Technical debt and the cost of the next change · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.
به انگلیسی

Borrowed time and its interest

Computing · Software Engineering · ages 21-22
Name ______________________   Date ____________
  1. Which pair matches the limited software-debt analogy?

    • Principal means added change effort; interest means cleanup work
    • Principal means cleanup work; interest means added change effort
    • Principal means extra testing; interest means the cleanup effort
  2. Changing another hard-coded value automatically reduces the design problem that causes repeated code edits.

    Circle one:   True   False

  3. Both a hard-coded zone update and a table update need checking. Which effort should count as debt overhead?

    • The added effort compared with the table-based process
    • The code-edit time before including required checks
    • The full hard-coded update time, including shared checking work
  4. A developer dislikes a module's naming style. No added effort or plausible future risk is identified. That preference alone establishes technical debt.

    Circle one:   True   False

  5. Cleanup takes 168 minutes and then saves 24 minutes on each affected change. Assume constant savings and no other costs. How many whole changes are needed for saved effort to cover cleanup?

    Answer: ______________

  6. Reducing a duplicated configuration requires 60 minutes of restructuring and 35 minutes of regression checks. Both tasks are necessary. What cleanup effort should the plan include?

    • 60 minutes: omit the planned regression checks
    • 95 minutes: include restructuring and regression checks
    • 35 minutes: omit the planned restructuring work
    • 25 minutes: subtract testing time from restructuring time
  7. A debt problem has no cleanup date yet. Which statement is justified without further evidence?

    • Added effort may recur until the underlying issue is reduced
    • Routine edits gradually repay the cleanup effort
    • The remaining cleanup effort grows with elapsed time
  8. A preview feature uses a hard-coded display label. The team has assessed and accepted its temporary cost and risk. Which record includes ownership and a cleanup trigger?

    • Record the shortcut and assessed risk, but leave cleanup unowned and assume future editors will discover when to act
    • Record only the release deadline and omit the shortcut because its temporary risk has already been accepted
    • Record the shortcut and risk; assign cleanup to Jo after the preview ends, and link the ticket from the code
    • Record the shortcut and risk, assign Jo to it, but explicitly omit any date or event for revisiting the decision
  9. An old importer will retire before any planned imports. No ongoing risk is identified. Cleanup costs more effort than it can save before retirement. What is defensible?

    • Consider retirement instead of cleanup and review if plans change
    • Schedule cleanup before retirement to recover earlier maintenance costs
    • Choose cleanup by comparing the importer's age with replacement components
  10. Cleanup costs 100 minutes. Over the planned work it saves 16 minutes on each of 7 settings updates and 22 minutes on each of 5 imports. Ignore other costs and risks. How many net minutes are saved?

    Answer: ______________

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Answer key

For grown-ups. Fold this page away before handing over the rest.

Borrowed time and its interest W1-mt_iA8-0Qg4ID-s1

  1. Principal means cleanup work; interest means added change effort · Principal represents work to reduce the problem; interest represents added effort from working around it. This is not a literal loan schedule.
  2. False · Updating a value can leave the same hard-coded design in place. Routine maintenance is not automatically cleanup.
  3. The added effort compared with the table-based process · Overhead is the additional work caused by the current design relative to the alternative, not all work common to both.
  4. False · A style preference alone does not identify added future effort or risk caused by the design.
  5. 7 · Divide cleanup effort by saving per change: 168 / 24 = 7 changes.
  6. 95 minutes: include restructuring and regression checks · Include both necessary tasks: 60 + 35 = 95 minutes of cleanup effort.
  7. Added effort may recur until the underlying issue is reduced · The issue may keep adding effort to relevant work. Neither automatic repayment nor a fixed growth law follows.
  8. Record the shortcut and risk; assign cleanup to Jo after the preview ends, and link the ticket from the code · The plan identifies the shortcut and risk, names Jo as owner and uses the end of the preview as the cleanup trigger.
  9. Consider retirement instead of cleanup and review if plans change · Under the stated workload and risk assessment, retirement may avoid cleanup that cannot recover its cost. Revisit the decision if assumptions change.
  10. 122 · The savings are 7 times 16 plus 5 times 22 = 222 minutes. Subtract the 100-minute cleanup: 122 net minutes saved.
Worksheet · LightMySky