A method and apparatus for composing software are described. In one embodiment, the apparatus comprises a loader to obtain software structure data identifying a plurality of application components associated with requested functionality and to obtain software logic data indicating interaction rules between the plurality of application components, a parameter index generator to parse a description file and generate an index for each parameter of the plurality of application components, a parameter mapping to map input, output and state parameters to indices that are used by application components to access the input, output and state parameters, and a scheduler to coordinate an invocation of the plurality of application components at run time based on the software logic data.