nrml
Stateful simulationInstacart

Bus Simulation: Keep Boarding Fair and Capacity Accurate

Trace passenger state, repair same-stop capacity, and add priority and wheelchair boarding.

The scenario

Trace passenger state, repair same-stop capacity, and add priority and wheelchair boarding.

A failure to reason about

Use a small stateful simulation scenario to compare current behavior with the requirement.

Illustrative context for the topic. The exercise’s full requirements arrive in the workspace.

Questions to bring to your review

  • Which caller makes the reported behavior visible?
  • What focused regression would distinguish the current behavior from the requirement?
  • What existing behavior must remain intact after the change?

Skills you will practice

  • State transitions
  • Stable ordering
  • Resource accounting
  • Trace-driven debugging

Read the existing code, reproduce the reported behavior, review proposed changes, and verify your final implementation. You can use AI assistance while staying responsible for the result.

Prepare with a worked example

See how nrml evaluates an attempt, including the limits of automated evidence.