# PullSource

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

Defined in: [packages/synapse-sdk/src/types.ts:619](https://github.com/FilOzone/synapse-sdk/blob/2e357180d354970e2a091ff7ef0f3021c8357d4f/packages/synapse-sdk/src/types.ts#L619)

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