Overview

Pure runtime bytecode without constructor or metadata

Type Definition

Branded Uint8Array representing pure runtime bytecode without constructor logic or compiler metadata.

import type { brand } from '@tevm/voltaire/brand';

export type RuntimeCodeType = Uint8Array & {
  readonly [brand]: "RuntimeCode";
};

Runtime code is the actual bytecode executed when calling a contract after deployment. It excludes:

• Constructor logic
• Solidity compiler metadata
• Creation-time initialization

Quick Reference

Create

import * as RuntimeCode from '@tevm/voltaire/RuntimeCode';

// From hex string
const code = RuntimeCode.from("0x6001600155");

// From Uint8Array
const code = RuntimeCode.from(new Uint8Array([0x60, 0x01, 0x60, 0x01, 0x55]));

Compare

// Compare runtime codes
if (RuntimeCode.equals(code1, code2)) {
  console.log("Runtime codes match");
}

// Convert to hex
const hex = RuntimeCode.toHex(code);

API Methods

Constructors

• from(value) - Create from hex string or Uint8Array
• fromHex(hex) - Parse hex string (with or without 0x prefix)

Utilities

• toHex(code) - Convert to hex string
• equals(a, b) - Compare equality

Usage Patterns

Contract Verification

import * as RuntimeCode from '@tevm/voltaire/RuntimeCode';
import * as ContractCode from '@tevm/voltaire/ContractCode';

// Get deployed code and strip metadata
const deployed = ContractCode.from(await provider.getCode(address));
const deployedRuntime = ContractCode.stripMetadata(deployed);

// Compare with compiled runtime code
const expectedRuntime = RuntimeCode.from(compiledRuntimeCode);

if (RuntimeCode.equals(deployedRuntime, expectedRuntime)) {
  console.log("Contract verified: runtime code matches");
} else {
  console.log("Verification failed: runtime code differs");
}

Bytecode Analysis

import * as RuntimeCode from '@tevm/voltaire/RuntimeCode';
import * as Bytecode from '@tevm/voltaire/Bytecode';

const runtime = RuntimeCode.from(runtimeBytecode);

// Analyze runtime code
const analysis = Bytecode.analyze(runtime);
console.log(`Instructions: ${analysis.instructions.length}`);
console.log(`Valid: ${analysis.valid}`);
console.log(`Jump destinations: ${analysis.jumpDestinations.size}`);

// Pretty print
const disassembly = Bytecode.prettyPrint(runtime, {
  showGas: true,
  showStack: true,
});
console.log(disassembly);

Comparing Contract Versions

import * as RuntimeCode from '@tevm/voltaire/RuntimeCode';

// Compare different versions of a contract
const v1 = RuntimeCode.from(contractV1RuntimeCode);
const v2 = RuntimeCode.from(contractV2RuntimeCode);

if (!RuntimeCode.equals(v1, v2)) {
  console.log("Runtime code changed between versions");
  console.log(`v1 hex: ${RuntimeCode.toHex(v1)}`);
  console.log(`v2 hex: ${RuntimeCode.toHex(v2)}`);
}

Related

• ContractCode - Full deployed bytecode
• InitCode - Creation bytecode
• Bytecode - Bytecode analysis tools
• Metadata - Compiler metadata

Specification

• Ethereum Yellow Paper - EVM execution model
• EVM Opcodes - Instruction reference
• Solidity Internals - Contract structure