The present invention enables a user to build user-interfaces and applications based on a policy that contains metadata. The user can build an application through the user-interface, in which the user-interface and the generated computer-executable instructions are consistent with the policy. A user-interface has a toolbox that indicates the discovered components and a design surface that displays applicable stages. The policy determines the stages, where each stage provides a grouping of components having related tasks. The user selects components from the toolbox so that the selected components are associated with the selected stages on the design surface. After the user has completed building an application, a representation of the application may be compiled in order to generate a set of computer-executable instructions. Moreover, the compiler is coupled to the policy so that the set of computer-executable instructions is consistent with the policy.