# PullSource

> **PullSource** = `string` \| ((`pieceCid`) => `string`)

Defined in: [packages/synapse-sdk/src/types.ts:591](https://github.com/FilOzone/synapse-sdk/blob/d2725be576fc57fac19e7c64cd8e004e0cec85d3/packages/synapse-sdk/src/types.ts#L591)

Source for pulling pieces from another provider.
Either a base URL string or a function that returns a piece URL for a given PieceCID.