Managing Technical Debt - by Michael Hall
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The document provides an in-depth exploration of technical debt in software development, introducing its definition, implications, and strategies for management. It highlights the different types of technical debt, the cost of neglecting it, and techniques like establishing a debt backlog and adopting a 'makeup story' approach for managing existing debt. Additionally, it presents methods for preventing technical debt and emphasizes the importance of a strong development discipline to ensure long-term project success.
Managing Technical Debt - by Michael Hall
- 1. Michael Hall Three Beacons [email protected] 214.783.3936 Managing Technical Debt Using Agile
- 2. Premise 2 © Three Beacons LLC, 2011 “All known compound objects decay and become more complex with the passage of time. Software is no exception.” www.synerzip.com
- 3. What is Technical Debt? 3 © Three Beacons LLC, 2011 • “Technical Debt” term coined by Ward Cunningham in 1992 • Also called “design debt” • Choosing a design or construction approach that is expedient • But increases complexity and is costlier in the long term www.synerzip.com
- 4. The Debt Metaphor 4 © Three Beacons LLC, 2011 • Use a credit card to obtain something now • Pay for it later - financial debt • Plus interest (short term) (future payment due) (the cost of being able to do this) www.synerzip.com
- 5. Technical Debt 5 • The consequences of: - slapdash architecture - poor design - hasty coding (versus rapid) - lack of quality focus - others? The danger occurs when the debt is not repaid quickly. Every minute spent on not-quite-right code results in interest on that debt. © Three Beacons LLC, 2011www.synerzip.com
- 6. Technical Debt 6 T or F: all technical debt is bad and should be avoided at all costs. © Three Beacons LLC, 2011www.synerzip.com
- 7. Types of Technical Debt 7 © Three Beacons LLC, 2011 An outline to use when discussing technical debt 1. Unintentional 2. Intentional A. Short-term B. Long-term www.synerzip.com
- 8. Types of Technical Debt 8 © Three Beacons LLC, 2011www.synerzip.com
- 9. Technical debt quadrant 9 © Three Beacons LLC, 2011 INTENTIONAL UNINTENTIONAL RECKLESS PRUDENT “We don’t have time to mess with coding standards.” “There is a standard way of doing this?” “We will ship on time and revise the quick fix as our top priority in the next release.” “We now know what to avoid.” * www.synerzip.com
- 10. Technical debt quadrant 10 © Three Beacons LLC, 2011 * Short-term: Only if the commitment is there to schedule, prioritize, and fix soon (e.g. in the next sprint). Long-term: Only if the commitment is there to sponsor projects to resolve the debt. If you must take on technical debt for valid reasons, then “respect the asterisk”. www.synerzip.com
- 11. Cost of Technical Debt © Three Beacons LLC, 2011 11 www.synerzip.com
- 12. Technical Debt - impact 12 “The all too common problem is that development organizations let their debt get out of control and spend most of their future development effort paying crippling interest payments.” - Jeff Atwood, www.codinghorror.com Programming and Human Factors © Three Beacons LLC, 2011 CASE STUDY www.synerzip.com
- 13. • Person • Team • Business Technical Debt – impacts 13 © Three Beacons LLC, 2011 1990 - 2000 2000 - 2010 CASE STUDY www.synerzip.com
- 14. Techniques for PREVENTING Technical Debt © Three Beacons LLC, 2011 14 www.synerzip.com
- 15. 1. Draw the Line 15 © Three Beacons LLC, 2011 Culture shift: • From this day forward … • We no longer allow technical debt! • Only exception: tactical or strategic business justification • Even then, we “respect the asterisk” * www.synerzip.com
- 16. 2. Strong “Definition of Done” •Things to consider: - Coding standards adherence - Code reviews - Static analysis - Dynamic purification - Complexity analysis - Written unit tests - 0 known bugs - 100% test cases pass - Test cases automated - Etc. •Visible for - User Story - Sprint - Release © Three Beacons LLC, 2011 16 www.synerzip.com
- 17. 3. Test-Driven Development TDD: write test, fail the test, then write code to pass the test. Refactor when needed. Develop higher quality streamlined code! © Three Beacons LLC, 2011 17 www.synerzip.com
- 18. 4. Collaborative Designs • Whiteboard sessions on design topics • Leverage collective experience of the team • Wisdom of the crowd • User Design Studio • Less reliance on subject-matter experts • Etc. Increase the chance of an optimal design! © Three Beacons LLC, 2011 18 www.synerzip.com
- 19. Recap • Draw the line! • Strong definition of done • TDD • Collaborative designs © Three Beacons LLC, 2011 19 Use these agile techniques to help prevent technical debt www.synerzip.com
- 20. Techniques for Managing NEW Technical Debt © Three Beacons LLC, 2011 20 www.synerzip.com
- 21. 1. Debt Backlog 21 © Three Beacons LLC, 2011 • Used when technical debt is business justified • Tracks debt by name • Lists work tasks associated with each debt • Includes an estimate • Tracks the commitment to fix schedule • Form: product backlog entries, separate Excel spreadsheet, special designation in defect DB, tool entry, sticky notes, etc. • Helps to keep the debt service level visible! Track the debt as you go! www.synerzip.com
- 22. Debt Backlog - example 22 © Three Beacons LLC, 2011 Debt Backlog - My Natural Healer iPhone App Debt Business Justification Sprint Incurred Estimate Work Items Commitment Note Variable names preceded with "email" even though email is only part of their use Confusion factor is not currently there, but will be in the future. sprint 2 1week Change variable names to more meaningful names. sprint 3 DONE Duplicate code for displays in Remedy Controller and Favorites view Meet early May release schedule, willing to accept cost of double maintenance for now. sprints 3- 4 3weeks New file to contain common methods for remedy display, change existing code to conform Release 1.1- expected out in July 2010 Servicing this debt may push the SEARCH function out to a later release. The same method handles both designating and undesignating a favorite Too risky to do right before the customer milestone demo sprint 6 2weeks Bust out undesignate into separate method, add logic to parts of code to know which method to invoke Sprint 7, possibly sprint 8 www.synerzip.com
- 23. 2. Automatic Payment Plan 23 © Three Beacons LLC, 2011 •Pay as you go •Slow team’s velocity down to service the debt as it is incurred •Include technical debt items in upcoming sprints • As quickly as feasible • In line with fulfilling commitment made when debt was justified Service the debt as you go! Keep it as close to $0 as possible. www.synerzip.com
- 24. 3. Makeup Stories 24 • “Makeup”: a story that apologizes to the code base - And promises to fix it! • Placeholder indicating non-user story work - For when you incur technical debt - For any reason you circumvented quality - Use a different color card (red or pink is good) • Add it to the product backlog • Prioritize into next sprint (if possible) Good way to track technical debt. © Three Beacons LLC, 2011www.synerzip.com
- 25. Makeup Stories - example 25 © Three Beacons LLC, 2011 Who Description Estimate (Hours) Remaining (Hours) Notes User login Chris Login window 8 4 Hide password 2 2 John Verify login id is correct 16 0 i/f with Security system John Verify password is correct 16 12 i/f with Security system Alert and log if incorrect 8 8 Chris Block after 3 incorrect tries 24 0 Log occurrence to "watch file" Launch main window if correct 4 4 Refactor and improve Connection Timeout Technical debt item Mona Framework services API change 8 2 Mark Adjust code to use system timers 40 20 Display main window Bala, Tim Query DB for video connections 32 0 Bala to do DB arch Tim Establish connections 16 16 Display sub-tiles according to user config 64 64 Research competition Identify main competitors 40 40 Paul Gap analysis 120 80 Document and share market differentiators 80 80 Amy Brief marketing and sales teams 16 0 Total hours 494 332 Total relative points from product backlog 43 43 www.synerzip.com
- 26. 4. Adopt a Debt! 26 User Story Makeup Story © Three Beacons LLC, 2011 Good way to insure that makeup stories get worked. • “Adopt” approach • If a user story leverages the debt area, “adopt” the debt card as part of the user story effort • Add the makeup story estimate into the user story www.synerzip.com
- 27. 5. Dedicated Sprint to Service Debt 27 © Three Beacons LLC, 2011 • Similar to a “bugfix sprint” • Do this only if really needed - Preponderance of business debt occurring during project - Team concerned about debt growth - Upcoming features rely on code that has debt • Or, combine for a bugfix/debt sprint Periodically pay down your debt throughout the project! www.synerzip.com
- 28. Recap • Debt backlog • Service the debt commitment • Makeup stories • Adoption • Dedicated debt sprint © Three Beacons LLC, 2011 28 Use these agile techniques to manage new technical debt www.synerzip.com
- 29. Techniques for Managing LEGACY Technical Debt © Three Beacons LLC, 2011 29 www.synerzip.com
- 30. 1. Re-Do Project 30 © Three Beacons LLC, 2011 • Business decides on a total re-design and re-write • Happens rarely, hard to justify • Hard for execs to see the value • Often timed with new technology introduction • How to insure that the new system is really better? - Rigorous quality plan - Strong Definition of Done - Iterative development - Feedback loops - Inspect & adapt - Watchful eyes Not an answer: “better people” www.synerzip.com
- 31. 2. “Small Chunks” Approach • Smaller chunks of effort • In conjunction with normal dev flow • Can work well across an API abstraction • Often requires an architectural assessment • Can require code changes to other parts of legacy base (risky) • Happens more often than Re-Do projects • Must insure end result is worth the effort! © Three Beacons LLC, 2011 31 www.synerzip.com
- 32. 3. 70/30 Rule 32 • 70% - new user stories • 30% - paying down the debt of a legacy system • Rule can also be used to manage new technical debt • Helps to have a PO with history of the legacy system • Socialize that legacy improvements are part of this project! - Ask for commitment - Ask to be held accountable - Do your part - Ask others to continue the tradition 70 30 © Three Beacons LLC, 2011www.synerzip.com
- 33. 4. “While There” Rule • While adding a new feature • Any legacy function modified for the feature must be rewritten according to quality plan - Variable names - Coding guidelines - Braces alignment - Etc. • Works well for support team also (while fixing bugs) • CAUTION: may introduce bugs Final thought on case study: • We improved almost 50% of the 4M LOC • Significant drop in critical defects reported from customers • But, we introduced at least 10 new bugs on existing functionality • Each time – required additional justification to continue the effort © Three Beacons LLC, 2011 33 www.synerzip.com
- 34. Recap • Re-Do project • Small chunks approach • 70/30 rule • “While there” rule © Three Beacons LLC, 2011 34 Use these agile techniques to manage legacy technical debt www.synerzip.com
- 35. Conclusion © Three Beacons LLC, 2011 35 www.synerzip.com
- 36. 36 © Three Beacons LLC, 2011 “Developers know their code has technical debt, but they feel powerless to stop adding to it.” – David Rooney, “Technical Debt: Challenging the Metaphor” A Sobering Thought There is hope – using Agile. www.synerzip.com
- 37. 37 © Three Beacons LLC, 2011 “Take my advice: go well, not fast. Care about your code. Take the time to do things right. In software, slow and steady wins the race; and speed kills. – Robert C. Martin (Uncle Bob), president of Object Mentor and agile methods author Managing Technical Debt - conclusion www.synerzip.com
- 38. Good References 38 © Three Beacons LLC, 2011www.synerzip.com
- 39. Questions? www.synerzip.com Hemant Elhence, [email protected] 469.322.0349 Agile Software Product Development Partner 39 www.threebeacons.com Short/Long term Agile coaching Facilitated improvement Agile Methods training: Scrum Team Training Agile / Scrum User Stories – Requirements w/ Agility Product Owner Role ScrumMaster Role Etc. All courses can be delivered onsite at your location Michael Hall, [email protected] 214.783.3936 www.synerzip.com © Three Beacons LLC, 2011
- 40. Confidential Synerzip in a Nut-shell 1. Software product development partner for small/mid- sized technology companies Exclusive focus on small/mid-sized technology companies, typically venture-backed companies in growth phase By definition, all Synerzip work is the IP of its respective clients Deep experience in full SDLC – design, dev, QA/testing, deployment 2. Dedicated team of high caliber software professionals for each client Seamlessly extends client’s local team, offering full transparency Stable teams with very low turn-over NOT just “staff augmentation”, but provide full mgmt support 3. Actually reduces risk of development/delivery Experienced team - uses appropriate level of engineering discipline Practices Agile development – responsive, yet disciplined 4. Reduces cost – dual-shore team, 50% cost advantage 5. Offers long term flexibility – allows (facilitates) taking offshore team captive – aka “BOT” option www.synerzip.com © Three Beacons LLC, 2011
- 41. Confidential Synerzip Clients www.synerzip.com © Three Beacons LLC, 2011
- 42. Thank You! www.threebeacons.com Michael Hall [email protected] 214.783.3936 www.synerzip.com Hemant Elhence [email protected] 469.322.0349 Agile Software Product Development Partner Call Us for a Free Consultation! 42www.synerzip.com © Three Beacons LLC, 2011