Development Process

For business systems, the process should be based on UML, Rational Unified Process and Extreme Programming.

These subjects are large with many books/articles available. This is a brief summary with key points highlighted with insights tempered with experience.

The objective is to develop a system that:

• Satisfies both functional and non-functional requirements
• Can change and evolve

Change is inevitable - critical to resilience is the nature of the system partitioning. By using components, each with a clearly defined interface, component substitution is possible. In addition, this may allow re-use typically at the domain object level - realistically, total re-use of an entire system implementation is not possible.

To counteract the main root causes of over-budget, late, poor quality software, these best practices should be followed:

• Develop iteratively
• Manage requirements
• Use component architectures
• Model visually
• Continuously verify quality
• Manage change

As the system evolves, each release must:

• Be treated as a small project
• Result in an executable
• Be exercised by end-users and feedback incorporated in the next release(s)