Calculate the cancellation window from the booked service policy
A policy update changes the cancellation deadline for appointments sold under yesterday's terms.
- Focused work estimate
- 2h 30m + prerequisites
- Priority in the scenario
- Medium
- Engineering practice
- Versioning · Business rules
Estimated field mix
- Backend100%
Field percentages are editorial estimates of the ticket's engineering focus. They total 100%; they are not measured time, proficiency scores, or ownership evidence.
Review it, then add it to your workspace.
The board opens an editable draft; nothing is saved until you confirm it. Sign-in and workspace permissions apply, and Demo boards remain ephemeral.
Project context
A fictional equipment service books maintenance visits. Expiring checkout holds and reschedules occasionally double-book a technician.
Setup prerequisites
- Build synthetic technicians, slots and booking records.
- Use an injectable clock and separate clients for concurrency probes.
Preceding work
Complete these dependencies, or supply their agreed outputs before taking this ticket.
Acceptance criteria
- Booking retains the applied policy version.
- Deadline calculation uses that frozen policy and UTC start.
- Cancellation returns the policy version and eligibility reason.
Implementation constraints
- This exercise models eligibility only, without charging money.
Verification to include
- Cancel bookings created under two policy versions.
- Change the current policy and verify old booking deadlines remain fixed.
Deliverables
- Versioned cancellation calculator
Rollout and recovery
Publish a new policy version for new bookings; keep historical policy references intact.
Value of the work
For the engineer: Practice resource allocation, interval conflicts and durable workflows.
For the team: Review scheduling correctness and recovery before exposing scarce capacity.
Evidence boundaries
Outcome Evidence: Tests, patches, and runbooks are requested deliverables. They become Outcome Evidence only through a qualified Mission and immutable Evidence IDs.
Ownership Evidence: Independent adaptation must be observed under a declared verification policy and cite immutable Evidence IDs. Completing a planning ticket establishes no Ownership Evidence.