# PullSource

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

Defined in: [packages/synapse-sdk/src/types.ts:568](https://github.com/FilOzone/synapse-sdk/blob/bd9e06ee9cf6823545e5c4af63ab47e38bbf43ef/packages/synapse-sdk/src/types.ts#L568)

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