Formal Verification: EVM vs Move

Massive developer leverage: Access to 4,000+ verified contracts on Etherscan and battle-tested tools like Foundry, Hardhat, and Slither. This matters for teams prioritizing rapid deployment, existing Solidity expertise, and integration with DeFi giants like Uniswap and Aave.

Proven security model: Secures over $500B+ in TVL across chains. While not formally verified by default, its extensive audit history and bug bounty programs create a high-cost attack surface. This matters for applications where the security of existing capital and composability is paramount.

Linear type system: Assets are non-copyable and non-double-spendable by design, preventing entire classes of exploits like reentrancy and overflow. This matters for building high-asset-value protocols (e.g., liquid staking, decentralized exchanges) where correctness is non-negotiable.

First-class verifiability: The Move Prover allows specifying functional correctness directly in the source code. Used by Aptos and Sui core protocols. This matters for teams building critical financial primitives (e.g., lending, stablecoins) that require mathematical guarantees beyond manual audits.

Tooling is additive: Formal verification (e.g., Certora, Halmos) is applied after development, requiring extra effort and expertise. This can lead to gaps between the spec and implementation. Choose EVM when ecosystem reach outweighs the need for built-in guarantees.

Smaller network effect: Lower TVL (<$10B combined for Aptos/Sui) and fewer production-tested blue-chip dApps. This matters for projects that depend heavily on existing liquidity, oracles (Chainlink), and cross-protocol integrations.

Specific advantage: Access to battle-tested tools like Certora Prover (used by Aave, Compound), Halmos, and Mythril. This matters for teams with existing Solidity codebases who need to integrate formal verification into their CI/CD pipeline without a full language migration.

Specific advantage: Leverages a pool of 1M+ Solidity developers. This matters for protocol teams with large engineering budgets who need to hire and scale quickly, as they can find developers who already understand the underlying execution model (stack-based VM, 256-bit words).

Specific advantage: The language enforces resource semantics (no double-spending) and linear types at the compiler level. This matters for DeFi and asset-centric protocols (like Aptos' Aries, Sui's DeepBook) where guaranteeing asset conservation is non-negotiable, reducing the verification burden.

Specific advantage: Move Prover is integrated into the toolchain, allowing formal specs to be written alongside the code using the Move Specification Language (MSL). This matters for teams building from scratch who want "correct-by-construction" smart contracts with less reliance on external audit firms.

Specific disadvantage: Formal models must account for complex EVM quirks (e.g., gas, bytecode quirks, all 256-bit operations). This matters because it increases the time and cost of creating accurate specifications, and subtle modeling errors can miss critical vulnerabilities.

Specific disadvantage: ~10k-20k Move developers vs. millions for Solidity. This matters for CTOs with aggressive roadmaps, as hiring experienced Move developers is more difficult and expensive, and the ecosystem of audited libraries (like OpenZeppelin) is less mature.

Established formal verification frameworks: Tools like Certora Prover, Scribble, and Solidity SMTChecker have been battle-tested on protocols like Aave and Compound, securing over $50B in TVL. This matters for teams needing auditor-familiar tooling and a wide range of security service providers.

Unrestricted programming model: Solidity/Vyper allow complex, Turing-complete logic, enabling innovative DeFi primitives like Uniswap V3's concentrated liquidity. This matters for protocols requiring maximum design flexibility, but increases the verification burden and attack surface.

Linear types and ownership semantics: The Move language prevents double-spending, accidental loss, and reentrancy at the compiler level by treating assets as non-copyable resources. This matters for financial applications where asset integrity is non-negotiable, reducing whole classes of bugs.

Bytecode verifier and explicit dependencies: Every Move module is verified for memory safety, type safety, and resource correctness before deployment on Aptos or Sui. This matters for high-assurance systems like on-chain custody (e.g., Pontem Network) where pre-deployment guarantees are critical.

Post-hoc specification burden: Formal verification requires manually writing complex rules and invariants for each contract. This leads to higher cost and longer timelines for audits, as seen with major protocol upgrades requiring months of Certora engagement.

Limited expressiveness for non-asset logic: Move's strict resource model can be cumbersome for complex game logic or social applications, potentially requiring workarounds. This matters for developers building non-financial dApps who may find the paradigm restrictive compared to Solidity.