Body of Knowledge · Techniques and Models
Debt as interest
Shipping expedient code is like borrowing. It lets you move faster now, and you pay interest on every later change until the principal is repaid. The metaphor turns expedience from a one-off into a running cost.
Evidence grade: practice A widely adopted practitioner model with clear provenance.
Use it when
Explaining debt to anyone; pricing it in terms of delivery.
Where it stops working
It invites the wrong argument. Not all debt should be repaid, and the metaphor says nothing about which.
Where the standard uses it
- TJ-2Technical debtRecognising, quantifying, and scheduling repayment.
Sources
- Ward Cunningham. The WyCash Portfolio Management System. OOPSLA '92 Experience Report, ACM, 1992. In the bibliography
Used alongside it
- Continuous incremental repayment practice
- Elevation to business risk practice
- Systemic risk signals practice
- The technical-debt quadrant practice
Cite this model
Chicago, BibTeX and licence →Engineering Management Academy. (2026). Debt as interest. In Engineering Management Academy Body of Knowledge (Version 3.1, TEC.debt-as-interest). https://www.engineeringmanagement.academy/body-of-knowledge/techniques/debt-as-interest