Some Rapid Application Development (RAD) Principles Dr. Ernest Cachia

Some Rapid Application Development (RAD) Principles Dr. Ernest Cachia

Main RAD Players User involvement Strict (and usually fast) delivery times Prototyping Effective use of modern development tools Reduction of the requirements capture and analysis effort Incremental development

User Involvement JAD Decision taking Sign-offs Prototype demos Bite size development focus Problem detection and correction

Strict Delivery Times Timebox approach 2 to 6 weeks Prioritisation (MoSCoW rules) Must, Should, Could, Want to, have User agreement Power of decision

DSDM- An SDLC based on RAD Is a standard used throughout the UK and a number of other countries. Yet others, use it sparingly Is an “open” method – i.e. noncommercialised Is supported by a consortium also called the “DSDM Consortium” see site: dsdm.org

DSDM Does not specify a particular method of development to use in its phases Just offers a framework upon which development may proceed and at which points and what sort of milestone to produce Really only covers analysis, design and implementation phases

RAD Principles (9 in all) (1/2) 1. Win-Win (my addition) 2. All stakeholders must take active part 3. All stakeholders can take binding decisions 4. Deliverables are frequent 5. Deliverables must clearly map on to the business process 6. Deliverables are bite-sized

RAD Principles (9 in all) (2/2) 7. All development effort is reversible 8. Requirements are agreed upon at a high level – i.e. the method of their actual implementation is not that important 9. Testing permeates the SDLC 10. Collaboration, not competition between stakeholders is of essence

The DSDM Filter When to use DSDM? Answer these Is the functionality visible through the UIs? Can all end user classes be identified? Is the system heavy on computation? Is the system “large” and can it be sensibly split up? How time-constrained is the project? Are requirements abstract enough and can they change within limits?

Systems that can benefit from DSDM Interactive Based on UIs (functionally) User groups are clearly defined Not too complex Can be incrementally developed Time-wise guaranteed Requirements can be prioritised Requirements can undergo changes

The End Good luck to you all!