Abstract: This disclosure generally relates to executing dynamically generated applications in a web browser-based shell. An exemplary method generally includes instantiating shared components in the browser-based shell, the shared components exposing a common runtime environment to widgets loaded into the browser-based shell. A first workflow definition representing a first step of a workflow is received. The first workflow definition specifies first widgets, comprising modular components that perform functions represented by the first step of the workflow and comprising a user interface definition, to be loaded into the browser-based shell. The first widgets are obtained from one or more of a remote source, a local cache, or a temporary memory and loaded into the browser-based shell. A user interface is generated according to the first workflow definition to exposes the function to a user which, when invoked, initiates a transition to a second step of the workflow.