QW2001 Paper 7M1

Mr. Michael Ensminger
(PAR3 Communications)

Walk & Stagger Through Review Process

Key Points

Presentation Abstract

The use of peer reviews, walkthroughs and inspections as a cost-effective method for achieving higher quality software is well documented. These techniques are not regularly used in many organizations, especially those that say they are operating on “Internet time”. At two Internet startups, I have used a modified, 2-phase walkthrough process to successfully deliver high quality software. The process proved successful, especially with teams without review experience. Contrary to what others in the organization were proposing, the teams using the process were able to deliver more quickly even with the increased “up front” work than other teams in the same organization.

The modified walkthrough process begins with the “Walk Through” (two words to distinguish it from the traditional use of the word walkthrough). During the walk through, the item being reviewed is examined in the order of machine execution or user experience in the “normal” course of operation. This first phase ensures that the item meets its stated goals. Once the “normal” course of action is completed, it is time to throw obstacles in the course of execution so that the team must stagger through what they just verified was correct. The stagger through phase examines error cases and “what if” scenarios. The division of labor - first focusing and algorithmic correctness and then looking at error handling and other situations - allows the team to stay focused, review each item with more or less the same thoroughness and does not waste team time fully inspecting an item which does not meet the basic goals. The paper details the team composition, process and scheduling details that a team lead must consider when implementing this approach.

A case study is presented for a project from Partes Corporation involving an Internet based data store and desktop machine analysis. The team, on the whole, was inexperienced in producing production quality code. The walk / stagger through process extended the design phase to probably twice the length that other teams would declare design complete. However, the coding and testing phases progressed much faster than expected more than offsetting the time spent in design.

About the Author

Michael Ensminger is Director of Quality Assurance at PAR3 Communications based in Seattle, WA. Prior experience (both management and practitioner of test and development teams) includes Internet, shrink-wrap and niche retail banking software. He holds a M.S. in Computer Science from University of Texas at Dallas.