# PullSource

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

Defined in: [packages/synapse-sdk/src/types.ts:586](https://github.com/FilOzone/synapse-sdk/blob/b36c8f99c6e2a9d4d60368a773e5052e196cb6e5/packages/synapse-sdk/src/types.ts#L586)

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