---
title: "Run sync pipeline (read → write)"
method: POST
path: "/pipeline_sync"
tags: ["Stateless Sync API"]
---

# Run sync pipeline (read → write)

`POST /pipeline_sync`

Without a request body, reads from the source connector and writes to the destination (backfill mode). With an NDJSON request body, uses the provided messages as input instead of reading from the source (push mode — e.g. piped webhook events).

## Query parameters

- `state_limit` integer — Stop streaming after N state messages.
- `time_limit` number — Stop streaming after N seconds.
- `sync_run_id` string — Optional sync run identifier used to track bounded sync progress.

## Response `200`

NDJSON stream of sync messages

## Other responses

- `400` — Invalid params

## Changes

- **2026-04-20** `1e719ad9a31f` — 1 breaking
  - removed the media type `application/json` from the request body
- **2026-04-20** `8bea86f53f8e` — 1 info
  - added the optional property `oneOf[#/components/schemas/LogMessage]/log/data` to the response with the `200` status
- **2026-04-20** `735e87c5d125` — 5 warning, 5 info
  - removed the request property `state/sync_run/progress/streams/additionalProperties/time_range`
  - removed the optional property `oneOf[#/components/schemas/EofMessage]/eof/ending_state/sync_run/progress/streams/additionalProperties/time_range` from the response with the `200` status
  - removed the optional property `oneOf[#/components/schemas/EofMessage]/eof/request_progress/streams/additionalProperties/time_range` from the response with the `200` status
  - removed the optional property `oneOf[#/components/schemas/EofMessage]/eof/run_progress/streams/additionalProperties/time_range` from the response with the `200` status
  - …6 more
- **2026-04-20** `43c276a91cb0` — 1 info
  - added the new optional `query` request parameter `sync_run_id`
- …earlier changes not shown

[Full history](https://skmtc.dev/stripe/apis/stripe-sync-engine/changes/pipeline_sync/post.md)

---

[API](https://skmtc.dev/stripe/apis/stripe-sync-engine.md) · [All operations](https://skmtc.dev/stripe/apis/stripe-sync-engine/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/stripe/stripe-sync-engine/revisions/b5bd4fac9f3c/schema)