I just finished a two month sprint on advancing CalendarFX and getting it ready for release 8.4.0. One focus of this sprint was on performance. There are many things that can influence performance but when it comes to JavaFX the number of nodes in your scenegraph and CSS styling are top candidates for optimisation. After reviewing the custom controls that ship with CalendarFX I realized that many of them used a lot of nested panes (BorderPane, VBox, HBox, GridPane) in order to achieve a specific layout. Nested panes result in a high node count and complex CSS styling instructions.
One simple example are the views that CalendarFX creates to visualize calendar entries in the DayView control. This control shows the 24 hours of a day vertically and places DayEntryView instances on them. These entry views look like this: