Merge branch 'main' of github.com:peersky/smart-contract-layers

Author: peersky

README.md

@@ -35,3 +35,56 @@ Contract protecting the implementation only needs to implement a [IERC7746](http
 Drainer contract calls victim number of times defined by Drainer function input.
 
 In the particular implementation rate is limited to 10 transactions per block and can be tested by `pnpm test`
+
+
+## Implementing your layer
+
+Layer contract should only implement simple ILayer interface:
+
+```solidity
+// SPDX-License-Identifier: CC0-1.0
+pragma solidity >=0.8.0 <0.9.0;
+
+interface IERC7746 {
+    /// @notice Validates a function call before execution.
+    /// @param configuration Layer-specific configuration data.
+    /// @param selector The function selector being called.
+    /// @param sender The address initiating the call.
+    /// @param value The amount of ETH sent with the call (if any).
+    /// @param data The calldata for the function call.
+    /// @return beforeCallResult Arbitrary data to be passed to `afterCallValidation`.
+    /// @dev MUST revert if validation fails.
+    function beforeCall(
+        bytes memory configuration,
+        bytes4 selector,
+        address sender,
+        uint256 value,
+        bytes memory data
+    ) external returns (bytes memory);
+
+    /// @notice Validates a function call after execution.
+    /// @param configuration Layer-specific configuration data.
+    /// @param selector The function selector being called.
+    /// @param sender The address initiating the call.
+    /// @param value The amount of ETH sent with the call (if any).
+    /// @param data The calldata for the function call.
+    /// @param beforeCallResult The data returned by `beforeCallValidation`.
+    /// @dev MUST revert if validation fails.
+    function afterCall(
+        bytes memory configuration,
+        bytes4 selector,
+        address sender,
+        uint256 value,
+        bytes memory data,
+        bytes memory beforeCallResult
+    ) external;
+}
+```
+## Protecting with a layer
+
+1. Add layers per your needs (in constructor, initializer etc)
+2. Wrap protected state access with layer modifier (fallback function for proxies)
+
+Reference implementation of [MiddlewareProxy](https://github.com/peersky/smart-contract-layers/blob/main/src/MiddlewareProxy.sol):
+
+