zkSync's Native Account Model is a Silent Threat

Ethereum's Externally Owned Account (EOA) model is a user experience bottleneck. It forces all complexity—gas payments, transaction batching, key management—onto the user and their wallet. This creates a wallet-centric ecosystem where innovation is gated by MetaMask's roadmap and security is limited to seed phrases.

• ~90% of DeFi users rely on EOA-based wallets.
• Billions in value lost annually to seed phrase mismanagement and approval exploits.

zkSync bakes ERC-4337-like functionality directly into the protocol's VM. Every account is a smart contract by default, decoupling transaction execution from fee payment and signature validation. This shifts power from the wallet to the application layer.

• Sponsorship: Apps pay gas for users (see Pimlico, Biconomy).
• Session Keys: Enable one-click gaming and trading.
• Social Recovery: Eliminates seed phrase risk.

On zkSync, the application defines the user experience, not the wallet. A wallet becomes just one of many possible transaction interfaces. This inverts the power dynamic of Ethereum, where wallets are the mandatory gateway.

• Threat to MetaMask: Reduces its role to a simple signer plugin.
• Opportunity for Apps: Enables hyper-optimized UX (e.g., gasless onboarding, batch actions).
• Network Effect: Better apps attract more users, reinforcing the native AA standard.

Once developers build for zkSync's native AA, porting to EOA-chains is a downgrade. Features like sponsored transactions require complex, expensive middleware on Ethereum L1 or other L2s like Arbitrum and Optimism. This creates high switching costs and a unique moat.

• Vendor Lock-In: Native AA is a core protocol feature, not a standard.
• Fragmentation Risk: Different AA implementations across L2s (e.g., Starknet, zkSync) hinder interoperability.

zkSync's ~3.5M AA accounts (as of 2024) demonstrate real adoption. Transaction patterns show ~30% of txns use paymasters (gas sponsorship), a metric negligible on EOA chains. This is the early signal of the asymmetry in action.

• User Growth: Driven by apps offering gasless UX.
• Developer Mindshare: Teams choose zkSync specifically for its AA capabilities.

zkSync isn't just scaling Ethereum; it's re-architecting the stack's power layers. The bet is that superior, app-controlled UX will outweigh the network effects of EOA compatibility. The risk is fragmenting the ecosystem. The winner will be the chain that makes wallets invisible.

• Bull Case: Becomes the standard for next-gen dApps (gaming, social).
• Bear Case: Loses DeFi primitives that rely on wallet-based liquidity (e.g., Uniswap, Aave).

zkSync's native account model bypasses the EVM's state transition function, creating a custom execution environment. This divergence is a breeding ground for subtle, non-obvious bugs that standard security tooling like Slither or MythX cannot audit.

• Audit Surface: Custom precompiles and system contracts like ContractDeployer and MsgValueSimulator are opaque.
• Tooling Gap: Foundry and Hardhat forks behave differently, making local testing unreliable.
• Risk Vector: A single logic flaw in the sequencer's native account handling could invalidate the entire chain's state.

Major DeFi protocols (Uniswap, Aave, Compound) are built for the EVM object model. zkSync's account abstraction forces complex, one-off integrations that are fragile and untested at scale.

• Integration Debt: Each protocol must maintain a separate, high-touch codebase for zkSync, increasing attack surface.
• Oracle Risk: Price feeds from Chainlink or Pyth rely on standard CALL semantics; custom account interactions can introduce latency or failure modes.
• Composability Break: Cross-protocol calls (e.g., flash loan -> swap) can fail in unpredictable ways due to gas abstraction and paymaster interactions.

While all rollups have centralized sequencers, zkSync's architecture makes the operator's role more critical and complex. The sequencer must correctly interpret and order native account abstraction transactions, a task with no fallback.

• Censorship Vector: The sequencer can trivially discriminate based on transaction type or paymaster sponsor.
• Liveness Risk: A bug in the sequencer's custom transaction pool logic could halt the chain, with no community-run node software to fork from.
• Upgrade Risk: System contract upgrades, managed by a multi-sig, can unilaterally change core account semantics, a risk not present in immutable EVM chains.

The only viable mitigation for custom VM risk is exhaustive formal verification, not just audits. zkSync's team must prove equivalence between intended behavior and implementation for all system contracts.

• Required Tooling: Investment in K-framework or similar formal methods to specify the zkSync VM.
• Transparency: Public, verifiable proofs of critical security properties (e.g., no double-spends, guaranteed finality).
• Ecosystem Mandate: Grant programs should fund formal verification of major protocol integrations, not just deployment.

To reduce integration fragility, the ecosystem needs a canonical, open-source bundler and paymaster network. This mirrors how ERC-4337 aims to standardize account abstraction on Ethereum.

• Reference Implementation: A public-good bundler (like Skandha or Alchemy's) for zkSync, reducing protocol integration work.
• Paymaster Audits: Collective security audits for major paymaster contracts (e.g., gas sponsorship, fee abstraction).
• Fallback Mechanism: A standardized escape hatch for protocols to fall back to simple EOAs if AA logic fails.

Long-term, the sequencer must be decentralized and accountable. zkSync must accelerate its roadmap for a decentralized prover network and implement fraud proofs for execution, not just validity.

• Execution Proofs: Extend ZK proofs to cover the correctness of the sequencer's transaction ordering and AA processing.
• Permissionless Proving: A competitive market for provers to challenge invalid state transitions, similar to Optimism's Cannon.
• Timeframe Risk: Without a committed deadline for decentralization, the chain carries permanent systemic risk.