---
title: "Backfill Connection"
method: POST
path: "/v1/sources/{source_id}/backfill"
tags: ["sources"]
---

# Backfill Connection

`POST /v1/sources/{source_id}/backfill`

Fetch all existing records from Nango for a specific connection and ingest them.
This is the per-connection version of backfill for when multiple connections exist.

## Path parameters

- `source_id` string, uuid, required

## Response `200`

Successful Response

- BackfillResponse
  - `fetched` integer, required
  - `ingested` integer, required
  - `filtered` integer
  - `stale_hidden` integer
  - `sync_status` string, nullable
  - `message` string, nullable
  - `filter_stats` object, nullable

## Other responses

- `422` — Validation Error

---

[API](https://skmtc.dev/ontora/apis/ontora-api.md) · [All operations](https://skmtc.dev/ontora/apis/ontora-api/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/ontora/ontora-api/revisions/7f57037fd94b/schema)