---
title: "work: backfill"
description: "a source, an access method, a window, a plane to the job; then partitions carrying the window"
section: reference
address: /reference/work/backfill
contract: 0476e35e6e275db5
---
# work: backfill
a source, an access method, a window, a plane to the job; then partitions carrying the window
[figure: The caller sends BackfillInput to /v1/work/backfill. The platform returns a card whose body is Job.]
POST/v1/work/backfilla task, 202
Run a backfill. The call needs the brand rung under a token with the work grant, and it is served by the platform.
The route takes [BackfillInput](/concepts/backfillinput) and returns a card whose body is [Job](/concepts/job).
## Request body
The request body is [BackfillInput](/concepts/backfillinput).
| field | type | required | note |
|---|---|---|---|
| `source` | `id` | yes | |
| `access_method` | `id` | yes | |
| `window` | [Window](/concepts/window) | yes | |
| `plane` | [Plane](/concepts/plane) | yes | |
| `reading` | `text` | no | the hash of the procedure reading the backfill runs over, filled by the platform from the newest reading of the source through the way's connector; a caller leaves it empty |
## Response
The route returns a card whose body is [Job](/concepts/job). Every card ends with a foot that states the basis of each number, the scope of the call, and the time when the facts were true. This route runs as a long step and returns a task with status 202. `POST /v1/work/status` returns the task's progress, and `POST /v1/work/cancel` stops the task.
## Headers
| header | required | meaning |
|---|---|---|
| `Scale-Scope` | yes | the scope the call runs in: tenant/, then /brand/, then /strategy/ |
| `Scale-As-True-On` | no | the date the facts must have been true on; defaults to now |
| `Scale-As-Known-On` | no | the date the facts must have been known on; defaults to now |
| `Scale-Key` | no | for a change, the key made from the input; a repeat under the same key returns the unit held and writes nothing |
A caller needs the brand rung and a token with the work grant. The platform serves this route.
## Example
The example sends the smallest body that BackfillInput allows. The build validates it against the schema of BackfillInput.
Example
```sh
curl -X POST https://api.scaleintelligence.co/v1/work/backfill \
-H "Scale-Key: $SCALE_KEY" -H "Scale-Scope: tenant/" \
-H "content-type: application/json" \
-d '{ "source": "…", "access_method": "…", "window": { "from": "…", "to": "…" }, "plane": { "plane": "shared" } }'
```
```typescript
import { client } from "@scale/sdk";
const answer = await client.work.backfill({
"source": "…",
"access_method": "…",
"window": {
"from": "…",
"to": "…"
},
"plane": {
"plane": "shared"
}
});
// answer.body is a Job. answer.foot holds the basis, the scope and the time.
```
```python
import requests
answer = requests.post("https://api.scaleintelligence.co/v1/work/backfill",
headers={"Scale-Key": KEY, "Scale-Scope": "tenant/"},
json={
"source": "…",
"access_method": "…",
"window": {
"from": "…",
"to": "…"
},
"plane": {
"plane": "shared"
}
}).json()
```
```rust
let answer: Card = client.post("https://api.scaleintelligence.co/v1/work/backfill")
.header("Scale-Key", key).header("Scale-Scope", "tenant/")
.json(&BackfillInput { /* the fields of the page */ }).send().await?.json().await?;
```