hardScenarioDesignMidSeniorStaff
Your routing optimiser produces a good plan and the transport planner changes it every morning. What is going wrong?
4 min readUpdated 2026-08-15
Answer
Short answer
Usually nothing is wrong with the solver: it is optimising against a model missing constraints the planner knows and never told it, so the plan is optimal and unrunnable.
Was this answer helpful?
Likely follow-ups
- How would you capture why a planner changed something without slowing them down?
- A customer will not accept deliveries before ten. Hard or soft constraint?
- The solver has ninety seconds. What do you give up?
- How would you prove the new plan is actually better?
Related questions
- Vehicle routing is NP-hard. How do you produce a plan the depot will run tomorrow morning?hardAlso on vehicle-routing and optimisation7 min
- Your team says the database is backed up nightly. How would you establish whether you could really restore it?hardAlso on operations5 min
- Every table in this schema soft-deletes with a deleted_at column. A year in, what has that cost you?mediumAlso on constraints5 min
- Six months after launching an internal developer portal, weekly active usage has plateaued at around forty percent of engineering. How would you go about figuring out why, and what would you actually do about it?hardAlso on adoption4 min