> ## Documentation Index
> Fetch the complete documentation index at: https://docs.autheo.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Architecture overview

> Overview of Autheo Chain's architecture, including its custom modules, EVM runtime, and NFT license gating system.

Autheo Chain is a Cosmos SDK-based Layer 1 blockchain with a full Ethermint EVM runtime. It extends the standard Cosmos SDK with six custom modules that implement NFT license gating, dual-stream emissions, and EVM-to-Cosmos bridging.

<Columns cols={2}>
  <Card title="System architecture" icon="server" href="/nodes/architecture/system-architecture">
    Core layers, module dependencies, request lifecycle, KV store layouts, and network ports.
  </Card>

  <Card title="Module overview" icon="blocks" href="/nodes/architecture/module-overview">
    The six custom Cosmos SDK modules and how they interact.
  </Card>

  <Card title="License gating" icon="lock" href="/nodes/architecture/license-gating">
    How the x/licensedstaking module enforces NFT license preconditions on all staking operations.
  </Card>

  <Card title="License lifecycle" icon="rotate" href="/nodes/architecture/license-lifecycle">
    The four-state machine (ISSUED → BOUND → ACTIVE → REVOKED) and all transition triggers.
  </Card>

  <Card title="NFT rewards" icon="coins" href="/nodes/architecture/nft-rewards">
    Dual-stream emission model, per-block reward formula, remainder carry, and claiming.
  </Card>

  <Card title="EVM integration" href="/nodes/architecture/evm-integration" icon="ethereum">
    Ethermint EVM runtime, JSON-RPC endpoints, address interoperability, and ERC-721 hooks.
  </Card>
</Columns>