Understanding ERC-5189: Account abstraction via endorsed operations

May 16 2024

Understanding ERC-5189: Account abstraction via endorsed operations

ERC-5189 introduces a new framework for formatting and transmitting data, optimizing how developers handle and engage with crypto and digital assets on the blockchain.

Co-authored by members of the Sequence team Agustín Aguilar, Philippe Castonguay, and Michael Standen, ERC-5189 offers an alternate proposal to ERC-4337. Along with a dedicated page, we've also released a demo and have made the code open-source for developers to test and explore.

This article aims to shed light on this new proposal to advance experimentation and discussion within the web3 developer community, improve existing account abstraction standards, and push the ecosystem forward.

So, what is ERC-5189?

ERC-5189 is a ready-to-use decentralized mempool. ERC-5189 proposes a form of account abstraction that ensures compatibility with existing smart contract wallets.

It provides flexibility for alternative designs while avoiding changes to the consensus layer on the blockchain, making it cheaper, more powerful, convenient, and accessible for developers.  

This proposal introduces the concept of endorser contracts as an alternative to the current structure for AA transactions aligned with the current ERC-4337 format. ERC-5189 moves all of the “meta-logic” associated with transactions to independent contracts called endorsers. Endorser contracts are specific smart contract instances designed to assess the quality of AA transactions. Their evaluation helps bundlers decide whether to retain or discard a transaction in the mempool. They’re never called on-chain, during a transaction, and are free to use. To ensure compatibility with this ERC standard, developers integrating their smart contract wallets must either create and deploy an endorser contract or utilize an existing one that aligns with their wallet's specifications. This approach enhances transaction reliability and streamlines integration without imposing a strict transaction framework. 

ERC-5189 doesn’t change the consensus layer or impose changes on existing smart contract wallets, so developers have no backward compatibility issues and benefit from more flexible design mechanics — and are met with a broader range than competing AA standards.

Key features of ERC-5189

ERC-5189 achieves the primary goal of account abstraction, allowing users to relay smart contract wallet transactions using a decentralized mempool.

ERC-5189 key features

ERC-5189 unlocks the potential of zero-cost account abstraction with:

1. Simpler and more flexible wallets: Wallets have more freedom in how they operate. This ERC avoids restrictions on functionalities, allowing developers to build innovative features.

2. Easy adoption for existing wallets: No changes are required for existing wallets to be compatible. This ensures a smooth transition and avoids disruption for current users.

3. Reduced gas fees for users: Transaction validation happens off-chain, so users don't pay extra gas for this security measure.

4. Safer bundler operations: "Endorser" contracts validate transactions before bundlers include them, minimizing the risk of including malicious transactions.

5. Decentralized and dynamic endorser system: Anyone can create an endorser, fostering competition and innovation. Bundlers can choose reliable endorsers based on a public registry.

Why is ERC-5189 important?

ERC-5189 enables all smart wallets to relay transactions without using a centralized relayer. It ensures smooth communication between wallet developers and mempool operators, allowing them to "understand" if the operations are “healthy” or not. 

While ERC-5189 solves the same challenges as ERC-4337, it proposes a framework with different trade-offs.

ERC-4337 ERC-5189 comparison

"ERC-5189 is a fresh take and alternative to ERC-4337 standard, aimed at keeping "blank slate" freedoms when building smart contract wallets. Although it requires a ​trade-off in operational simplicity for mempool operators, it maintains the adaptability needed to support both previous and current wallets, as well as facilitate the integration of future ideas."

Agustín Aguilar, Head of Research @ Sequence

The future of ERC-5189 and beyond

ERC-5189 represents a significant step forward in the standardization of AA mempools. Sequence has open-sourced ERC-5189’s code for the community and continues to welcome feedback and suggestions to improve.

Developer resources to get started with ERC-5189:

For users on the lookout for more detailed information and updates on ERC-5189, visit the official site and learn more here.


Sequence is the leading all-in-one development platform for integrating web3 into games. Onboard, monetize, grow, and retain players with Sequence’s award-winning technology. From collectibles and ownable rewards to fully on-chain experiences, Sequence’s easy-to-integrate platform solves blockchain complexities, so developers can focus on creative execution and delivering amazing player experiences. Trusted by hundreds of games and thousands of developers. Sequence is backed by Take-Two Interactive, Ubisoft, Xsolla, Bitkraft, Brevan Howard, Coinbase, Polygon, and more. To learn more, please visit: https://sequence.xyz/


Written by

Agustin Aguilar

Director of Blockchain Research at Sequence

Philippe Castonguay

Head of Product @ Horizon Blockchain Games and Sequence

Michael Standen

Senior Smart Contract Engineer @ Sequence

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