Bellissima was born
Umbraco 14 introduced the new Umbraco Backoffice. Built using modern technology and an "extension first" architecture, Project Bellissima was a long overdue overhaul of an antiquated codebase using AngularJS.
Frustrating but rewarding
The complexity in upgrading Umbraco solutions from 13 to 14 largely depended on custom extensions such as property editors, dashboards, trees, content apps and sections.
No longer could I look at the detailed documentation, existing well-established code or forum posts with that JustRight™ AngularJS hack to get my custom extensions working.
I felt alone, scared and confused.
However, the new codebase, Umbraco.UI, was near completion and documentation was (slowly) following. Popular packages such as uSync had pre-release builds that I could peek at and the community was busy writing blog posts on the new backoffice.
Upgrading my Umbraco Packages
Packages such as Relations Manager, Simple Dashboards and Simple Workspace Views heavily extend backoffice functionality.
Each existing feature had to be meticulously rebuilt using Lit and Umbraco UI. Many (late-night) hours were spent, but finally all packages were working in Umbraco 14.