Overlapping Release Lines

Synopsis::Cascade release development codelines.

Intent
To allow progress on incremental releases without them having a severe impact on one another.

Motivation
The increasing move to rapid and short release cycles is leading increasingly to a need for overlapping release development. Each release is started before the completion of the preceding release, moreover with overlapping releases it is common to have two or more concurrent releases in development simultaneously.

Applicability
Any development with an aggressive release schedule that demands multiple releases be in development at any given time.

Also known as
also known as::Parallel Feature Lines, also known as::Incremental and Evolutionary Delivery Lines

Structure
Releases are branched from the preceding release or, in the case of the first release, the main development line.



Consequences

 * Releases are isolated from one another to a degree.
 * Dependencies are created between later release lines and earlier ones.
 * There is a risk that, left unchecked, the cascading of releases run out of control and they are never consolidated.

Related patterns
There are no known variants to the Overlapping Release Lines pattern.

The following patterns are related to the pattern.
 * related pattern::Parallel Maintenance and Development Lines
 * related pattern::Merge Early and Often
 * related pattern::Propagate Early and Often
 * related pattern::Change Propagation Queues
 * related pattern::Policy Branch