IT Club 25 th October 2007, London

Transcription

1 IT Club 25 th October 2007, London Agile v Waterfall: Brief Overview of Strengths and Weaknesses Presented by: Dragan Jojic Managing Consultant Conchango plc

2 Introducing Conchango Overview Privately held British Consultancy and Systems Integrator Founded in 1991 Blue chip client base Business acumen supported by technical heritage Size and Scale Offices in the UK (London, Egham), USA and India 280 business and technology consultants Access to 100 off-shore developers Integrated Teams Sector expertise Retail and Consumer Products Financial Services including Insurance Energy Media and Entertainment

3 What We Do and Who We Do It For Conchango services IT Strategy and Business Consulting Project Delivery and Coaching User Experience (Creative Design, Usability, Accessibility) Application Development and Systems Integration Business Intelligence Enterprise Architecture Support and Maintenance Conchango experience in the Lloyd s Market Hiscox: Built triangulations analysis & underwriter performance system Lloyd s of London Initiated and participated in the Data Management programme Lead lloyds.com redesign, redevelopment & content migration Involved in building systems for Coverholders Management and Syndicates Performance Review based on MOSS 2007

4 Definition of Terms Waterfall Methodologies Predictive, phased methods for managing software development Date from 1970s; based on optimising resources around roles and breaking the work into modules Usually made up of a structured set of components, techniques & processes Focus on process & documentation e.g. PRINCE 2 Agile An umbrella term for empirical approaches to software development Born out of Lean Manufacturing Techniques in early 1990s Articulated by Agile Manifesto in 2001 Incremental and iterative by nature Focus on people, interactions and delivering working software e.g. Scrum

5 The Great Agile Myth Agile According to Dilbert

6 Source: Forrester Research Inc Causes of Project Failure According to Forrester Research, up to 60% of software development projects fail Any project management and software development methodology applied competently should be able to address these causes

7 Poorly Scoped Projects Waterfall Approach Detailed requirements analysis and scope definition up-front Business sign-off before moving on, with Project Manager managing the scope thereafter Scope seen to be largely fixed Strengths Results in defined scope, timescale and budget Provides management with the sense of clarity and security Weaknesses Higher cost of detailed requirements analysis up-front Can produce bloated solutions with a number of unnecessary requirements Expectations are set early on Agile Approach High-level requirements analysis up-front, then ongoing scope and requirements definition and clarification Business owns and manages changes to the scope based on the business value Scope seen as flexible Strengths Lower investment up-front and earlier start Improves ability to respond to change Produces a solution that fits real business need Weaknesses It takes time to build trust Either the scope or the timescale/budget has to remain variable Relies on the Business to provide their time and input throughout the project

8 Buggy Software Waterfall Approach Clearly defined development and testing roles with Testers responsible for quality Requirements definition and system design done up-front Communication through documents Testing following the development Agile Approach The whole team responsible for quality Business available to provide input and review functionality as it is developed Communication face-to-face Testing in parallel with development, ideally leading test driven development Strengths Following well established practices no need for learning and adjusting Weaknesses Difficult to estimate time required for testing phase at the end of the project Longer leg between developing a feature and having to fix a bug the testing found No explicit focus on code quality Strengths Explicit focus on code quality with early discovery of defects leading to lower cost Increases communication and visibility Weaknesses Requires the team to adopt a new set of engineering practices Expects individuals to be self motivated, take ownership and think for themselves

9 Technical or integration issues Waterfall Approach All design decisions made up-front System Architect responsible for design Team responsible for addressing issues Infrequent deployments, very complicated and rarely go smoothly Agile Approach Design decisions made when required The whole team responsible for design Business involved in addressing issues Regular deployment and continuous integration Strengths Design clarity (perception of) at the outset Makes developers lives easier Weaknesses Technical and integration issues discovered too late - more costly System Architect - single point of failure Strengths Technical and integration issues discovered and addressed early and regularly Evolving solution architecture Weaknesses Relies on having a number of environments available (Dev, Sys Test, UAT, Prod ) Evolving solution architecture

10 Agile In Summary Strengths Improves ability to respond to change Produces a solution that fits real business need Provides explicit focus on code quality Increases communication and visibility Weaknesses It takes time to build trust Relies on the Business to provide their time and input throughout the project Requires the team to adopt a new set of engineering practices Expects individuals to be self motivated, take ownership and think for themselves Considerations Agile is not a silver bullet Agile is easy to understand but not as easy to put in place and keep following

11 Agile Resources Books Lean Software Development by Mary Poppendieck and Tom Poppendieck Agile Software Development with Scrum by Ken Schwaber and Mike Beedle Agile Estimating and Planning by Mike Cohn Agile Retrospectives by Esther Derby and Diana Larsen Web resources (by Conchango) Events Fall 2007 Scrum Gathering London, November 2007 for details see:

12 Thank you! For more information:

13 The Agile Manifesto While there is value in the items on the right, we value the items on the left more. Individuals & interactions Working Software Customer Collaboration Responding to Change over over over over Processes & Tools Comprehensive Documentation Contract Negotiation Following a Plan

14 Scrum on a Slide

15 Wasted Effort Features and Functions Used in a Typical System Often or Always Used: 20% Sometimes 16% Rarely 19% Often 13% Never 45% Always 7% Rarely or Never Used: 64% Standish Group Study Reported at XP2002 by Jim Johnson, Chairman

16 Faster Return On Investment Waterfall Agile Release 1 Release 2 Release 3 Release 4 Release 5 Time ROI Go Live