About Dean Leffingwell

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1 Lean Practices for Foreword by Don Nonfunctional (System Qualities) Agile Style Reinertsen Development Series By and Ryan Shriver Agile 2010 Orlando, FL Lean Practices for Foreword by Don Reinertsen Development Series About Lean Practices for Foreword by Don Reinertsen Development Series Lean Practices for Foreword by Don Reinertsen Development Series 2

2 Development Series Development Series About Ryan Shriver Lean Practices for 3 Lean Practices for The first 90% of the code takes 90% of the development time. The remaining 10% of the code takes up the other 90% of the time. -- Tom Cargill, Bell Labs 4

3 Development Series Development Series Lean Practices for NONFUNCTIONAL REQUIREMENTS IN AGILE CONTEXT 5 The Agile Team in The Enterprise There can be a large number of teams in the enterprise pods of 5-10 teams building a feature, component, or subsystem is not unusual Lean Practices for Some product lines require teams to build However, the structure of each team is largely the same

4 Development Series Development Series Their work is based on the user story Lean Practices for User Story As a <role> I can <activity> So that <business value> As a Gmail user, I can select and highlight a conversation for further action Stories drive iterations Lean Practices for Story A Story B Story C Story D Story E Story F Story Plan Fixed Resources Fixed Time (Iteration) 8

5 Development Series Development Series Stories are maintained in the teams backlog Lean Practices for There is only one backlog for the team Backlog Item All work comes from the backlog Is one of If isn't a user story (defect, etc) it still goes in the backlog Story Implemented by 1 1..* Task If there isn t a story in the backlog, it ain t gonna happen A test and quality-centric approach Lean Practices for Teams perform unit testing and functional testing for every story Backlog Item Is one of The details of the story go into the functional test, where they are the persistent representation of system behavior Done when passes Story 1 Implemented by 1 1..* Task Stories are temporal (not maintained after implementation) 1..* Acceptance Test 1 Consists of Unit Test 1..* 1..* Functional Test

6 Development Series Development Series Scaling requires rethinking Lean Practices for Assume a program requires 200 practitioners, (25 agile teams) to deliver a product The enterprise delivers software every 90 days in five, two week iterations. Each team averages 15 stories per iteration. Number of stories that must be elaborated and delivered to achieve the release objective = 25*5*15= 1,875! How is an enterprise supposed to reason about things? What is this new product going to actually do for our users? If we have 900 stories complete, 50% done, what do we actually have working? How would we describe 900 things? How will we plan a release than contains 1,875 things? And, what if it took 500 people? 11 And further Lean Practices for And, even if I know 100 things that as a <role> I can <activity> so that <business value>, can do what Features does the system offer to its user and what benefits does it provide? Feature Stars for conversations Benefit Highlight conversations of special interests Colored label categorization Easy eye discrimination of different types of stories (folder like metaphor) Smart phone client application Faster and more facile use for phone users ease adoption 12

7 Development Series Development Series So we need an additional level of planning Features Product & Release Cycle Lean Practices for Release Planning Release Vision Release Scope and Boundaries Drives Stories Iteration Cycle Iteration Planning Feedback - Adjust Review & Adapt Develop & Test 13 Which creates an iteration and release pattern Lean Practices for Stories Release timebox 14

8 Development Series Development Series So we need to extend the information model Lean Practices for Features are another kind of Backlog Item Backlog Item Is one of Feature Realized by 0,1 1..* Story Implemented by 1 1..* Task Introduce Gmail Labels as a folder-like conversationorganizing metaphor. Or: As a modestly skilled user, I can assign more than one colored label to a conversation so that I can see a conversation from multiple perspectives Features also require testing Lean Practices for Backlog Item Is one of Feature Realized by 0,1 1..* Story 1 1 Done when passes Implemented by 1 1..* Task Features typically span many teams 1..* Acceptance Test Sometimes, a special team is dedicated for the purpose of testing system level features

9 Development Series Development Series What about nonfunctional requirements? Lean Practices for Features and user stories express functional requirements But other requirements determine system quality as well: Performance, reliability and security requirements Industry and Regulatory Standards Design constraints, such as those that provide common behavior across like components Typically, these system level qualities Span multiple components/products/applications/ services/subsystems Can often only be tested at the system level 17 NFRs can be considered as constraints on new development Lean Practices for Backlog Item Constrained by 0..* 0..* Non-functional Requirement Is one of Feature Realized by 0,1 1..* Story 1 1 Done when passes 1..* Acceptance Test Implemented by 1 1..* Task

10 Development Series Development Series Examples Lean Practices for Backlog Item Nonfunctional requirement As a consumer I want to be notified of any planned brownouts that could affect my home Constrained by All utility notifications shall be displayed within one minute of event As a mail user, I want to use folders to organize my mail for easier access Constrained by All web interfaces must be designed to meet accessibility requirements of WAI/intro/atag.php 19 NFRs may be expressed in user voice form (or not) Lean Practices for NFR traditional expression All messages shall be displayed in less than one minute All open source software must be approved by the CFO Update mobile app with new logo User voice form As a consumer I want to be notified of any messages from the utility in less than one minute of arrival so that I can take appropriate action quickly As your CFO, I need to make sure we don t use any open source software that I haven t approved, so we don t have license exposure As a product manager, I need to make sure we update the logo to satisfy marketing works, adds value adds some value doesn t add much value 20

11 Development Series Development Series NFRS must also be tested Lean Practices for Often requires specialty skills and tools May also be province of system team Backlog Item Is one of Constrained by 0..* 0..* Compliant when passes Nonfunctional 1..* 0..* System Qualities Tests 1 Feature Realized by 0,1 1..* Done when passes 1..* Acceptance Test Story 1 1 Implemented by 1 1..* Task NFR NFRs in the Agile Testing Matrix Lean Practices for Automated & Manual Manual Automated Tools Source: Brian Marick; Crispen and Gregory: Agile Testing, Leffingwell:

12 Development Series Development Series Sources of Nonfunctional Lean Practices for Source: Wikipedia 23 Persisting Nonfunctional Create a special backlog in your agile project management tool Put them on a wiki or other project repository Build a supplemental specification Include them as an appendix to the Definition of Done for the project Lean Practices for Sources, Examples and Templates: Rational Unified Process Supplemental Specification Leffingwell: : Lean Practices for Teams, Programs and the Enterprise, Addison- Wesley Leffingwell and Widrig [2003] : Managing Software,: A Use Case Approach,, Addison-Wesley

13 Nonfunc'onal in the Big Picture 2009 Leffingwell, LLC. H H H H Lean Practices for Foreword by Don Reinertsen Development Series Today s Exercise: IDENTIFYING AND QUANTIFYING QUALITIES 26

14 Development Series Development Series Today You Will Learn How To Lean Practices for Identify the right qualities Those key qualities that deliver value to the highest priority stakeholders early Quantify them for clarity To ensure stakeholder s desires are clearly understood by everyone 27 Exercise Background Objective Identify highest priority quality improvements for the 2011 Agile Conference Web Site Exercise Identify the highest priority qualities for the most important stakeholders Clearly define these qualities for focused improvements Assumptions At some point during the conference you ve used the current web site You want to help improve the web site Lean Practices for 28

15 Development Series 29 Important Concept: Ends vs. Means Lean Practices for Levels of Concern Organization Product Ends Objectives Means Products, Features Exercise Focus Ends Qualities Design Means Design, Architecture 30

16 Development Series Page 1 Instruc'ons Stakeholders Quali'es 1. Pair up with a partner and spend 2 minutes brainstorming a list of stakeholders Stakeholders are the en..es we re trying to deliver value to by building a product Quali.es reflect how well the product performs, not what func.ons it performs Examples: Usability, Responsiveness 2. Next, with your partner spend 2 minutes iden=fying the top 2 quali=es for improvement for the most important stakeholder Right Qualities for Software Lean Practices for Functionality Features, User Stories, Capabilities, Security Usability Human factors, Aesthetics, Consistency, Documentation Reliability Availability, Recoverability, Accuracy Performance Responsiveness, Throughput, Scalability Supportability Maintainability, Testability, Extensibility, Adaptability, Serviceability, Configurability, Portability, Compatibility Source: FURPS model developed at Hewlett-Packard and documented by Robert Grady and Deborah Caswell in Software Metrics: Establishing a Company Wide Program (1987) 32

17 Development Series Development Series Today You Will Learn How To Lean Practices for Identify the right qualities Those key qualities that deliver value to the highest priority stakeholders early Quantify them for clarity To ensure stakeholder s desires are clearly understood by everyone 33 How to Define a Quality Lean Practices for Step 1 Step 2 Name: In the form Quality.SubQuality Scale: What to measure (units) Meter: How to measure (method) Target: Success level to achieve Constraint: Failure level to avoid Baseline: Current level Optional Elements Definitions: To clarify terminology and meaning [Qualifiers]: Specificity and Reusable Scales <- Sources: Additional transparency and credibility Source: Based on Planguage from Competitive Engineering by Tom Gilb 34

18 Development Series Real Product Examples Step 1 Lean Practices for Name: Usability.Efficiency Scale: Number of Actions to complete a Transaction from a Location Meter: Average observed results from usertesting.com usability tests Name: Usability.Conversion Scale: Percentage of Users who complete a Transaction after starting Meter: Google Analytics conversion report Actions: One of {Data entry, Click, Scroll}. Default is All Actions Transaction: One of {ecommerce [Shop, Purchase], Self Service [Activate, Change Plan]} Location: One of {Home Page, My Account}. Default is Home Page Alternative Syntax Name: Usability Scales: Efficiency: Number of Actions to complete a Transaction from a Location Conversion: Percentage of Users who complete a Transaction after starting Meters: Efficiency: Average observed results from usertesting.com usability tests Conversion: Google Analytics conversion report 35 Page 2 Quality Defini'on Step 1: Iden'fy name, appropriate scale of measure and method of measuring Name: In the form Quality.SubQuality Scale: What to measure (units) Meter: How to measure (method) Step 2: Establish Baseline and set appropriate targets and constraints Name: Scale: Meter: Quality Target: Success level to achieve Constraint: Failure level to avoid Baseline: Current level [Qualifiers]: Specificity and Reusable Scales <- Sources: Addi=onal transparency and credibility Defini'ons: To clarify terminology and meaning Baseline Constraint Target Quality Example Name: Usability.Efficiency Scale: Number of Ac=ons to complete a Transac=on from the Home Page Meter: Average observed results from usertes=ng.com usability tests Ac=ons: One of {Data entry, Scroll, Click}. Default is All. Transac=on: One of {Registra=on, Purchase} Name: Scale: Meter: Quality Baseline [Registra=on; 2010]: 80 [Purchase; 2010]: 60 Constraint [Registra=on; 2011]: 72 <- 10% improvement [Purchase; 2011]: 54 <- 10% improvement Target [Registra=on; 2010]: 48 <- 40% improvement [Purchase; 2010]: 42 <- 30% improvement Baseline Constraint Target

19 Development Series Development Series Baselines Lean Practices for Common methods for establishing Baseline levels include Method Use Existing Meter Create a New Meter Estimate Description Use existing method of measuring such as a report Create a new method of measuring. This requires the team to implement new capabilities in order to measure in the future Do the best you can to estimate what the existing baseline is, even if there s no supporting data. Use the <- source tag to indicate credibility of data 37 Targets and Constraints Lean Practices for Common methods for establishing Target and Constraint levels include Method Improvement from the Baseline Comparison with Leading Competitors Comparison with your Industry Leaders Comparison with other Industry Leaders Description Plan a 20% - 40% improvement over current levels by next year Benchmarking yourself against leading competitors and setting levels based on their capabilities Benchmarking yourself against your industry leaders, such as trying to be in Gartner s Magic Quadrant Benchmarking yourself against other industries known for great levels of quality, such as Nordstrom s customer service 38

20 Development Series Development Series Visualizing Qualities Lean Practices for Baselines, Targets and Constraints exist along a continuum of improvement Constraint Baseline Target Fail Success 0% 30% 100% 39 Real Product Examples Steps 1 & 2 Name: Usability Scales: Efficiency: Number of Actions to complete a Transaction from a Location Conversion: Percentage of Users who complete a Transaction after starting Meters: Efficiency: Average observed results from usertesting.com usability tests Conversion: Google Analytics conversion report Lean Practices for Actions: One of {Data entry, Click, Scroll}. Default is All Actions Transaction: One of {ecommerce [Shop, Purchase], Self Service [Activate, Change Plan]} Location: One of {Home Page, My Account}. Default is Home Page Target: Efficiency [ecommerce; Release 2]: 62 actions <- 40% reduction Conversion [ecommerce; Q Q2 2011]: 0.5% <- 30% increase, industry average Constraint: Efficiency [ecommerce; Release 2]: 93 actions <- 10% reduction Conversion [ecommerce; Q Q2 2011]: 0.43% <- 15% increase Baseline: Efficiency [ecommerce; Release 1]: 103 actions <- Average of 10 usability tests Conversion [ecommerce; Q Q2 2010]: 0.37% <- Current state 40

21 Development Series Page 2 Quality Defini'on Step 1: Iden'fy name, appropriate scale of measure and method of measuring Name: In the form Quality.SubQuality Scale: What to measure (units) Meter: How to measure (method) Step 2: Establish Baseline and set appropriate targets and constraints Name: Scale: Meter: Quality Target: Success level to achieve Constraint: Failure level to avoid Baseline: Current level [Qualifiers]: Specificity and Reusable Scales <- Sources: Addi=onal transparency and credibility Defini'ons: To clarify terminology and meaning Baseline Constraint Target Quality Example Name: Usability.Efficiency Scale: Number of Ac=ons to complete a Transac=on from the Home Page Meter: Average observed results from usertes=ng.com usability tests Ac=ons: One of {Data entry, Scroll, Click}. Default is All. Transac=on: One of {Registra=on, Purchase} Name: Scale: Meter: Quality Baseline [Registra=on; 2010]: 80 [Purchase; 2010]: 60 Constraint [Registra=on; 2011]: 72 <- 10% improvement [Purchase; 2011]: 54 <- 10% improvement Target [Registra=on; 2010]: 48 <- 40% improvement [Purchase; 2010]: 42 <- 30% improvement Baseline Constraint Target Today You Will Learn How To Lean Practices for Identify the right qualities Those key qualities that deliver value to the highest priority stakeholders early Quantify them for clarity To ensure stakeholder s desires are clearly understood by everyone 42

22 Development Series Lean Practices for THANK YOU 43