An HTTP request handling runtime includes a context object and an event pipeline for processing an HTTP request received at a host application from a client application. The context object logically represents the HTTP request and encapsulates at least one property associated with the received HTTP request. The context object is processed by the event pipeline, which includes a plurality of synchronous and/or asynchronous request events. A callback is generated when a request event is raised and when at least one application and/or module is registered with the request event. Each callback instantiates each application and module that is registered with the request event for processing the context object. The plurality of request events can include events that are in a deterministic order and/or request events that are in a non-deterministic order, such as an error event.