diff --git a/packages/world/mud.config.ts b/packages/world/mud.config.ts
index 79b98bf596..9003aa683e 100644
--- a/packages/world/mud.config.ts
+++ b/packages/world/mud.config.ts
@@ -48,7 +48,7 @@ export default mudConfig({
         delegatee: "address",
       },
       schema: {
-        delegationControl: "address",
+        delegationControl: "bytes32",
       },
     },
     /************************************************************************
diff --git a/packages/world/src/Call.sol b/packages/world/src/Call.sol
deleted file mode 100644
index 5051102bf4..0000000000
--- a/packages/world/src/Call.sol
+++ /dev/null
@@ -1,90 +0,0 @@
-// SPDX-License-Identifier: MIT
-pragma solidity >=0.8.0;
-
-import { ResourceSelector } from "./ResourceSelector.sol";
-import { WorldContextProvider } from "./WorldContext.sol";
-import { AccessControl } from "./AccessControl.sol";
-import { ResourceSelector } from "./ResourceSelector.sol";
-import { ROOT_NAMESPACE } from "./constants.sol";
-
-import { IWorldErrors } from "./interfaces/IWorldErrors.sol";
-import { ISystemHook } from "./interfaces/ISystemHook.sol";
-
-import { FunctionSelectors } from "./modules/core/tables/FunctionSelectors.sol";
-import { Systems } from "./modules/core/tables/Systems.sol";
-import { SystemHooks } from "./modules/core/tables/SystemHooks.sol";
-
-library Call {
-  using ResourceSelector for bytes32;
-
-  /**
-   * Call a contract with delegatecall/call and append the given msgSender to the calldata.
-   * If the call is successfall, return the returndata as bytes memory.
-   * Else, forward the error (with a revert)
-   */
-  function withSender(
-    address msgSender,
-    address target,
-    bytes memory funcSelectorAndArgs,
-    bool delegate,
-    uint256 value
-  ) internal returns (bytes memory) {
-    // Call the target using `delegatecall` or `call`
-    (bool success, bytes memory data) = delegate
-      ? WorldContextProvider.delegatecallWithContext(target, funcSelectorAndArgs, msgSender) // root system
-      : WorldContextProvider.callWithContext(target, funcSelectorAndArgs, msgSender, value); // non-root system
-
-    // Forward returned data if the call succeeded
-    if (success) return data;
-
-    // Forward error if the call failed
-    assembly {
-      // data+32 is a pointer to the error message, mload(data) is the length of the error message
-      revert(add(data, 0x20), mload(data))
-    }
-  }
-
-  /**
-   * Call the system at the given namespace and name and pass the given value.
-   * If the system is not public, the caller must have access to the namespace or name.
-   */
-  function viaResourceSelector(
-    address caller,
-    bytes32 resourceSelector,
-    bytes memory funcSelectorAndArgs,
-    uint256 value
-  ) internal returns (bytes memory data) {
-    // Load the system data
-    (address systemAddress, bool publicAccess) = Systems.get(resourceSelector);
-
-    // Check if the system exists
-    if (systemAddress == address(0)) revert IWorldErrors.ResourceNotFound(resourceSelector.toString());
-
-    // Allow access if the system is public or the caller has access to the namespace or name
-    if (!publicAccess) AccessControl.requireAccess(resourceSelector, caller);
-
-    // Get system hooks
-    address[] memory hooks = SystemHooks.get(resourceSelector);
-
-    // Call onBeforeCallSystem hooks (before calling the system)
-    for (uint256 i; i < hooks.length; i++) {
-      ISystemHook hook = ISystemHook(hooks[i]);
-      hook.onBeforeCallSystem(caller, systemAddress, funcSelectorAndArgs);
-    }
-
-    // Call the system and forward any return data
-    data = Call.withSender({
-      msgSender: caller,
-      target: systemAddress,
-      funcSelectorAndArgs: funcSelectorAndArgs,
-      delegate: resourceSelector.getNamespace() == ROOT_NAMESPACE, // Use delegatecall for root systems (= registered in the root namespace)
-      value: value
-    });
-
-    // Call onAfterCallSystem hooks (after calling the system)
-    for (uint256 i; i < hooks.length; i++) {
-      ISystemHook hook = ISystemHook(hooks[i]);
-      hook.onAfterCallSystem(caller, systemAddress, funcSelectorAndArgs);
-    }
-  }
-}
diff --git a/packages/world/src/Delegation.sol b/packages/world/src/Delegation.sol
index 3b149b1898..c4140ea0d7 100644
--- a/packages/world/src/Delegation.sol
+++ b/packages/world/src/Delegation.sol
@@ -3,15 +3,15 @@ pragma solidity >=0.8.0;
 
 import { UNLIMITED_DELEGATION } from "./constants.sol";
 import { IDelegationControl } from "./interfaces/IDelegationControl.sol";
-import { WorldContextProvider } from "./WorldContext.sol";
+import { SystemCall } from "./SystemCall.sol";
 
-type Delegation is address;
+type Delegation is bytes32;
 
 using DelegationInstance for Delegation global;
 
 library DelegationInstance {
   function exists(Delegation self) internal pure returns (bool) {
-    return Delegation.unwrap(self) != address(0);
+    return Delegation.unwrap(self) != bytes32("");
   }
 
   function isUnlimited(Delegation self) internal pure returns (bool) {
@@ -40,16 +40,16 @@ library DelegationInstance {
     // Early return if there is no valid delegation
     if (!exists(self)) return false;
 
-    // Call the delegation control contract to check if the delegator has granted access to the delegatee1
-    (bool success, bytes memory data) = WorldContextProvider.callWithContext({
-      target: Delegation.unwrap(self),
+    // Call the delegation control contract to check if the delegator has granted access to the delegatee
+    (bool success, bytes memory data) = SystemCall.call({
+      caller: delegatee,
+      resourceSelector: Delegation.unwrap(self),
       funcSelectorAndArgs: abi.encodeWithSelector(
         IDelegationControl.verify.selector,
         delegator,
         systemId,
         funcSelectorAndArgs
       ),
-      msgSender: delegatee,
       value: 0
     });
 
diff --git a/packages/world/src/SystemCall.sol b/packages/world/src/SystemCall.sol
new file mode 100644
index 0000000000..4f50e8813f
--- /dev/null
+++ b/packages/world/src/SystemCall.sol
@@ -0,0 +1,103 @@
+// SPDX-License-Identifier: MIT
+pragma solidity >=0.8.0;
+
+import { ResourceSelector } from "./ResourceSelector.sol";
+import { WorldContextProvider } from "./WorldContext.sol";
+import { AccessControl } from "./AccessControl.sol";
+import { ResourceSelector } from "./ResourceSelector.sol";
+import { ROOT_NAMESPACE } from "./constants.sol";
+import { WorldContextProvider } from "./WorldContext.sol";
+import { revertWithBytes } from "./utils.sol";
+
+import { IWorldErrors } from "./interfaces/IWorldErrors.sol";
+import { ISystemHook } from "./interfaces/ISystemHook.sol";
+
+import { FunctionSelectors } from "./modules/core/tables/FunctionSelectors.sol";
+import { Systems } from "./modules/core/tables/Systems.sol";
+import { SystemHooks } from "./modules/core/tables/SystemHooks.sol";
+
+library SystemCall {
+  using ResourceSelector for bytes32;
+
+  /**
+   * Call the system at the given namespace.
+   * If the system is not public, the caller must have access to the namespace or name.
+   * Returns the success status and any return data.
+   */
+  function call(
+    address caller,
+    bytes32 resourceSelector,
+    bytes memory funcSelectorAndArgs,
+    uint256 value
+  ) internal returns (bool success, bytes memory data) {
+    // Load the system data
+    (address systemAddress, bool publicAccess) = Systems.get(resourceSelector);
+
+    // Check if the system exists
+    if (systemAddress == address(0)) revert IWorldErrors.ResourceNotFound(resourceSelector.toString());
+
+    // Allow access if the system is public or the caller has access to the namespace or name
+    if (!publicAccess) AccessControl.requireAccess(resourceSelector, caller);
+
+    // Call the system and forward any return data
+    (success, data) = resourceSelector.getNamespace() == ROOT_NAMESPACE // Use delegatecall for root systems (= registered in the root namespace)
+      ? WorldContextProvider.delegatecallWithContext({
+        msgSender: caller,
+        target: systemAddress,
+        funcSelectorAndArgs: funcSelectorAndArgs
+      })
+      : WorldContextProvider.callWithContext({
+        msgSender: caller,
+        target: systemAddress,
+        funcSelectorAndArgs: funcSelectorAndArgs,
+        value: value
+      });
+  }
+
+  /**
+   * Call the system at the given namespace and call any hooks registered for it.
+   * If the system is not public, the caller must have access to the namespace or name.
+   * Returns the success status and any return data.
+   */
+  function callWithHooks(
+    address caller,
+    bytes32 resourceSelector,
+    bytes memory funcSelectorAndArgs,
+    uint256 value
+  ) internal returns (bool success, bytes memory data) {
+    // Get system hooks
+    address[] memory hooks = SystemHooks.get(resourceSelector);
+
+    // Call onBeforeCallSystem hooks (before calling the system)
+    for (uint256 i; i < hooks.length; i++) {
+      ISystemHook hook = ISystemHook(hooks[i]);
+      hook.onBeforeCallSystem(caller, resourceSelector, funcSelectorAndArgs);
+    }
+
+    // Call the system and forward any return data
+    (success, data) = call(caller, resourceSelector, funcSelectorAndArgs, value);
+
+    // Call onAfterCallSystem hooks (after calling the system)
+    for (uint256 i; i < hooks.length; i++) {
+      ISystemHook hook = ISystemHook(hooks[i]);
+      hook.onAfterCallSystem(caller, resourceSelector, funcSelectorAndArgs);
+    }
+  }
+
+  /**
+   * Call the system at the given namespace and call any hooks registered for it.
+   * If the system is not public, the caller must have access to the namespace or name.
+   * Reverts with the error if the call was not successful.
+   * Else returns any return data.
+   */
+  function callWithHooksOrRevert(
+    address caller,
+    bytes32 resourceSelector,
+    bytes memory funcSelectorAndArgs,
+    uint256 value
+  ) internal returns (bytes memory data) {
+    (bool success, bytes memory returnData) = callWithHooks(caller, resourceSelector, funcSelectorAndArgs, value);
+    if (!success) revertWithBytes(returnData);
+    return returnData;
+  }
+}
diff --git a/packages/world/src/Utils.sol b/packages/world/src/Utils.sol
index dd5a4138dc..b8f181a435 100644
--- a/packages/world/src/Utils.sol
+++ b/packages/world/src/Utils.sol
@@ -5,7 +5,7 @@ import { StoreSwitch } from "@latticexyz/store/src/StoreSwitch.sol";
 import { ResourceSelector } from "./ResourceSelector.sol";
 import { SystemRegistry } from "./Tables.sol";
 
-library Utils {
+library SystemUtils {
   /**
    * Get the namespace of this system.
    * Must be used within the context of a system (either directly, or within libraries called by a system).
@@ -22,3 +22,13 @@ library Utils {
     }
   }
 }
+
+/**
+ * Utility function to revert with raw bytes (eg. coming from a low level call or from a previously encoded error)
+ */
+function revertWithBytes(bytes memory reason) pure {
+  assembly {
+    // reason+32 is a pointer to the error message, mload(reason) is the length of the error message
+    revert(add(reason, 0x20), mload(reason))
+  }
+}
diff --git a/packages/world/src/World.sol b/packages/world/src/World.sol
index 5d46ac8538..65c62176b5 100644
--- a/packages/world/src/World.sol
+++ b/packages/world/src/World.sol
@@ -11,8 +11,10 @@ import { System } from "./System.sol";
 import { ResourceSelector } from "./ResourceSelector.sol";
 import { ROOT_NAMESPACE, ROOT_NAME } from "./constants.sol";
 import { AccessControl } from "./AccessControl.sol";
-import { Call } from "./Call.sol";
+import { SystemCall } from "./SystemCall.sol";
+import { WorldContextProvider } from "./WorldContext.sol";
 import { Delegation } from "./Delegation.sol";
+import { revertWithBytes } from "./utils.sol";
 
 import { NamespaceOwner } from "./tables/NamespaceOwner.sol";
 import { InstalledModules } from "./tables/InstalledModules.sol";
@@ -50,12 +52,10 @@ contract World is StoreRead, IStoreData, IWorldKernel {
   function installRootModule(IModule module, bytes memory args) public {
     AccessControl.requireOwnerOrSelf(ROOT_NAMESPACE, msg.sender);
 
-    Call.withSender({
+    WorldContextProvider.delegatecallWithContextOrRevert({
       msgSender: msg.sender,
       target: address(module),
-      funcSelectorAndArgs: abi.encodeWithSelector(IModule.install.selector, args),
-      delegate: true, // The module is delegate called so it can edit any table
-      value: 0
+      funcSelectorAndArgs: abi.encodeWithSelector(IModule.install.selector, args)
     });
 
     // Register the module in the InstalledModules table
@@ -179,7 +179,7 @@ contract World is StoreRead, IStoreData, IWorldKernel {
     bytes32 resourceSelector,
     bytes memory funcSelectorAndArgs
   ) external payable virtual returns (bytes memory) {
-    return Call.viaResourceSelector(msg.sender, resourceSelector, funcSelectorAndArgs, msg.value);
+    return SystemCall.callWithHooksOrRevert(msg.sender, resourceSelector, funcSelectorAndArgs, msg.value);
   }
 
   /**
@@ -196,14 +196,14 @@ contract World is StoreRead, IStoreData, IWorldKernel {
 
     if (explicitDelegation.verify(delegator, msg.sender, resourceSelector, funcSelectorAndArgs)) {
       // forward the call as `delegator`
-      return Call.viaResourceSelector(delegator, resourceSelector, funcSelectorAndArgs, msg.value);
+      return SystemCall.callWithHooksOrRevert(delegator, resourceSelector, funcSelectorAndArgs, msg.value);
     }
 
     // Check if the delegator has a fallback delegation control set
     Delegation fallbackDelegation = Delegation.wrap(Delegations.get({ delegator: delegator, delegatee: address(0) }));
     if (fallbackDelegation.verify(delegator, msg.sender, resourceSelector, funcSelectorAndArgs)) {
       // forward the call with `from` as `msgSender`
-      return Call.viaResourceSelector(delegator, resourceSelector, funcSelectorAndArgs, msg.value);
+      return SystemCall.callWithHooksOrRevert(delegator, resourceSelector, funcSelectorAndArgs, msg.value);
     }
 
     revert DelegationNotFound(delegator, msg.sender);
@@ -231,8 +231,18 @@ contract World is StoreRead, IStoreData, IWorldKernel {
     // Replace function selector in the calldata with the system function selector
     bytes memory callData = Bytes.setBytes4(msg.data, 0, systemFunctionSelector);
 
-    // Call the function and forward the calldata and returndata
-    bytes memory returnData = Call.viaResourceSelector(msg.sender, resourceSelector, callData, msg.value);
+    // Call the function and forward the call data
+    (bool success, bytes memory returnData) = SystemCall.callWithHooks(
+      msg.sender,
+      resourceSelector,
+      callData,
+      msg.value
+    );
+
+    // If the call was not successful, revert with the return data
+    if (!success) revertWithBytes(returnData);
+
+    // If the call was successful, return the return data
     assembly {
       return(add(returnData, 0x20), mload(returnData))
     }
diff --git a/packages/world/src/WorldContext.sol b/packages/world/src/WorldContext.sol
index 8437a766fb..2e79efdc8f 100644
--- a/packages/world/src/WorldContext.sol
+++ b/packages/world/src/WorldContext.sol
@@ -2,6 +2,7 @@
 pragma solidity >=0.8.0;
 
 import { StoreSwitch } from "@latticexyz/store/src/StoreSwitch.sol";
+import { revertWithBytes } from "./utils.sol";
 
 // Similar to https://eips.ethereum.org/EIPS/eip-2771, but any contract can be the trusted forwarder.
 // This should only be used for contracts without own storage, like Systems.
@@ -44,4 +45,25 @@ library WorldContextProvider {
   ) internal returns (bool success, bytes memory data) {
     (success, data) = target.delegatecall(appendContext(funcSelectorAndArgs, msgSender));
   }
+
+  function callWithContextOrRevert(
+    address target,
+    bytes memory funcSelectorAndArgs,
+    address msgSender,
+    uint256 value
+  ) internal returns (bytes memory data) {
+    (bool success, bytes memory _data) = callWithContext(target, funcSelectorAndArgs, msgSender, value);
+    if (!success) revertWithBytes(_data);
+    return _data;
+  }
+
+  function delegatecallWithContextOrRevert(
+    address target,
+    bytes memory funcSelectorAndArgs,
+    address msgSender
+  ) internal returns (bytes memory data) {
+    (bool success, bytes memory _data) = delegatecallWithContext(target, funcSelectorAndArgs, msgSender);
+    if (!success) revertWithBytes(_data);
+    return _data;
+  }
 }
diff --git a/packages/world/src/constants.sol b/packages/world/src/constants.sol
index a2cc7177d1..a4a2538803 100644
--- a/packages/world/src/constants.sol
+++ b/packages/world/src/constants.sol
@@ -3,4 +3,4 @@ pragma solidity >=0.8.0;
 
 bytes16 constant ROOT_NAMESPACE = 0;
 bytes16 constant ROOT_NAME = 0;
-address constant UNLIMITED_DELEGATION = address(1);
+bytes32 constant UNLIMITED_DELEGATION = bytes32(abi.encodePacked(ROOT_NAMESPACE, bytes16("unlimited.d")));
diff --git a/packages/world/src/interfaces/ISystemHook.sol b/packages/world/src/interfaces/ISystemHook.sol
index 6d7b1b8147..3810f571a6 100644
--- a/packages/world/src/interfaces/ISystemHook.sol
+++ b/packages/world/src/interfaces/ISystemHook.sol
@@ -2,7 +2,7 @@
 pragma solidity >=0.8.0;
 
 interface ISystemHook {
-  function onBeforeCallSystem(address msgSender, address systemAddress, bytes memory funcSelectorAndArgs) external;
+  function onBeforeCallSystem(address msgSender, bytes32 resourceSelector, bytes memory funcSelectorAndArgs) external;
 
-  function onAfterCallSystem(address msgSender, address systemAddress, bytes memory funcSelectorAndArgs) external;
+  function onAfterCallSystem(address msgSender, bytes32 resourceSelector, bytes memory funcSelectorAndArgs) external;
 }
diff --git a/packages/world/src/interfaces/IWorldRegistrationSystem.sol b/packages/world/src/interfaces/IWorldRegistrationSystem.sol
index 9f6ddf01cb..d4479d1ba1 100644
--- a/packages/world/src/interfaces/IWorldRegistrationSystem.sol
+++ b/packages/world/src/interfaces/IWorldRegistrationSystem.sol
@@ -27,7 +27,7 @@ interface IWorldRegistrationSystem {
 
   function registerDelegation(
     address delegatee,
-    address delegationControl,
+    bytes32 delegationControl,
     bytes memory initFuncSelectorAndArgs
   ) external;
 }
diff --git a/packages/world/src/modules/core/CoreModule.sol b/packages/world/src/modules/core/CoreModule.sol
index 7919f956d5..99d2509f04 100644
--- a/packages/world/src/modules/core/CoreModule.sol
+++ b/packages/world/src/modules/core/CoreModule.sol
@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: MIT
 pragma solidity >=0.8.0;
 
-import { Call } from "../../Call.sol";
+import { WorldContextProvider } from "../../WorldContext.sol";
 import { ROOT_NAMESPACE } from "../../constants.sol";
 import { WorldContextConsumer } from "../../WorldContext.sol";
 import { Resource } from "../../Types.sol";
@@ -74,11 +74,9 @@ contract CoreModule is IModule, WorldContextConsumer {
    */
   function _registerCoreSystem() internal {
     // Use the CoreSystem's `registerSystem` implementation to register itself on the World.
-    Call.withSender({
+    WorldContextProvider.delegatecallWithContextOrRevert({
       msgSender: _msgSender(),
       target: coreSystem,
-      delegate: true,
-      value: 0,
       funcSelectorAndArgs: abi.encodeWithSelector(
         WorldRegistrationSystem.registerSystem.selector,
         ResourceSelector.from(ROOT_NAMESPACE, CORE_SYSTEM_NAME),
@@ -115,11 +113,9 @@ contract CoreModule is IModule, WorldContextConsumer {
     for (uint256 i = 0; i < functionSelectors.length; i++) {
       // Use the CoreSystem's `registerRootFunctionSelector` to register the
       // root function selectors in the World.
-      Call.withSender({
+      WorldContextProvider.delegatecallWithContextOrRevert({
         msgSender: _msgSender(),
         target: coreSystem,
-        delegate: true,
-        value: 0,
         funcSelectorAndArgs: abi.encodeWithSelector(
           WorldRegistrationSystem.registerRootFunctionSelector.selector,
           ResourceSelector.from(ROOT_NAMESPACE, CORE_SYSTEM_NAME),
diff --git a/packages/world/src/modules/core/implementations/AccessManagementSystem.sol b/packages/world/src/modules/core/implementations/AccessManagementSystem.sol
index df10f158e0..3fd2c695d8 100644
--- a/packages/world/src/modules/core/implementations/AccessManagementSystem.sol
+++ b/packages/world/src/modules/core/implementations/AccessManagementSystem.sol
@@ -5,7 +5,6 @@ import { IModule } from "../../../interfaces/IModule.sol";
 import { System } from "../../../System.sol";
 import { AccessControl } from "../../../AccessControl.sol";
 import { ResourceSelector } from "../../../ResourceSelector.sol";
-import { Call } from "../../../Call.sol";
 import { ResourceAccess } from "../../../tables/ResourceAccess.sol";
 import { InstalledModules } from "../../../tables/InstalledModules.sol";
 
diff --git a/packages/world/src/modules/core/implementations/EphemeralRecordSystem.sol b/packages/world/src/modules/core/implementations/EphemeralRecordSystem.sol
index f49bb8996b..d52278520c 100644
--- a/packages/world/src/modules/core/implementations/EphemeralRecordSystem.sol
+++ b/packages/world/src/modules/core/implementations/EphemeralRecordSystem.sol
@@ -3,13 +3,9 @@ pragma solidity >=0.8.0;
 
 import { IStoreEphemeral } from "@latticexyz/store/src/IStore.sol";
 import { Schema } from "@latticexyz/store/src/Schema.sol";
-import { IModule } from "../../../interfaces/IModule.sol";
 import { System } from "../../../System.sol";
 import { ResourceSelector } from "../../../ResourceSelector.sol";
 import { AccessControl } from "../../../AccessControl.sol";
-import { Call } from "../../../Call.sol";
-import { ResourceAccess } from "../../../tables/ResourceAccess.sol";
-import { InstalledModules } from "../../../tables/InstalledModules.sol";
 import { StoreCore } from "@latticexyz/store/src/StoreCore.sol";
 
 contract EphemeralRecordSystem is IStoreEphemeral, System {
diff --git a/packages/world/src/modules/core/implementations/ModuleInstallationSystem.sol b/packages/world/src/modules/core/implementations/ModuleInstallationSystem.sol
index 8639ece1a5..2e55da8b57 100644
--- a/packages/world/src/modules/core/implementations/ModuleInstallationSystem.sol
+++ b/packages/world/src/modules/core/implementations/ModuleInstallationSystem.sol
@@ -4,7 +4,7 @@ pragma solidity >=0.8.0;
 import { IModule } from "../../../interfaces/IModule.sol";
 import { System } from "../../../System.sol";
 import { AccessControl } from "../../../AccessControl.sol";
-import { Call } from "../../../Call.sol";
+import { WorldContextProvider } from "../../../WorldContext.sol";
 import { ResourceAccess } from "../../../tables/ResourceAccess.sol";
 import { InstalledModules } from "../../../tables/InstalledModules.sol";
 
@@ -16,11 +16,10 @@ contract ModuleInstallationSystem is System {
    * Install the given module at the given namespace in the World.
    */
   function installModule(IModule module, bytes memory args) public {
-    Call.withSender({
+    WorldContextProvider.callWithContextOrRevert({
       msgSender: _msgSender(),
       target: address(module),
       funcSelectorAndArgs: abi.encodeWithSelector(IModule.install.selector, args),
-      delegate: false,
       value: 0
     });
 
diff --git a/packages/world/src/modules/core/implementations/StoreRegistrationSystem.sol b/packages/world/src/modules/core/implementations/StoreRegistrationSystem.sol
index 7486549f6a..c832ace089 100644
--- a/packages/world/src/modules/core/implementations/StoreRegistrationSystem.sol
+++ b/packages/world/src/modules/core/implementations/StoreRegistrationSystem.sol
@@ -10,7 +10,7 @@ import { ResourceSelector } from "../../../ResourceSelector.sol";
 import { Resource } from "../../../Types.sol";
 import { ROOT_NAMESPACE, ROOT_NAME } from "../../../constants.sol";
 import { AccessControl } from "../../../AccessControl.sol";
-import { Call } from "../../../Call.sol";
+import { WorldContextProvider } from "../../../WorldContext.sol";
 import { NamespaceOwner } from "../../../tables/NamespaceOwner.sol";
 import { ResourceAccess } from "../../../tables/ResourceAccess.sol";
 import { ISystemHook } from "../../../interfaces/ISystemHook.sol";
@@ -51,12 +51,10 @@ contract StoreRegistrationSystem is System, IWorldErrors {
       // We can't call IBaseWorld(this).registerSchema directly because it would be handled like
       // an external call, so msg.sender would be the address of the World contract
       (address systemAddress, ) = Systems.get(ResourceSelector.from(ROOT_NAMESPACE, CORE_SYSTEM_NAME));
-      Call.withSender({
+      WorldContextProvider.delegatecallWithContextOrRevert({
         msgSender: _msgSender(),
         target: systemAddress,
-        funcSelectorAndArgs: abi.encodeWithSelector(WorldRegistrationSystem.registerNamespace.selector, namespace),
-        delegate: true,
-        value: 0
+        funcSelectorAndArgs: abi.encodeWithSelector(WorldRegistrationSystem.registerNamespace.selector, namespace)
       });
     } else {
       // otherwise require caller to own the namespace
diff --git a/packages/world/src/modules/core/implementations/WorldRegistrationSystem.sol b/packages/world/src/modules/core/implementations/WorldRegistrationSystem.sol
index 9f65fd34b1..97c3c415d1 100644
--- a/packages/world/src/modules/core/implementations/WorldRegistrationSystem.sol
+++ b/packages/world/src/modules/core/implementations/WorldRegistrationSystem.sol
@@ -5,7 +5,7 @@ import { System } from "../../../System.sol";
 import { WorldContextConsumer } from "../../../WorldContext.sol";
 import { ResourceSelector } from "../../../ResourceSelector.sol";
 import { Resource } from "../../../Types.sol";
-import { WorldContextProvider } from "../../../WorldContext.sol";
+import { SystemCall } from "../../../SystemCall.sol";
 import { ROOT_NAMESPACE, ROOT_NAME, UNLIMITED_DELEGATION } from "../../../constants.sol";
 import { AccessControl } from "../../../AccessControl.sol";
 import { NamespaceOwner } from "../../../tables/NamespaceOwner.sol";
@@ -159,7 +159,7 @@ contract WorldRegistrationSystem is System, IWorldErrors {
    */
   function registerDelegation(
     address delegatee,
-    address delegationControl,
+    bytes32 delegationControl,
     bytes memory initFuncSelectorAndArgs
   ) public {
     // Store the delegation control contract address
@@ -167,10 +167,10 @@ contract WorldRegistrationSystem is System, IWorldErrors {
 
     // If the delegation is not unlimited, call the delegation control contract's init function
     if (delegationControl != UNLIMITED_DELEGATION && initFuncSelectorAndArgs.length > 0) {
-      WorldContextProvider.callWithContext({
-        target: address(delegationControl),
+      SystemCall.call({
+        caller: _msgSender(),
+        resourceSelector: delegationControl,
         funcSelectorAndArgs: initFuncSelectorAndArgs,
-        msgSender: _msgSender(),
         value: 0
       });
     }
diff --git a/packages/world/src/modules/delegations/DelegationsModule.sol b/packages/world/src/modules/delegations/DelegationsModule.sol
index b61ec1ade2..3215638889 100644
--- a/packages/world/src/modules/delegations/DelegationsModule.sol
+++ b/packages/world/src/modules/delegations/DelegationsModule.sol
@@ -10,7 +10,7 @@ import { ResourceSelector } from "../../ResourceSelector.sol";
 import { DisposableDelegations } from "./tables/DisposableDelegations.sol";
 import { DisposableDelegationControl } from "./DisposableDelegationControl.sol";
 
-import { MODULE_NAME, NAMESPACE, DISPOSABLE_DELEGATION, DISPOSABLE_DELEGATION_TABLE } from "./constants.sol";
+import { MODULE_NAME, NAMESPACE, DISPOSABLE_DELEGATION, DISPOSABLE_DELEGATION_ROOT, DISPOSABLE_DELEGATION_TABLE, DISPOSABLE_DELEGATION_TABLE_ROOT } from "./constants.sol";
 
 /**
  * This module registers tables and delegation control systems required for standard delegations
@@ -25,10 +25,13 @@ contract DelegationsModule is IModule, WorldContextConsumer {
   function install(bytes memory) public {
     IBaseWorld world = IBaseWorld(_world());
 
-    // Register table
-    DisposableDelegations.register(world, DISPOSABLE_DELEGATION_TABLE);
-
-    // Register delegation control system
-    world.registerSystem(DISPOSABLE_DELEGATION, disposableDelegationControl, true);
+    // If this module is installed as a root module, register it in the root namespace
+    if (address(world) == address(this)) {
+      DisposableDelegations.register(world, DISPOSABLE_DELEGATION_TABLE_ROOT);
+      world.registerSystem(DISPOSABLE_DELEGATION_ROOT, disposableDelegationControl, true);
+    } else {
+      DisposableDelegations.register(world, DISPOSABLE_DELEGATION_TABLE);
+      world.registerSystem(DISPOSABLE_DELEGATION, disposableDelegationControl, true);
+    }
   }
 }
diff --git a/packages/world/src/modules/delegations/constants.sol b/packages/world/src/modules/delegations/constants.sol
index 8bbb3ed4d8..94eb147800 100644
--- a/packages/world/src/modules/delegations/constants.sol
+++ b/packages/world/src/modules/delegations/constants.sol
@@ -1,10 +1,11 @@
 // SPDX-License-Identifier: MIT
 pragma solidity >=0.8.0;
 import { ResourceSelector } from "../../ResourceSelector.sol";
+import { ROOT_NAMESPACE } from "../../constants.sol";
 
-bytes16 constant NAMESPACE = bytes16("delegations");
 bytes16 constant MODULE_NAME = bytes16("delegations.m");
+bytes16 constant NAMESPACE = bytes16("delegations");
 bytes32 constant DISPOSABLE_DELEGATION = bytes32(abi.encodePacked(NAMESPACE, bytes16("disposable.d")));
-
-// TODO: once the config supports multiple namespaces we don't need to manually define this id but can import it from the table library
+bytes32 constant DISPOSABLE_DELEGATION_ROOT = bytes32(abi.encodePacked(ROOT_NAMESPACE, bytes16("disposable.d")));
 bytes32 constant DISPOSABLE_DELEGATION_TABLE = bytes32(abi.encodePacked(NAMESPACE, bytes16("disposable.t")));
+bytes32 constant DISPOSABLE_DELEGATION_TABLE_ROOT = bytes32(abi.encodePacked(ROOT_NAMESPACE, bytes16("disposable.t")));
diff --git a/packages/world/src/tables/Delegations.sol b/packages/world/src/tables/Delegations.sol
index ca14df6747..1a444ff748 100644
--- a/packages/world/src/tables/Delegations.sol
+++ b/packages/world/src/tables/Delegations.sol
@@ -33,7 +33,7 @@ library Delegations {
   /** Get the table's value schema */
   function getValueSchema() internal pure returns (Schema) {
     SchemaType[] memory _schema = new SchemaType[](1);
-    _schema[0] = SchemaType.ADDRESS;
+    _schema[0] = SchemaType.BYTES32;
 
     return SchemaLib.encode(_schema);
   }
@@ -62,27 +62,27 @@ library Delegations {
   }
 
   /** Get delegationControl */
-  function get(address delegator, address delegatee) internal view returns (address delegationControl) {
+  function get(address delegator, address delegatee) internal view returns (bytes32 delegationControl) {
     bytes32[] memory _keyTuple = new bytes32[](2);
     _keyTuple[0] = bytes32(uint256(uint160(delegator)));
     _keyTuple[1] = bytes32(uint256(uint160(delegatee)));
 
     bytes memory _blob = StoreSwitch.getField(_tableId, _keyTuple, 0, getValueSchema());
-    return (address(Bytes.slice20(_blob, 0)));
+    return (Bytes.slice32(_blob, 0));
   }
 
   /** Get delegationControl (using the specified store) */
-  function get(IStore _store, address delegator, address delegatee) internal view returns (address delegationControl) {
+  function get(IStore _store, address delegator, address delegatee) internal view returns (bytes32 delegationControl) {
     bytes32[] memory _keyTuple = new bytes32[](2);
     _keyTuple[0] = bytes32(uint256(uint160(delegator)));
     _keyTuple[1] = bytes32(uint256(uint160(delegatee)));
 
     bytes memory _blob = _store.getField(_tableId, _keyTuple, 0, getValueSchema());
-    return (address(Bytes.slice20(_blob, 0)));
+    return (Bytes.slice32(_blob, 0));
   }
 
   /** Set delegationControl */
-  function set(address delegator, address delegatee, address delegationControl) internal {
+  function set(address delegator, address delegatee, bytes32 delegationControl) internal {
     bytes32[] memory _keyTuple = new bytes32[](2);
     _keyTuple[0] = bytes32(uint256(uint160(delegator)));
     _keyTuple[1] = bytes32(uint256(uint160(delegatee)));
@@ -91,7 +91,7 @@ library Delegations {
   }
 
   /** Set delegationControl (using the specified store) */
-  function set(IStore _store, address delegator, address delegatee, address delegationControl) internal {
+  function set(IStore _store, address delegator, address delegatee, bytes32 delegationControl) internal {
     bytes32[] memory _keyTuple = new bytes32[](2);
     _keyTuple[0] = bytes32(uint256(uint160(delegator)));
     _keyTuple[1] = bytes32(uint256(uint160(delegatee)));
@@ -100,7 +100,7 @@ library Delegations {
   }
 
   /** Tightly pack full data using this table's schema */
-  function encode(address delegationControl) internal pure returns (bytes memory) {
+  function encode(bytes32 delegationControl) internal pure returns (bytes memory) {
     return abi.encodePacked(delegationControl);
   }
 
diff --git a/packages/world/test/DelegationsModule.t.sol b/packages/world/test/DelegationsModule.t.sol
index 04e54db302..47382af0fa 100644
--- a/packages/world/test/DelegationsModule.t.sol
+++ b/packages/world/test/DelegationsModule.t.sol
@@ -12,7 +12,7 @@ import { CoreModule } from "../src/modules/core/CoreModule.sol";
 import { Systems } from "../src/modules/core/tables/Systems.sol";
 import { DelegationsModule } from "../src/modules/delegations/DelegationsModule.sol";
 import { DisposableDelegationControl } from "../src/modules/delegations/DisposableDelegationControl.sol";
-import { DISPOSABLE_DELEGATION } from "../src/modules/delegations/DelegationsModule.sol";
+import { DISPOSABLE_DELEGATION, DISPOSABLE_DELEGATION_ROOT } from "../src/modules/delegations/DelegationsModule.sol";
 
 import { WorldTestSystem } from "./World.t.sol";
 
@@ -25,24 +25,62 @@ contract DelegationsModuleTest is Test, GasReporter {
   function setUp() public {
     world = IBaseWorld(address(new World()));
     world.installRootModule(new CoreModule(), new bytes(0));
-    world.installModule(new DelegationsModule(), new bytes(0));
 
     // Register a new system
     WorldTestSystem system = new WorldTestSystem();
     world.registerSystem(systemResourceSelector, system, true);
   }
 
+  function testCallFromDisposableDelegationRoot() public {
+    // Install Delegations module as root module
+    world.installRootModule(new DelegationsModule(), new bytes(0));
+
+    // Register the disposable delegation for one call to the system's msgSender function
+    vm.prank(delegator);
+    startGasReport("register a disposable delegation with a root module");
+    world.registerDelegation(
+      delegatee,
+      DISPOSABLE_DELEGATION_ROOT,
+      abi.encodeWithSelector(
+        DisposableDelegationControl.initDelegation.selector,
+        delegatee,
+        systemResourceSelector,
+        abi.encodeWithSelector(WorldTestSystem.msgSender.selector),
+        1
+      )
+    );
+    endGasReport();
+
+    // Call a system from the delegatee on behalf of the delegator
+    vm.prank(delegatee);
+    startGasReport("call a system via a disposable delegation with a root module");
+    bytes memory returnData = world.callFrom(
+      delegator,
+      systemResourceSelector,
+      abi.encodeWithSelector(WorldTestSystem.msgSender.selector)
+    );
+    endGasReport();
+    address returnedAddress = abi.decode(returnData, (address));
+
+    // Expect the system to have received the delegator's address
+    assertEq(returnedAddress, delegator);
+
+    // Expect the delegation to have been used up
+    vm.expectRevert(abi.encodeWithSelector(IWorldErrors.DelegationNotFound.selector, delegator, delegatee));
+    vm.prank(delegatee);
+    world.callFrom(delegator, systemResourceSelector, abi.encodeWithSelector(WorldTestSystem.msgSender.selector));
+  }
+
   function testCallFromDisposableDelegation() public {
-    // Get the address for the disposable delegation
-    // TODO: make it easier to register a delegation if the delegation control system's address is not known
-    (address disposableDelegation, ) = Systems.get(world, DISPOSABLE_DELEGATION);
+    // Install Delegations module as root module
+    world.installModule(new DelegationsModule(), new bytes(0));
 
     // Register the disposable delegation for one call to the system's msgSender function
     vm.prank(delegator);
-    startGasReport("register a disposable delegation");
+    startGasReport("register a disposable delegation with a non-root module");
     world.registerDelegation(
       delegatee,
-      disposableDelegation,
+      DISPOSABLE_DELEGATION,
       abi.encodeWithSelector(
         DisposableDelegationControl.initDelegation.selector,
         delegatee,
@@ -55,7 +93,7 @@ contract DelegationsModuleTest is Test, GasReporter {
 
     // Call a system from the delegatee on behalf of the delegator
     vm.prank(delegatee);
-    startGasReport("call a system via a disposable delegation");
+    startGasReport("call a system via a disposable delegation with a non-root module");
     bytes memory returnData = world.callFrom(
       delegator,
       systemResourceSelector,
diff --git a/packages/world/test/Utils.t.sol b/packages/world/test/Utils.t.sol
index 55d066d32c..7affddff18 100644
--- a/packages/world/test/Utils.t.sol
+++ b/packages/world/test/Utils.t.sol
@@ -3,7 +3,7 @@ pragma solidity >=0.8.0;
 
 import { Test } from "forge-std/Test.sol";
 
-import { Utils } from "../src/Utils.sol";
+import { SystemUtils, revertWithBytes } from "../src/utils.sol";
 import { System } from "../src/System.sol";
 import { World } from "../src/World.sol";
 import { IBaseWorld } from "../src/interfaces/IBaseWorld.sol";
@@ -13,7 +13,7 @@ import { CoreModule } from "../src/modules/core/CoreModule.sol";
 
 contract UtilsTestSystem is System {
   function systemNamespace() public view returns (bytes16) {
-    return Utils.systemNamespace();
+    return SystemUtils.systemNamespace();
   }
 }
 
@@ -21,6 +21,8 @@ contract UtilsTest is Test {
   using ResourceSelector for bytes32;
   IBaseWorld internal world;
 
+  error SomeError(uint256 someValue, string someString);
+
   function setUp() public {
     world = IBaseWorld(address(new World()));
     world.installRootModule(new CoreModule(), new bytes(0));
@@ -54,4 +56,12 @@ contract UtilsTest is Test {
     returnedNamespace = _registerAndGetNamespace(namespace);
     assertEq(returnedNamespace, namespace);
   }
+
+  function testRevertWithBytes() public {
+    vm.expectRevert(abi.encodeWithSelector(SomeError.selector, 1, "test"));
+    revert SomeError(1, "test");
+
+    vm.expectRevert(abi.encodeWithSelector(SomeError.selector, 1, "test"));
+    revertWithBytes(abi.encodeWithSelector(SomeError.selector, 1, "test"));
+  }
 }
diff --git a/packages/world/test/World.t.sol b/packages/world/test/World.t.sol
index 48b7749bed..58ba3aeef1 100644
--- a/packages/world/test/World.t.sol
+++ b/packages/world/test/World.t.sol
@@ -141,12 +141,12 @@ contract WorldTestTableHook is IStoreHook {
 contract WorldTestSystemHook is ISystemHook {
   event SystemHookCalled(bytes data);
 
-  function onBeforeCallSystem(address msgSender, address systemAddress, bytes memory funcSelectorAndArgs) public {
-    emit SystemHookCalled(abi.encode("before", msgSender, systemAddress, funcSelectorAndArgs));
+  function onBeforeCallSystem(address msgSender, bytes32 resourceSelector, bytes memory funcSelectorAndArgs) public {
+    emit SystemHookCalled(abi.encode("before", msgSender, resourceSelector, funcSelectorAndArgs));
   }
 
-  function onAfterCallSystem(address msgSender, address systemAddress, bytes memory funcSelectorAndArgs) public {
-    emit SystemHookCalled(abi.encode("after", msgSender, systemAddress, funcSelectorAndArgs));
+  function onAfterCallSystem(address msgSender, bytes32 resourceSelector, bytes memory funcSelectorAndArgs) public {
+    emit SystemHookCalled(abi.encode("after", msgSender, resourceSelector, funcSelectorAndArgs));
   }
 }
 
@@ -664,30 +664,30 @@ contract WorldTest is Test, GasReporter {
   }
 
   function testRegisterSystemHook() public {
-    bytes32 tableId = ResourceSelector.from("namespace", "testTable");
+    bytes32 systemId = ResourceSelector.from("namespace", "testTable");
 
     // Register a new system
     WorldTestSystem system = new WorldTestSystem();
-    world.registerSystem(tableId, system, false);
+    world.registerSystem(systemId, system, false);
 
     // Register a new hook
     ISystemHook systemHook = new WorldTestSystemHook();
-    world.registerSystemHook(tableId, systemHook);
+    world.registerSystemHook(systemId, systemHook);
 
     bytes memory funcSelectorAndArgs = abi.encodeWithSelector(bytes4(keccak256("fallbackselector")));
 
     // Expect the hooks to be called in correct order
     vm.expectEmit(true, true, true, true);
-    emit SystemHookCalled(abi.encode("before", address(this), address(system), funcSelectorAndArgs));
+    emit SystemHookCalled(abi.encode("before", address(this), systemId, funcSelectorAndArgs));
 
     vm.expectEmit(true, true, true, true);
     emit WorldTestSystemLog("fallback");
 
     vm.expectEmit(true, true, true, true);
-    emit SystemHookCalled(abi.encode("after", address(this), address(system), funcSelectorAndArgs));
+    emit SystemHookCalled(abi.encode("after", address(this), systemId, funcSelectorAndArgs));
 
     // Call a system fallback function without arguments via the World
-    world.call(tableId, funcSelectorAndArgs);
+    world.call(systemId, funcSelectorAndArgs);
   }
 
   function testWriteRootSystem() public {