Contract: Implement EVM Paymaster with ERC-4337 Account Abstraction

[Smartdevs17]

Context

ERC-4337 enables smart contract wallets with gas abstraction, batch transactions, and social recovery. AgenticPay should leverage this for superior user experience.

Current Limitation/Problem

AgenticPay currently uses EOA-based wallets. Users must manage private keys and hold native gas tokens. ERC-4337 is not integrated.

Expected Outcome

An ERC-4337-compatible paymaster contract and bundler integration that sponsors gas for user operations, supports batched transactions, and enables session keys for seamless UX.

Acceptance Criteria

• Deploy ERC-4337 EntryPoint compatible paymaster contract
• Implement verification paymaster (pre-signed sponsorship) and deposit paymaster (pre-funded)
• Integrate with existing bundler infrastructure (Stackup, Pimlico, or custom)
• Support batched user operations (multiple actions in one tx)
• Implement session key mechanism for recurring approvals
• Handle gas estimation with paymaster sponsorship
• Dashboard for paymaster budget management and usage analytics
• Fallback to user-paid gas when paymaster unavailable

Technical Scope

• contracts/evm/paymaster/ - Paymaster contracts
• backend/src/services/account-abstraction/ - bundler integration service
• Integration with ethers.js UserOperation handling
• Prisma: PaymasterBudget, UserOperation models
• Edge cases: signature validation failure, deposit exhaustion, operation expiry, entry point upgrades

[Emelie-Dev]

@Emelie-Dev has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hi, I would love to work on this issue.

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[dimka90]

@dimka90 has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Can i work on this?

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