025December 2025 monthly summary for highcharts/highcharts: Delivered foundational refactors, API stabilization, and documentation improvements that reduce long-term maintenance cost and improve developer experience. Core/Series structural refactor, targeted doclet relocation and tag hygiene, and comprehensive type-safety enhancements laid groundwork for faster feature delivery and fewer regressions. Ongoing test fixes and internal tagging adjustments improved reliability and public API exposure, complemented by documentation/documentation tooling improvements and doclet migrations to align code and docs with current usage.
42 Commits • 6 Features
Dec 1, 2025December 2025 monthly summary for highcharts/highcharts: Delivered foundational refactors, API stabilization, and documentation improvements that reduce long-term maintenance cost and improve developer experience. Core/Series structural refactor, targeted doclet relocation and tag hygiene, and comprehensive type-safety enhancements laid groundwork for faster feature delivery and fewer regressions. Ongoing test fixes and internal tagging adjustments improved reliability and public API exposure, complemented by documentation/documentation tooling improvements and doclet migrations to align code and docs with current usage.
December 2025
November 2025
41 Commits • 15 Features
Nov 1, 2025November 2025 contributions to highcharts/highcharts focused on documentation quality, TypeScript safety, and API hygiene, delivering groundwork for maintainability and faster onboarding while preserving feature parity.
November 2025
41 Commits • 15 Features
Nov 1, 2025November 2025 contributions to highcharts/highcharts focused on documentation quality, TypeScript safety, and API hygiene, delivering groundwork for maintainability and faster onboarding while preserving feature parity.
October 2025
4 Commits • 1 Features
Oct 1, 2025Month 2025-10 summary for highcharts/highcharts: Delivered targeted demo enhancements and stability fixes that strengthen product visibility, reduce onboarding friction, and improve test reliability. Key features delivered: Demo Data and Documentation Updates enhancing Norway map example, extended demo availability, and promoted Highcharts Grid in demos and readme. Major bugs fixed: Stability fixes in the Gantt demo (drag handles after refactor) and correction of map data references in unit tests, improving test reliability and CI stability. Overall impact: strengthened developer experience and demo quality, reduced risk in releases, and improved maintainability of demo content and test suite. Technologies/skills demonstrated: JavaScript/Highcharts internals, data updates and metadata management, test debugging, documentation, and version-control discipline.
4 Commits • 1 Features
Oct 1, 2025Month 2025-10 summary for highcharts/highcharts: Delivered targeted demo enhancements and stability fixes that strengthen product visibility, reduce onboarding friction, and improve test reliability. Key features delivered: Demo Data and Documentation Updates enhancing Norway map example, extended demo availability, and promoted Highcharts Grid in demos and readme. Major bugs fixed: Stability fixes in the Gantt demo (drag handles after refactor) and correction of map data references in unit tests, improving test reliability and CI stability. Overall impact: strengthened developer experience and demo quality, reduced risk in releases, and improved maintainability of demo content and test suite. Technologies/skills demonstrated: JavaScript/Highcharts internals, data updates and metadata management, test debugging, documentation, and version-control discipline.
October 2025
September 2025
8 Commits • 3 Features
Sep 1, 2025September 2025 monthly summary for highcharts/highcharts focused on delivering stability, reliability, and maintainability in chart rendering. Key features include robust tooltip interaction on hover with stickOnContact, refactoring data label grouping and cleansing z-index usage to stabilize rendering, and linting behavior validation with reversible changes. Major bug fix removed an unused tooltipTimeout from Pointer class to reduce dead code. These efforts improved user-facing reliability, developer productivity, and overall chart performance.
September 2025
8 Commits • 3 Features
Sep 1, 2025September 2025 monthly summary for highcharts/highcharts focused on delivering stability, reliability, and maintainability in chart rendering. Key features include robust tooltip interaction on hover with stickOnContact, refactoring data label grouping and cleansing z-index usage to stabilize rendering, and linting behavior validation with reversible changes. Major bug fix removed an unused tooltipTimeout from Pointer class to reduce dead code. These efforts improved user-facing reliability, developer productivity, and overall chart performance.
August 2025
3 Commits
Aug 1, 2025August 2025 monthly summary for highcharts/highcharts focusing on geometry precision and tooltip visuals. Delivered key fixes, improved test coverage, and reinforced maintainability to deliver reliable charts and consistent UI across browsers. Emphasis on business value through accurate geometry calculations and stable user experience across chart types.
3 Commits
Aug 1, 2025August 2025 monthly summary for highcharts/highcharts focusing on geometry precision and tooltip visuals. Delivered key fixes, improved test coverage, and reinforced maintainability to deliver reliable charts and consistent UI across browsers. Emphasis on business value through accurate geometry calculations and stable user experience across chart types.
August 2025
July 2025
3 Commits
Jul 1, 2025January 2025-07 monthly summary focusing on stability, UX, and user value for Highcharts rendering. This period prioritized robustness in rendering paths, color handling, and chart interactivity across layout changes, with targeted fixes that reduce crashes and improve user experience during zoom and responsive UI interactions.
July 2025
3 Commits
Jul 1, 2025January 2025-07 monthly summary focusing on stability, UX, and user value for Highcharts rendering. This period prioritized robustness in rendering paths, color handling, and chart interactivity across layout changes, with targeted fixes that reduce crashes and improve user experience during zoom and responsive UI interactions.
June 2025
20 Commits • 3 Features
Jun 1, 2025June 2025 performance summary for highcharts/highcharts: Focused on UX and robustness of chart interactions, especially Gantt/TreeGrid axis and breaks UI, with pixel-accurate scrollbars and reliable tooltip behavior. Refined StaticScale handling for smoother scrolling after axis option changes and implemented thorough code cleanup, type-safety improvements, and documentation/licensing hygiene. Result: more stable user experience, easier maintenance, and clearer API/docs for developers and customers.
20 Commits • 3 Features
Jun 1, 2025June 2025 performance summary for highcharts/highcharts: Focused on UX and robustness of chart interactions, especially Gantt/TreeGrid axis and breaks UI, with pixel-accurate scrollbars and reliable tooltip behavior. Refined StaticScale handling for smoother scrolling after axis option changes and implemented thorough code cleanup, type-safety improvements, and documentation/licensing hygiene. Result: more stable user experience, easier maintenance, and clearer API/docs for developers and customers.
June 2025
May 2025
7 Commits • 2 Features
May 1, 2025May 2025 highlights for highcharts/highcharts. Key features delivered: Offline Exporting and AST Enhancements (extends AST for offline/pdf export; moved offline-export AST changes into OfflineExporting extension) and CI/Unit Test Stability Improvements (reducing flakiness via adjusted assertions and approximate equality). Major bugs fixed: Axes and Scrollbar Robustness Improvements (edge-case break calculations and scrollbar range handling) and Map Data Samples Update (France 2024, Italy 2024, Kazakhstan 2022, South Dakota, Virginia). Overall impact: improved offline/export fidelity, more reliable cross-browser tests, and up-to-date geographic data for maps. Technologies/skills demonstrated: AST refactoring, extension architecture, test stabilization, cross-browser rendering, data maintenance.
May 2025
7 Commits • 2 Features
May 1, 2025May 2025 highlights for highcharts/highcharts. Key features delivered: Offline Exporting and AST Enhancements (extends AST for offline/pdf export; moved offline-export AST changes into OfflineExporting extension) and CI/Unit Test Stability Improvements (reducing flakiness via adjusted assertions and approximate equality). Major bugs fixed: Axes and Scrollbar Robustness Improvements (edge-case break calculations and scrollbar range handling) and Map Data Samples Update (France 2024, Italy 2024, Kazakhstan 2022, South Dakota, Virginia). Overall impact: improved offline/export fidelity, more reliable cross-browser tests, and up-to-date geographic data for maps. Technologies/skills demonstrated: AST refactoring, extension architecture, test stabilization, cross-browser rendering, data maintenance.
April 2025
8 Commits • 1 Features
Apr 1, 2025April 2025 highlights for highcharts/highcharts: Delivered documentation improvements for module initialization, simplifying imports for modules like accessibility and exporting, and removing unnecessary initialization calls to boost clarity and consistency in examples. Strengthened the test suite with reliability and cross-browser compatibility improvements across Windows+Firefox, Linux CI, and subpixel DOM calculations, addressing flaky results and stabilizing CI workflows. Overall impact: clearer developer onboarding, faster and more reliable releases, and a more robust end-user experience. Technologies demonstrated: documentation practices, cross-browser testing, CI/CD configurations, and thorough test maintenance across multiple environments.
8 Commits • 1 Features
Apr 1, 2025April 2025 highlights for highcharts/highcharts: Delivered documentation improvements for module initialization, simplifying imports for modules like accessibility and exporting, and removing unnecessary initialization calls to boost clarity and consistency in examples. Strengthened the test suite with reliability and cross-browser compatibility improvements across Windows+Firefox, Linux CI, and subpixel DOM calculations, addressing flaky results and stabilizing CI workflows. Overall impact: clearer developer onboarding, faster and more reliable releases, and a more robust end-user experience. Technologies demonstrated: documentation practices, cross-browser testing, CI/CD configurations, and thorough test maintenance across multiple environments.
April 2025
March 2025
1 Commits
Mar 1, 2025March 2025 monthly summary for highcharts/highcharts focused on stability and reliability improvements. Delivered a critical bug fix to the destroy lifecycle that prevents runtime errors when wrapper[key] is missing, and ensured the fix passes the test suite. No new features were released this month; the emphasis was on bug resolution and test hygiene to reduce support risk and improve customers' runtime stability.
March 2025
1 Commits
Mar 1, 2025March 2025 monthly summary for highcharts/highcharts focused on stability and reliability improvements. Delivered a critical bug fix to the destroy lifecycle that prevents runtime errors when wrapper[key] is missing, and ensured the fix passes the test suite. No new features were released this month; the emphasis was on bug resolution and test hygiene to reduce support risk and improve customers' runtime stability.
February 2025
12 Commits • 2 Features
Feb 1, 2025February 2025 monthly summary for highcharts/highcharts focused on stabilizing visuals, improving developer experience, and enhancing documentation. Delivered user-visible fixes for label rendering, improved zoom-cropping behavior in the Boost module, and tightened navigation UI stability, alongside code quality refactors and documentation updates that collectively raise reliability and maintainability while preserving business value for charting applications.
12 Commits • 2 Features
Feb 1, 2025February 2025 monthly summary for highcharts/highcharts focused on stabilizing visuals, improving developer experience, and enhancing documentation. Delivered user-visible fixes for label rendering, improved zoom-cropping behavior in the Boost module, and tightened navigation UI stability, alongside code quality refactors and documentation updates that collectively raise reliability and maintainability while preserving business value for charting applications.
February 2025
January 2025
17 Commits • 1 Features
Jan 1, 2025January 2025 focused on stability, performance, and cross-environment compatibility. Delivered targeted fixes across core rendering, interaction, and demo features that reduce user-facing issues and strengthen data storytelling in charts and maps. The work enhances reliability for enterprise deployments, improves demo reproducibility, and broadens browser/environment support.
January 2025
17 Commits • 1 Features
Jan 1, 2025January 2025 focused on stability, performance, and cross-environment compatibility. Delivered targeted fixes across core rendering, interaction, and demo features that reduce user-facing issues and strengthen data storytelling in charts and maps. The work enhances reliability for enterprise deployments, improves demo reproducibility, and broadens browser/environment support.
December 2024
5 Commits • 1 Features
Dec 1, 2024December 2024 monthly summary for highcharts/highcharts: Focused on cross-platform stability and developer experience. Delivered Windows environment and testing fixes to improve CI reliability and reduce Windows-specific failures, and implemented documentation enhancements to help contributors with nightly builds and API reference usage. Overall impact includes improved cross-OS compatibility, faster onboarding for Windows contributors, and clearer guidance for ongoing development.
5 Commits • 1 Features
Dec 1, 2024December 2024 monthly summary for highcharts/highcharts: Focused on cross-platform stability and developer experience. Delivered Windows environment and testing fixes to improve CI reliability and reduce Windows-specific failures, and implemented documentation enhancements to help contributors with nightly builds and API reference usage. Overall impact includes improved cross-OS compatibility, faster onboarding for Windows contributors, and clearer guidance for ongoing development.
December 2024
November 2024
1 Commits • 1 Features
Nov 1, 2024Concise monthly summary for 2024-11 focusing on key features delivered, major bugs fixed, impact, and technologies demonstrated. This month’s primary deliverable was a Contribution Guidelines Documentation Update for highcharts/highcharts, restructuring and clarifying guidelines, adding changelog-writing guidance, and centralizing references to improve onboarding and policy adherence. No major bug fixes were recorded in this cycle. Overall, this work improves contributor onboarding efficiency, accelerates policy adoption, and strengthens documentation governance. Technologies demonstrated include Markdown/documentation engineering, repository maintenance practices, and cross-document references.
November 2024
1 Commits • 1 Features
Nov 1, 2024Concise monthly summary for 2024-11 focusing on key features delivered, major bugs fixed, impact, and technologies demonstrated. This month’s primary deliverable was a Contribution Guidelines Documentation Update for highcharts/highcharts, restructuring and clarifying guidelines, adding changelog-writing guidance, and centralizing references to improve onboarding and policy adherence. No major bug fixes were recorded in this cycle. Overall, this work improves contributor onboarding efficiency, accelerates policy adoption, and strengthens documentation governance. Technologies demonstrated include Markdown/documentation engineering, repository maintenance practices, and cross-document references.
October 2024
2 Commits • 1 Features
Oct 1, 2024October 2024: Delivered feature improvements and stability for Highcharts. Implemented Scrollable Plot Area Extension Refactor with utility-based CSS class management and expanded unit tests to validate chart updates and behavior with parallel coordinates enabled and disabled. Fixed FAQ documentation by correcting the iframe URL trailing slash to ensure embedded content loads reliably. These efforts improved chart update robustness and reliability of embedded content, reducing user-facing issues.
2 Commits • 1 Features
Oct 1, 2024October 2024: Delivered feature improvements and stability for Highcharts. Implemented Scrollable Plot Area Extension Refactor with utility-based CSS class management and expanded unit tests to validate chart updates and behavior with parallel coordinates enabled and disabled. Fixed FAQ documentation by correcting the iframe URL trailing slash to ensure embedded content loads reliably. These efforts improved chart update robustness and reliability of embedded content, reducing user-facing issues.
October 2024
Activity
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Quality Metrics
Correctness92.0%
Maintainability91.6%
Architecture88.2%
Performance88.6%
AI Usage22.0%
Skills & Technologies
Programming Languages
CSSHTMLJavaScriptMJSMarkdownTypeScript
Technical Skills
API DesignAPI DevelopmentAPI DocumentationAccessibilityAnnotation ManagementBuild ToolsCI/CDCSSChart DevelopmentChart LibrariesChart RenderingCharting LibrariesCode DocumentationCode MaintainabilityCode Maintenance
Repositories Contributed To
Overview of all repositories you've contributed to across your timeline