Mini EVM in Rust

A minimal Ethereum Virtual Machine (EVM) implementation written in Rust.

This project demonstrates:

• Bytecode parsing
• Stack-based execution
• Arithmetic opcodes
• Stack manipulation opcodes
• Program counter management
• Minimal EVM runtime loop

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Supported Opcodes

Opcode	Hex	Description
STOP	0x00	Halts execution
ADD	0x01	Addition
MUL	0x02	Multiplication
SUB	0x03	Subtraction
DIV	0x04	Division
POP	0x50	Removes top stack item
PUSH1	0x60	Pushes 1 byte to stack
DUP1	0x80	Duplicates top stack item
SWAP1	0x90	Swaps top two stack items

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Project Structure

src/
├── main.rs
└── vm/
    ├── mod.rs
    ├── evm.rs
    ├── stack.rs
    ├── opcodes.rs
    ├── executor.rs
    └── tests.rs

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Installation

Clone the repository:

git clone <repo-url>
cd evm-rs

Install dependencies:

cargo build

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Running the EVM

Example bytecode:

0x6001600201

This translates to:

PUSH1 0x01
PUSH1 0x02
ADD

Run:

cargo run -- 0x6001600201

Expected output:

PC: 0, Opcode: 0x60
PC: 2, Opcode: 0x60
PC: 4, Opcode: 0x1

Execution Finished
Final Stack Top: 3

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Running Tests

cargo test

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EVM Architecture

The VM contains:

• Program Counter (pc)
• Stack
• Bytecode
• Halt flag

Execution flow:

1. Read opcode
2. Execute opcode
3. Advance program counter
4. Repeat until STOP or bytecode ends

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Future Improvements

• PUSH2 → PUSH32
• Memory support (MLOAD, MSTORE)
• Storage support
• Gas accounting
• JUMP/JUMPI support
• CALL opcode support
• Better error handling
• Full EVM compliance

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Learning Goals

This project helps understand:

• Ethereum internals
• Stack-based virtual machines
• Bytecode interpretation
• Rust systems programming
• Smart contract execution