Dependency record template
Dependents, substitution cost, expertise retained, alternatives, and exposure score.
Dependency ledger
Track who now depends on the system, what substitution would cost, which expertise remains, and which capacities are being preserved to keep withdrawal possible.
- 1 Evidence
- 2 Authority
- 3 Decision
- 4 Consequence
- 5 Challenge
- 6 Reconsideration
- 7 Correction acts here
Where it acts
At Correction, one of the seven stages every consequential decision passes through. It tracks what replacing the system would cost, so stopping it stays possible.
Steps
Put the mechanism in motion
3 steps, in order. Check each one off as it is done; the records below show the work was done.
0 of 3 steps complete
Records this mechanism keeps
What a team running this mechanism keeps, and what each record is for.
Exposure score worksheet
How depth of dependence, substitution cost, and correction latency combine into the score.
Preserved capacity register
Capacities kept alive for withdrawal, with owners, budget, and review dates.
Reuse-ready snippets
Copy policy, audit, and incident language
Use these snippets in requirements, audits, and postmortems with the mechanism permalink.
Policy requirement
Policy requirement (MEC-18 Dependency ledger) - Maintain a dependency ledger with dependents, substitution cost, expertise retained, alternatives, and an exposure score. - Name the capacities preserved to keep withdrawal possible, each with an owner. Reference: https://ethotechnics.org/mechanisms/patterns/dependency-ledger
Product requirement
Product requirement (MEC-18) - Exposure score and its inputs are reported alongside reliability metrics. - Changes in dependents or alternatives update the ledger within the review cycle.
Audit evidence checklist
Audit evidence checklist (MEC-18) [ ] Dependents are listed with the consequence of an outage for each. [ ] Substitution cost, expertise retained, and alternatives are recorded and dated. [ ] Preserved capacities have owners and evidence they are still funded.
Postmortem trigger
Postmortem trigger (MEC-18) Trigger review when exposure rises materially without a corresponding change in preserved capacity.
Example usage
Ledger for a scheduling system three years in
One scenario with each part of the mechanism in place.
How it plays out
A hospital records that two departments have retired their manual roster, that the last two schedulers who could rebuild it retire next year, and funds a documented fallback roster as a preserved capacity.
Anti-patterns
Common failure cases and counterfactuals
Each case passes on paper and fails in operation. The counterfactual shows what would have worked.
Reliability as safety
High uptime is read as low risk, while the institution's ability to work without the system quietly disappears.
Counterfactual: Dependence is tracked separately from reliability, with its own score and owners.
Exception: A reliable system can be a safe one; the ledger asks a different question, which is what happens when it is gone.
Ledger without alternatives
Dependents are recorded but substitutes are never checked, so the entry cannot show when the last alternative disappeared.
Counterfactual: Alternatives are rechecked on the review cadence and dated.
Exception: Having no alternative is a legitimate finding as long as it is recorded as one.
Diagnostics for this mechanism
Tools that size the risk this mechanism addresses.
Diagnostic
Delegation audit
Walks a team through one workflow against six questions and returns an exposure score, the permissions nobody can justify, and whether its decisions can be undone. Start here when the system keeps no decision records yet; use the record conformance checker once it does.
Cite this page · v1.2.1 · updated Oct 6, 2026 · CC BY-SA 4.0
APA
Ethotechnics Institute. (2026). Dependency ledger (MEC-18). Ethotechnics Institute. https://ethotechnics.org/mechanisms/patterns/dependency-ledger
MLA
Ethotechnics Institute. "Dependency ledger (MEC-18)." Ethotechnics Institute, 2026, https://ethotechnics.org/mechanisms/patterns/dependency-ledger.
Chicago
Ethotechnics Institute. "Dependency ledger (MEC-18)." Ethotechnics Institute. Oct 6, 2026. https://ethotechnics.org/mechanisms/patterns/dependency-ledger.
BibTeX
@misc{mechanism_dependency-ledger,
title={Dependency ledger (MEC-18)},
author={Ethotechnics Institute},
year={2026},
howpublished={Ethotechnics Institute},
url={https://ethotechnics.org/mechanisms/patterns/dependency-ledger},
version={v1.2.1}
}
RIS
TY - WEB TI - Dependency ledger (MEC-18) AU - Ethotechnics Institute PY - 2026 UR - https://ethotechnics.org/mechanisms/patterns/dependency-ledger ER -