ZKsync OS Server Developer Documentation

This book guides you through running, understanding, and extending the ZKsync OS Server.

Understanding the System

Deep dives into internal components and lifecycle.

• Database Layout
• State Model
• Merkle Tree Structure
• Genesis Process

Running the System

These guides help you set up and operate the server in different environments.

• Run against Layer 1 (L1) — Local dev chain and Sepolia testnet setup, environment variables, common pitfalls.
• Updating Contracts — Rebuilding and deploying custom contracts, migration flow, testing.