> For the complete documentation index, see [llms.txt](https://docs.on.nexus/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.on.nexus/hodifi/core-system-specifications/system-architecture.md).

# System Architecture

HodlFi's architecture is designed to be trust‑minimized and secure across both the Bitcoin and Ethereum (or other EVM) networks. It is organized in two layers: a contract layer that defines cross‑chain agreements, and a component layer that defines the roles of participants and off‑chain agents. This section highlights the structure, roles, and security boundaries, leaving time‑sequence details to the Loan Lifecycle.