diff --git a/src/StdPrecompiles.sol b/src/StdPrecompiles.sol
index 04d4134..64b109d 100644
--- a/src/StdPrecompiles.sol
+++ b/src/StdPrecompiles.sol
@@ -4,6 +4,8 @@ pragma solidity >=0.8.20 <0.9.0;
 import {IActivationRegistry} from "./interfaces/IActivationRegistry.sol";
 import {IPolicyRegistry} from "./interfaces/IPolicyRegistry.sol";
 import {IB20Factory} from "./interfaces/IB20Factory.sol";
+import {ITransactionContext} from "./interfaces/ITransactionContext.sol";
+import {INonceManager} from "./interfaces/INonceManager.sol";
 
 /// @title StdPrecompiles
 /// @notice Address constants for Base's singleton precompiles, each paired with an interface-typed
@@ -12,8 +14,13 @@ library StdPrecompiles {
     address internal constant B20_FACTORY_ADDRESS = 0xB20f000000000000000000000000000000000000;
     address internal constant POLICY_REGISTRY_ADDRESS = 0x8453000000000000000000000000000000000002;
     address internal constant ACTIVATION_REGISTRY_ADDRESS = 0x8453000000000000000000000000000000000001;
+    // EIP-8130 system precompiles, in the 0x8130... (EIP number) namespace.
+    address internal constant NONCE_MANAGER_ADDRESS = 0x813000000000000000000000000000000000aa01;
+    address internal constant TX_CONTEXT_ADDRESS = 0x813000000000000000000000000000000000aa02;
 
     IB20Factory internal constant B20_FACTORY = IB20Factory(B20_FACTORY_ADDRESS);
     IPolicyRegistry internal constant POLICY_REGISTRY = IPolicyRegistry(POLICY_REGISTRY_ADDRESS);
     IActivationRegistry internal constant ACTIVATION_REGISTRY = IActivationRegistry(ACTIVATION_REGISTRY_ADDRESS);
+    ITransactionContext internal constant TX_CONTEXT = ITransactionContext(TX_CONTEXT_ADDRESS);
+    INonceManager internal constant NONCE_MANAGER = INonceManager(NONCE_MANAGER_ADDRESS);
 }
diff --git a/src/interfaces/INonceManager.sol b/src/interfaces/INonceManager.sol
new file mode 100644
index 0000000..a2a2369
--- /dev/null
+++ b/src/interfaces/INonceManager.sol
@@ -0,0 +1,58 @@
+// SPDX-License-Identifier: MIT
+pragma solidity >=0.8.20 <0.9.0;
+
+/// @title INonceManager
+///
+/// @notice Singleton precompile managing the EIP-8130 two-dimensional nonces that enable
+///         concurrent account-abstraction transaction execution. Each `(account, nonceKey)`
+///         channel carries its own independently-ordered sequence nonce. Nonce key `0` is the
+///         protocol nonce; it is held in account state and is not served by this precompile.
+interface INonceManager {
+    /*//////////////////////////////////////////////////////////////
+                                 ERRORS
+    //////////////////////////////////////////////////////////////*/
+
+    /// @notice The precompile was invoked via `DELEGATECALL` or `CALLCODE`.
+    error DelegateCallNotAllowed();
+
+    /// @notice Nonce key `0` is the protocol nonce and is not served by this precompile;
+    ///         read it from account state instead.
+    error ProtocolNonceNotSupported();
+
+    /// @notice Nonce key `0` is reserved for the protocol nonce and cannot be incremented here.
+    error InvalidNonceKey();
+
+    /// @notice The `(account, nonceKey)` channel nonce is already at its maximum value.
+    error NonceOverflow();
+
+    /// @notice An expiring nonce's `validBefore` is outside the allowed `(now, now + maxExpiry]` window.
+    error InvalidExpiringNonceExpiry();
+
+    /// @notice An expiring-nonce replay hash has already been recorded and has not yet expired.
+    error ExpiringNonceReplay();
+
+    /// @notice The expiring-nonce set is full of unexpired entries and cannot accept more.
+    error ExpiringNonceSetFull();
+
+    /*//////////////////////////////////////////////////////////////
+                                 EVENTS
+    //////////////////////////////////////////////////////////////*/
+
+    /// @notice Emitted when the 2D nonce for `(account, nonceKey)` is incremented to `newNonce`.
+    event NonceIncremented(address indexed account, uint256 indexed nonceKey, uint64 newNonce);
+
+    /*//////////////////////////////////////////////////////////////
+                              NONCE QUERIES
+    //////////////////////////////////////////////////////////////*/
+
+    /// @notice Returns the current 2D nonce for `account` at `nonceKey`. A never-used channel
+    ///         reads as `0`.
+    ///
+    /// @dev Reverts with `ProtocolNonceNotSupported` for nonce key `0`.
+    ///
+    /// @param account  Account whose channel nonce is being queried.
+    /// @param nonceKey Non-zero nonce channel to query.
+    ///
+    /// @return The current sequence nonce for the channel.
+    function getNonce(address account, uint256 nonceKey) external view returns (uint64);
+}
diff --git a/src/interfaces/ITransactionContext.sol b/src/interfaces/ITransactionContext.sol
new file mode 100644
index 0000000..d63124b
--- /dev/null
+++ b/src/interfaces/ITransactionContext.sol
@@ -0,0 +1,42 @@
+// SPDX-License-Identifier: MIT
+pragma solidity >=0.8.20 <0.9.0;
+
+/// @title ITransactionContext
+///
+/// @notice Singleton precompile exposing the resolved context of the in-flight EIP-8130
+///         account-abstraction transaction: its sender, payer, and the actor id resolved while
+///         authenticating the sender. On non-EIP-8130 transactions the context is not populated and
+///         the getters fall back to `tx.origin`: `getTransactionSender` and `getTransactionPayer`
+///         return `tx.origin`, and `getTransactionSenderActorId` returns `bytes32(bytes20(tx.origin))`.
+interface ITransactionContext {
+    /*//////////////////////////////////////////////////////////////
+                                 ERRORS
+    //////////////////////////////////////////////////////////////*/
+
+    /// @notice The precompile was invoked via `DELEGATECALL` or `CALLCODE`.
+    error DelegateCallNotAllowed();
+
+    /*//////////////////////////////////////////////////////////////
+                            CONTEXT QUERIES
+    //////////////////////////////////////////////////////////////*/
+
+    /// @notice The resolved sender of the in-flight transaction. Never reverts; returns
+    ///         `tx.origin` outside of an EIP-8130 transaction.
+    ///
+    /// @return The resolved sender, or `tx.origin`.
+    function getTransactionSender() external view returns (address);
+
+    /// @notice The resolved payer of the in-flight transaction, equal to the sender when the
+    ///         transaction is self-paying. Never reverts; returns `tx.origin` outside of an
+    ///         EIP-8130 transaction.
+    ///
+    /// @return The resolved payer, or `tx.origin`.
+    function getTransactionPayer() external view returns (address);
+
+    /// @notice The actor id resolved while authenticating the sender of the in-flight
+    ///         transaction. Never reverts; returns `bytes32(bytes20(tx.origin))` outside of an
+    ///         EIP-8130 transaction.
+    ///
+    /// @return The resolved sender actor id, or `bytes32(bytes20(tx.origin))`.
+    function getTransactionSenderActorId() external view returns (bytes32);
+}