> For the complete documentation index, see [llms.txt](https://docs.lumia.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.lumia.org/ecosystem/lumia/architecture/interoperability.md).

# Interoperability

**Who this is for:** developers building anything that needs to move a message or an asset between Lumia and another chain. **You should already know:** [Architecture](https://app.gitbook.com/s/chmhPiVNAafGw48c4oU2/ecosystem/lumia/architecture).

### Why an L2 needs interoperability at all

No chain is an island. An asset issued on Lumia, a price feed sourced elsewhere, or a user arriving with funds on Ethereum or another L2 all require some way to move value or information across a chain boundary that neither chain natively understands. "Interoperability" is the umbrella term for the protocols that make that crossing safe: proving that something happened on chain A in a way chain B can verify, without just trusting a third party's word for it.

There are two distinct interoperability surfaces relevant to Lumia. One is general-purpose cross-chain messaging: passing arbitrary messages or assets between Lumia and chains outside the Polygon CDK ecosystem, covered below. The other is the native settlement and bridging Lumia gets automatically from being a member of Polygon's shared AggLayer alongside other CDK chains, covered under [Lumia's chain framework and settlement](https://app.gitbook.com/s/chmhPiVNAafGw48c4oU2/ecosystem/lumia/architecture/polygon-cdk-and-agglayer/the-lumia-chain-framework-and-settlement).

### Cross-chain messaging

For general-purpose messaging outside the AggLayer, Lumia documents an integration with **Hyperlane**, a permissionless interchain-messaging protocol.

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-target data-type="content-ref"></th></tr></thead><tbody><tr><td><strong>Cross-chain messaging with Hyperlane</strong></td><td>How Lumia's Hyperlane integration is documented today.</td><td><a href="https://app.gitbook.com/s/chmhPiVNAafGw48c4oU2/ecosystem/lumia/architecture/interoperability/cross-chain-messaging-with-hyperlane">https://app.gitbook.com/s/chmhPiVNAafGw48c4oU2/ecosystem/lumia/architecture/interoperability/cross-chain-messaging-with-hyperlane</a></td></tr></tbody></table>