Architecture Documentation

Overview

Precompile emulator registry and interface for ox-rollup project.

Registry Design

Core Interfaces

  • PrecompileContext: Execution context with block info, addresses, gas price
  • PrecompileHandler: Interface for precompile implementations
  • PrecompileRegistry: Registry for managing and dispatching to handlers

Implementation

HardhatPrecompileRegistry provides handler registration, lookup, and call delegation.

Handler Contract

ArbSys Handler (0x64)

  • Address: 0x0000000000000000000000000000000000000064
  • Functions: arbChainID, arbBlockNumber, arbBlockHash, arbOSVersion

ArbGasInfo Handler (0x6c)

  • Address: 0x000000000000000000000000000000000000006c
  • Functions: getPricesInWei, getL1BaseFeeEstimate, getCurrentTxL1GasFees

Address Format

Full 20-byte lowercase hex strings for all precompile addresses.

Error Behavior

  • Handler-level: Throws errors for invalid calldata/unknown selectors
  • Registry-level: Returns structured error responses for unknown precompiles
  • Format: { success: false, gasUsed: 0, error: "message" }

Plugin Integration

  • initArbitrumPatch() function for initialization
  • Configuration via ArbitrumConfig interface
  • Registry attached to hre.arbitrumPatch

Testing Strategy

  • Unit tests for core functionality
  • Integration tests for plugin bootstrap
  • Smoke tests for component validation
← PreviousNext →