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Documentation Index

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Most Solidity contracts can be deployed and executed without modification. However, some common Ethereum assumptions do not hold and should be addressed explicitly.

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Solidity Version and EVM Assumptions

The execution environment follows standard EVM semantics and supports modern Solidity versions. You can assume:
  • Deterministic EVM execution
  • Standard storage, memory, and calldata behavior
  • ABI encoding and decoding identical to Ethereum
You should not assume:
  • Ethereum-style externally owned accounts
  • A gas price market
  • A synchronous transaction lifecycle
Contracts should be written as if execution is deterministic and replayable, with all user intent explicitly provided as input.

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What Breaks

Certain patterns common in Ethereum contracts are incompatible or unsafe in this environment.
  • ecrecoverEVM addresses do not have private keys (as they are generated using Bitcoin pkscripts). Any authentication logic relying on ecrecover will fail or be meaningless. Use BIP-322 verification via the provided precompile instead.
  • tx.origin Assumptions There is no concept of a user-controlled EOA originating a call chain. Relying on tx.origin for authorization or security checks is unsafe.

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Gas-Price-Based Logic

There is no dynamic gas price, base fee, or priority fee. Contracts that rely on gas price for:
  • Anti-front-running logic
  • Fee estimation
  • Dynamic pricing
will not behave as intended. Execution limits are determined by inscription size, not by runtime bidding.

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What Works Well

Several common contract patterns translate cleanly and predictably. ERC-20 / ERC-721 Logic - Token standards, balances, allowances, and transfers behave as expected. These patterns are well-suited for managing assets within the execution environment. Bonding Curves and AMM-Style Math - Purely deterministic pricing logic works well, especially when combined with Bitcoin transaction introspection for BTC-denominated flows. Vaults and Escrows - Contracts that custody assets under explicit rules, timelocks, or conditional releases are a strong fit, particularly when exits are settled back to base BRC-20 balances. Bitcoin-Aware Contracts via Precompiles Precompiled contracts enable direct interaction with Bitcoin data, including:
  • Transaction inspection
  • Satoshi location tracking
  • Timelock script generation
These capabilities allow contracts to enforce Bitcoin-native constraints that are not possible on Ethereum. As a general rule: If your contract logic is explicit, deterministic, and does not rely on Ethereum-specific account or fee assumptions, it will behave predictably and safely in this environment.