Overrides & swaps

Overrides and swaps are how the team adjusts the schedule without changing the base rotation order. The base round-robin is always recomputed, so removing an override instantly restores the original assignment.

Add an override (one engineer covers a range)

Use an override when someone needs coverage for a stretch of days — a vacation, a conference, an appointment.

In the UI: open the rotation at /rotations/<rotationId> and click Add override. Pick the covering engineer, the start and end dates, and an optional reason.

Via the API:

curl -X POST http://localhost:3000/api/rotations/<rotationId>/overrides \
  -H "Content-Type: application/json" \
  -H "Cookie: <your-session-cookie>" \
  -d '{
    "startDate": "2026-08-03T00:00:00.000Z",
    "endDate": "2026-08-09T00:00:00.000Z",
    "replacementEngineerId": "<engineerId>",
    "reason": "covering while Ada is out"
  }'

The date range is inclusive. If two overrides cover the same day, the one created most recently wins.

Swap two engineers' shifts

Use a swap when two engineers want to trade upcoming on-call weeks. A swap creates two reciprocal overrides that share a swapGroupId: engineer A's shift is covered by B, and B's shift is covered by A.

In the UI: on /rotations/<rotationId>, click Swap shifts. Choose engineer A and engineer B; each engineer's shift field is a dropdown of that engineer's next two upcoming shifts, nearest one preselected — pick the shift to give up from the dropdown rather than typing a date.

You can also start a swap from the schedule list itself: clicking any row opens Swap shifts pre-filled with that row's engineer as engineer A (that shift as A's) and you (the signed-in user, matched by email to an engineer record) as engineer B, with your own next upcoming shift preselected for B. Adjust either side before submitting.

Via the API:

curl -X POST http://localhost:3000/api/rotations/<rotationId>/swaps \
  -H "Content-Type: application/json" \
  -H "Cookie: <your-session-cookie>" \
  -d '{
    "engineerAId": "<engineerA>",
    "engineerBId": "<engineerB>",
    "dateA": "2026-08-03T00:00:00.000Z",
    "dateB": "2026-08-17T00:00:00.000Z"
  }'

dateA / dateB are any date inside each engineer's shift being traded; the app resolves them to the full periods and builds the two overrides.

Remove an override

In the UI: the Overrides & swaps section on /rotations/<rotationId> lists active overrides — click Remove to delete one.

Via the API: deleting an override restores the base assignment for that range:

curl -X DELETE http://localhost:3000/api/overrides/<overrideId> \
  -H "Cookie: <your-session-cookie>"

To undo a swap, delete both overrides that share its swapGroupId.

Modify or delete from the calendar

Tapping the on-call bar of an overridden or swapped period in the calendar opens an actions dialog:

Modify — opens the change pre-filled: a plain override opens the override form (which saves via PATCH /api/overrides/[id]); a swap opens the swap form pre-filled, and saving replaces the swap's two overrides with a fresh pair.
Delete — removes the override, or, for a swap, both overrides in the group.

(Tapping the bar of a normal, unchanged period still opens the "swap with me" suggestion instead.)

Viewing the result

The schedule table on /rotations/<rotationId> marks any changed period with an override or swap pill. The On-call cell shows the originally scheduled engineer in gray on top; when an override or swap changes who's actually covering, the covering engineer appears below it. The period containing today is highlighted.

Overrides & swaps ​

Add an override (one engineer covers a range) ​

Swap two engineers' shifts ​

Remove an override ​