# Bundles

Bundles are a method of grouping together many data transactions in the Arweave into a single, larger transaction.

Bundles of data items on Arweave have a number of benefits to the systems scalability and usability:

- Bundles allow the extremely large maximum data size (2^256-1 bytes) of Arweave transactions to be split across many individual pieces of data, avoiding the need for excessive numbers of base layer transactions.
- Being a blockchain network, Arweave transactions can occasionally be rejected by the network for a number of reasons. Using data bundles lowers the likelihood that this will become an issue during uploads of datasets containing many files.
- Data entry IDs can be relied upon without waiting for confirmation on the Arweave network, as they can be submitted (and resubmitted) at any time -- unlike normal TXs. This is particularly helpful if you need to refer to a piece of data inside Arweave from a smart contract on another network.

Notably, transactions that move tokens between Arweave wallets _cannot_ be bundled.

You can read more about the intricacies of Arweave bundles in the [spec](https://github.com/joshbenaron/arweave-standards/blob/ans104/ans/ANS-104.md), and get started using them with the [ArBundles](https://github.com/Bundler-Network/arbundles) library.

## Bundlers

Bundled data entries are signed by users, but paid for by the wallet that signs the base-layer Arweave transaction. This allows for the creation of 'bundler' services, which take signed data entries from users, batch them with other user's submissions, then submit them to the network in a single Arweave TX. This enables a number of distinct benefits:

- Users can maintain accounts with bundler services that are paid for in different currencies. For example, a bundler service may let users deposit Bitcoin or a stablecoin on Solana into their wallet, then spend from this balance as they send data netries to be bundled by the service.
- Bundler services can offer instant, guaranteed finality to Arweave data transactions. This is achieved by the bundler taking the burden of handling any potential resubmissions that may be required in order to settle a piece of data into the Arweave network.
- Developers and others may offer open bundler services which pay for the upload of data transactions that match a certain patter n-- for example, interactions with an application they have developed, etc.
- In certain circumstances, bundler services may be able to offer economic guarantees that a data entry sent to the node will be uploaded within a certain time period. These can be used as data availability proofs in a number of situations.

A number of wallet services are presently discussing integration of bundler service support into their offerings, and the first decentralised bundler network -- [Simple.Storage](SimpleStorage) is preparing for launch.