Methods and systems are described for automatically rendering a customized user interface (UI). A server receives a request to generate a UI, the request including a user identifier and a workflow identifier. The server determines a template based upon the workflow identifier, comprising areas for insertion of custom UI elements. The server captures a list of UI nodes, each UI node comprising metadata. The server organizes the UI nodes into (i) a tree data structure comprising an anchor UI node and child UI nodes, and (ii) a table data structure of identifiers for the nodes in the tree structure, values, constraints, and the metadata for the corresponding UI node. The server inserts the metadata into the areas for insertion using the tree data structure and the table data structure. The server renders a graphical UI based upon the metadata.