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Bundlers ​

Bundlers are smart contracts designed to let developers group several onchain operations into a single, atomic transaction. Rather than requiring users to complete multiple steps—such as approvals, wrapping, supplying, or borrowing—each as a separate transaction, bundlers allow these actions to be executed together in one go. This approach streamlines the process and helps reduce gas costs.

For building user-facing applications on Morpho, using a bundler is the preferred method.

INFO

To see more details, see the Bundler3 contract reference section.

Why Use Bundlers ​

  • Enhanced Simplicity: Bundlers hide the underlying steps of DeFi operations, letting users perform complex actions—such as opening leveraged positions or making vault deposits—in a single, straightforward transaction.
  • Lower Gas Costs: By executing several operations together, bundlers help minimize total gas expenditure compared to running each step separately.
  • Transactional Integrity: Bundled transactions are all-or-nothing; if any part fails, the whole process is reverted. This ensures users never end up in incomplete or undesirable states (for example, with tokens approved but not deposited).

Key Features & Capabilities ​

Bundlers support a broad set of operations, such as:

  • Managing tokens: Set ERC20 approvals (including via permit or permit2), wrap or unwrap native assets (like ETH to WETH), and transfer tokens.
  • Bend market interactions: Perform supply, supplyCollateral, borrow, repay, and withdraw actions.
  • Bend vault operations: Deposit into or withdraw from any vault that follows the ERC4626 standard.
  • Public Allocator: Initiate reallocateTo to shift liquidity as needed.
  • Claiming rewards: Collect rewards from the Universal Rewards Distributor (URD).
  • Swapping on DEXs: Carry out swaps using built-in DEX aggregators.

WARNING

If Bundler3 is granted token approval, it is capable of executing any transaction on your behalf.

For this reason, you should avoid granting Bundler3 approval—whether through a standard approval or a permit.