---
title: "Kernel Layer"
path: "/contents/tech/core-protocols/kernel-layer"
version: "1.0.0"
author: "Hydrate"
createdAt: "2026-05-03T09:53:55.665Z"
updatedAt: "2026-05-03T09:53:55.665Z"
---

# Kernel Layer

<Infobox>
| Engine — Kernel |
| Engine Layer |
| `radix-engine` |
| [radixdlt-scrypto](https://github.com/radixdlt/radixdlt-scrypto) |
</Infobox>

## Introduction

The kernel is the lowest layer of the Radix Engine. It manages [substates](/contents/tech/core-concepts/substate-model) (units of persistent state), actors (entities that own substates), invocation semantics, ownership transfer, and execution costing. The kernel knows nothing about resources, blueprints, or roles — those are abstractions provided by the system layer above it. Keeping the kernel deliberately small is what makes the engine's safety properties auditable.

## External Links

- [radix-engine kernel sources](https://github.com/radixdlt/radixdlt-scrypto/tree/main/radix-engine/src/kernel)

- [Substate model (wiki)](/contents/tech/core-concepts/substate-model)