# PullSource

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

Defined in: [packages/synapse-sdk/src/types.ts:591](https://github.com/FilOzone/synapse-sdk/blob/290ea0fe443c3dccbbd3dfb921f7095349eccd59/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.