ORIGINAL COMPANY-CONTEXT PRACTICE
Coordinate business-day cutoffs across regions
Original practice scenario inspired by Mitsubishi UFJ Financial Group, Inc.'s public business context; this is not a reported interview question or a description of its internal systems. A synthetic banking workflow processes submissions in several countries. Local holidays and daylight-saving changes affect business-day cutoffs. Design a scheduler and audit record that remains reproducible when calendars are updated.
Written for independent practice using company context; this is not a verified question from a company interview.
A REASONED APPROACH
Model answer.
Treat a business calendar as versioned data rather than embedding fixed UTC offsets in code. Every processing decision should identify the timezone, calendar version, and cutoff rule that produced it.
Work through it
- Represent submission instants in UTC and derive local business dates using a timezone database. Define ambiguous local-time handling explicitly.
- Resolve the next eligible processing window against the selected holiday calendar. Persist that decision and an idempotent job key before dispatching work.
- Test daylight-saving transitions, an exceptional holiday, a calendar correction, and delayed delivery across midnight. Decide whether pending work is recomputed after a calendar revision.
Tradeoffs to discuss
- Precomputed windows simplify scheduling, while dynamic rules adapt more readily to calendar updates. Either approach needs versioned decisions and reconciliation.
Common pitfalls
- Adding twenty-four hours does not always mean the next local business day.
- Replaying with today's calendar can change historical processing decisions.