codess prague - agile vs traditional methods - apr 2014
DESCRIPTION
Introduction to Agile and Scrum. Comparison to traditional Waterfall method.TRANSCRIPT
Silvana WasitovaAgile & Scrum CoachApril 2014
Agile vs Traditional Methods
How Computer “Geeks” replaced Computer Girls
http://gender.stanford.edu/news/2011/researcher-reveals-how-%E2%80%9Ccomputer-geeks%E2%80%9D-replaced-%E2%80%9Ccomputergirls%E2%80%9D
3
http://www.projectcartoon.com/
64% implemented features are rarely or never used
Ref: Jim Johnson, Chairman of Standish Group, quoted in 2006 in: http://www.infoq.com/articles/Interview-Johnson-Standish-CHAOSSample: government and commercial organizations, no vendors, suppliers or consultants
Rarely19%
Never45%
Always7%
Often13%
Sometimes16%
Waterfall, Agile and Scrum: CharacteristicsWhen is a project a “Scrum Project” and when is it not?
Apr 7, 2023 8
Waterfall Agile : Iterative Development
RUP DSDM
Upfront, Detailed
Emergent Design
Linear hand-offs: Dev then QA
Cross-functional & collaborative: Dev & QA
Formal process, implemented at end
Welcomed, prioritized vs. backlog
At beginning and at delivery Throughout cycle
Scrum• Daily “standup” status checks ≤
15mins• Delivery rhythm in iterations (Sprints)• Demo & Retrospective at end of ea.
Sprint Continuous Improvement
XP: eXtreme Programming
• Automated Tests• Pair Programming• Automated / Continuous Builds• TDD: Test-Driven Development• Continuous Deployment
Teamwork
Change Requests
Customer / User Involvement
Specifications
Scrum is the most popular Agile method: 74% of Agile practitioners (2009)
© Silvana Wasitova
Scrum vs. Waterfall: Time To Market
Develop & QASpec
Develop & QASpec
Scrum
Waterfall
12 weeks 3-6 wksy wks
9 weeks
3 months
6-10 months
CollaborativeResults-Oriented
3 MONTHS
x wks
Updates
Sequential Process-Oriented
6-10 MONTHS
Faster Time to Market Higher Quality Satisfied Customer
Scrum Framework: Summary
Product Owner Team Scrum Master
Planning: Product & Sprint
Daily Scrum Sprint Review &
Retrospective
Product Backlog Sprint Backlog Potentialy
Shippable Product
Roles(Who)
Practices(How)
Artifacts(What)
Cardinal Rule: Work on the highest priority item first
Why Scrum works:
1. Close collaboration with Customer2. Transparency through daily reviews → risk reduction3. LEAN ‘flow’ → frequent delivery of business value4. Eliminate waste, focus on highest priorities5. Inspect, adapt, improve - in each iteration
from Shingo's “Seven Wastes of Manufacturing”
7 Wastes of Software Development
Partially Done Work (In-Process Inventory)
Defects (Defects)
Relearning (Extra Processing)
Extra Features (Over-Production)
Handoffs (Transportation)
Delays (Waiting)
1
2
3
4
5
6
7
Every bit of code that is there and not needed creates complexity that will plague the code base for the rest of its life Task Switching (Motion)
Ref: Implementing Lean Software Development: From Concept to Cash Mary Poppendieck
Lean, Agile, Scrum: How they relateTwo things in common: Eliminate Waste & Increase Customer ValueWaste: anything which does not advance the process, or add value Value: any action or process that a customer would be willing to pay for
• A production practice that considers the expenditure of resources for any goal other than the creation of value for the end-customer to be wasteful, and thus a target for elimination.
• Agile practices are rooted in lean philosophy.
•Scrum is the most popular Agile methodology used in software development.
•Scrum emphasizes iterative approach to building incremental business value.
•Agile is a group of methodologies based on iterative and incremental delivery, where requirements and solutions evolve through collaboration between clients and self-organizing, cross-functional teams.
•Agile practices include: Scrum, Kanban, XP (eXtreme Programming), TDD (Test Driven Development), RUP (Rational Unified Process from IBM).
Lean ScrumAgile
Adapt to changing requirements throughout dev. cycle
Continuous improvement via Retrospectives
Early product delivery
Transparency: daily standup
Stress collaboration between developers and customers
Strip-off non-essential activities & artifacts
Regular reviews with Client/Product Owner
Agile Philosophy
1
2
3
4
5
6
7
•Specifications will never be fully understoodZiv’s Law:
•The user will never be sure of what they want until they see the system in production (if then)
Humphrey’s Law:
•An interactive system can never be fully specified, nor can it ever be fully tested
Wegner’s Lemma:
•Software evolves more rapidly as it approaches chaotic regions (without spilling into chaos)
Langdon’s Lemma:
Agile deals with:
“There is nothing so useless as doing efficiently that which should not be done at all.” ~Peter Drucker
frequent handovers, separating decision-making from work –interfere with the learning that is the essence of development.
Interfering with the smooth flow of value – e.g.: task switching, design loopbacks, technical debt, backlogs – cause organizations to deliver less value while using increasingly more resources.
in software development
Three Biggest Sources of Waste
Building the Wrong Thing
Thrashing.
Failure to Learn
http://www.poppendieck.com/
Silvana Wasitova, CSM, CSP
Lausanne, [email protected]
+41 79 558 05 09slideshare.com/wasitova
Go get it!
21THANK YOU!