We’re enabling developers to easily add custom visuals into Power BI for use in dashboard, reports and content packs. To help you get started, we’ve published the code for all of our visualizations to GitHub. Along with the visualization framework, we’ve provided our test suite and tooling to help the community build high quality custom visuals for Power BI. All of this is available as an open source project on GitHub.
For additional Power BI Custom Visuals documentation, see Custom visuals in Power BI on docs.microsoft.com.