Ant Design System for Figma - A large library of 2100+ handcrafted UI components
UMLGraph - UMLGraph is a professional automated drawing tool that allows the designers the declarative specification and drawing of UML class and sequence diagram.
DaisyUI - Free UI components plugin for Tailwind CSS
draw.io - Online diagramming application
UI Playbook - The documented collection of UI components
yEd - yEd is a free desktop application to quickly create, import, edit, and automatically arrange diagrams. It runs on Windows, Mac OS X, and Unix/Linux.