> 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/polygon-cdk-and-agglayer/what-the-lumia-chain-is-built-with.md).

# What the Lumia chain is built with

**Who this is for:** developers and operators who want to know exactly what software Lumia's chain runs. **You should already know:** [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).

### The chain framework

Lumia assembles its execution, proving, and bridging stack from standard, interoperable components rather than writing that infrastructure from scratch. The framework it uses to do that is the Polygon Chain Development Kit (CDK). Lumia sets its own configuration on top of it (data-availability mode, proof system, hardware) while reusing proven core software and the same path to Ethereum settlement that every other CDK chain uses. That standardization is also what makes AggLayer membership possible (see [How Lumia settles and bridges to Ethereum](https://app.gitbook.com/s/chmhPiVNAafGw48c4oU2/ecosystem/lumia/architecture/polygon-cdk-and-agglayer/how-lumia-settles-and-bridges-to-ethereum)): CDK chains share enough of a common shape that they can plug into a shared settlement hub.