Abstract: A message tracking engine facilitates processing of a message through a determined workflow. In particular, the message tracking engine may route the message to various services in an order specified by the workflow. During processing, the message tracking engine tracks the progress of the message through the workflow. If any issues are encountered, the message tracking engine handles the encountered issues. In one aspect, the message tracking engine facilitates performance of one or more synchronous processing steps of the workflow during a first phase. Following the first phase, the message tracking engine serializes one or more asynchronous processing steps of the workflow to a storage device. After serializing the asynchronous processing steps, the message tracking engine facilitates performance of the asynchronous processing steps during a second phase.