The Hidden Cost of Forking a 'Secure' Smart Account

A forked smart account is a snapshot in time. Upstream security patches, critical audits (e.g., from OpenZeppelin, Trail of Bits), and EntryPoint upgrades from the core ERC-4337 team are missed. Your "secure" fork becomes a sitting duck for novel attacks that the main branch has already mitigated.

• Attack Surface Widens with each missed update
• Zero-Day Exposure to patched vulnerabilities
• Fragmented Security across the account ecosystem

Smart accounts depend on a decentralized network of bundlers (like Stackup, Alchemy, Pimlico) to submit user operations. A forked account with non-standard validation logic can become incompatible, causing transactions to fail or requiring you to run a custom, centralized bundler—defeating the purpose.

• Network Effects Lost: Default bundlers skip your txs
• Centralization Pressure: Forces proprietary infrastructure
• User Experience Craters with failed transactions

Advanced features like sponsored gas (paymasters) and session keys have complex, interdependent logic. A fork that tweaks core account logic can break integrations with major paymaster providers (like Biconomy, Candide) and invalidate carefully designed security models for key management, leading to locked funds or exploitable permissions.

• Sponsorship Broken: Users can't use gasless tx
• Security Model Unraveled: Custom sessions create new attack vectors
• Ecosystem Isolation from key infrastructure providers

Instead of forking the core account, build audited, minimal modules that plug into established standards. Leverage the Singleton EntryPoint and standard validation functions, and innovate on top via modular extensions (e.g., for recovery, spending limits). This keeps you within the security and compatibility umbrella of the mainnet-tested core.

• Security Inheritance from battle-tested core
• Plug-and-Play with existing bundler/paymaster networks
• Aggregated Audits benefit your module

If a fork is absolutely necessary, implement a continuous integration pipeline that automatically pulls security updates from upstream (e.g., from the official ERC-4337 GitHub). Treat every upstream commit as a critical security patch. Run differential fuzzing against the canonical implementation to catch divergence-induced vulnerabilities.

• Automated Security Sync with upstream
• Differential Fuzzing to detect logic drift
• Mandatory Re-Audit on major upstream merges

Proactively develop and maintain a public compatibility test suite for your modified account. Work directly with bundler providers (Stackup, Alchemy) to ensure your custom validation logic is recognized and processed correctly. This turns a compatibility risk into a collaborative integration, preserving decentralization.

• Provider Buy-In through direct collaboration
• Public Test Nets prove interoperability
• Decentralization Preserved by supporting multiple bundlers

Teams fork a 'battle-tested' Safe or Biconomy account, then write custom modules, unknowingly inheriting zero security guarantees. The base contract's audit is irrelevant; the new attack surface is your custom logic and its interaction with other modules.

• Security is not additive: A 10/10 base + a 5/10 module = a 5/10 system.
• Composability Risk: Your module must be safe when composed with any other module in the user's stack, a combinatorially hard problem.

A healthy ecosystem requires a permissionless module marketplace (like a dApp store), but this creates a massive curation and liability problem. Who audits the 1000th social recovery module?

• Tragedy of the Commons: No single entity is incentivized to audit all modules, leading to systemic risk.
• Liability Vacuum: When a module is exploited, the base account developer (e.g., SafeDAO) faces blame despite no fault, creating legal and reputational risk that stifles innovation.

The only scalable solution is to move verification off-chain. Instead of trusting module code, require a cryptographic proof (ZK or Validity proof) that the module's execution is correct. This transforms security from 'trust the auditor' to 'trust the math'.

• Enforced Correctness: The base account contract only needs to verify a single proof, not understand the module's logic.
• Marketplace Enablement: Permissionless module addition becomes safe, enabling true innovation without systemic risk. Projects like Axiom, RiscZero, and Succinct are building this primitive.

L2s with native account abstraction (Starknet, zkSync Era) are building this future by design. Their VM-level integration allows the protocol to natively validate proofs for custom account logic.

• Protocol-Level Security: Module safety is a property of the L2's proof system, not a fragmented ecosystem audit.
• First-Mover Advantage: These ecosystems will attract high-value DeFi and institutional use cases first, as they solve the trust problem at the base layer.

A forked smart account inherits the original's audit scope, not its security guarantees. The underlying cryptography (e.g., ECDSA, BLS) may be sound, but your specific implementation introduces new attack vectors.\n- Key Risk 1: Unvetted integrations with new bundlers or paymasters create single points of failure.\n- Key Risk 2: Custom modifications to entry point logic can invalidate core security assumptions.

Security requires control or verified delegation. Building your own smart account client (like Safe{Core} or ZeroDev Kernel) ensures you manage the upgrade path and dependency tree. The alternative is using a battle-tested, modular client that abstracts the risk.\n- Key Benefit 1: Direct control over entry point upgrades and signature aggregation logic.\n- Key Benefit 2: Leverage the security budget and bug bounties of established entities like Safe or Etherspot.

A forked account becomes a liability vector for your entire application stack. Every downstream service—bundlers, indexers, gas sponsors—must now adapt to your untested quirks, increasing integration time and failure points.\n- Key Risk 1: Your custom UserOperation mempool logic may be incompatible with public bundlers like Stackup or Alchemy.\n- Key Risk 2: Monitoring and alerting for custom revert reasons becomes your team's full-time job.

An audit on the original ERC-4337 account (e.g., SimpleAccount) is worthless for your fork. The trust boundary shifts from cryptographic primitives to your orchestration layer and module system.\n- Key Risk 1: A re-entrancy guard in the base contract does not protect your newly attached validation module.\n- Key Risk 2: Auditors test specified behavior; your fork's novel use cases are outside that scope by definition.

Adopt the same rigor as Layer 1 or cross-chain bridge teams. This means formal verification for core logic, a robust incident response plan, and a time-locked, multi-sig upgrade path.\n- Key Benefit 1: Formal verification tools like Certora can prove invariants for your specific fork.\n- Key Benefit 2: A staged upgrade process prevents a single bug from bricking all user accounts.

Instead of forking the monolithic account, build or integrate modules that plug into a secure base. Let Safe{Core} Account Abstraction Stack or Rhinestone handle the core security while you innovate on the edges.\n- Key Benefit 1: Composability with an existing ecosystem of auditors, wallets, and tools.\n- Key Benefit 2: Your innovation is upgrade-safe and doesn't put users' primary assets at risk.