Parallel Development

Parallel development is a term used to describe the concurrent development activities necessitated by the complexity of today's applications and the pace at which these applications are developed. Aspects of parallel development include:

Several programmers working on the same application and often the same programs.
Identifying and resolving conflicts in programs that have been independently updated by more than one programmer.
The time-consuming, resource-intensive, and error-prone process of manually integrating independent changes to a program.
Reconciling differences between customized vendor software packages and vendor release updates.
Assessing project complexity, duration, and the resource requirements.

There are three general kinds of parallel development:

Simple parallel development: Concurrent work by a small number of programmers on modifications to a single program.
Complex parallel development: Concurrent work on multiple or overlapping releases by several teams of programmers.
Vendor application updates: Integrating customization to a base release of vendor or internally developed software with a subsequent release of the software.

Each of these is discussed in the following sections. The discussion includes a problem typical of that kind of parallel development.