diff --git a/lib/actions/user-actions.js b/lib/actions/user-actions.js
--- a/lib/actions/user-actions.js
+++ b/lib/actions/user-actions.js
@@ -32,12 +32,16 @@
   SubscriptionUpdateResult,
 } from '../types/subscription-types.js';
 import type { UserInfo, PasswordUpdate } from '../types/user-types.js';
+import { extractKeyserverIDFromID } from '../utils/action-utils.js';
 import type {
   CallServerEndpoint,
   CallServerEndpointOptions,
 } from '../utils/call-server-endpoint.js';
 import { getConfig } from '../utils/config.js';
+import type { CallKeyserverEndpoint } from '../utils/keyserver-call';
+import { useKeyserverCall } from '../utils/keyserver-call.js';
 import sleep from '../utils/sleep.js';
+import { ashoatKeyserverID } from '../utils/validation-utils.js';
 
 const logOutActionTypes = Object.freeze({
   started: 'LOG_OUT_STARTED',
@@ -71,17 +75,24 @@
 const claimUsernameCallServerEndpointOptions = { timeout: 500 };
 const claimUsername =
   (
-    callServerEndpoint: CallServerEndpoint,
+    callKeyserverEndpoint: CallKeyserverEndpoint,
   ): (() => Promise<ClaimUsernameResponse>) =>
   async () => {
-    const response = await callServerEndpoint(
-      'claim_username',
-      {},
-      { ...claimUsernameCallServerEndpointOptions },
-    );
-    return response;
+    const requests = { [ashoatKeyserverID]: {} };
+    const responses = await callKeyserverEndpoint('claim_username', requests, {
+      ...claimUsernameCallServerEndpointOptions,
+    });
+    const response = responses[ashoatKeyserverID];
+    return {
+      message: response.message,
+      signature: response.signature,
+    };
   };
 
+function useClaimUsername(): () => Promise<ClaimUsernameResponse> {
+  return useKeyserverCall(claimUsername);
+}
+
 const deleteAccountActionTypes = Object.freeze({
   started: 'DELETE_ACCOUNT_STARTED',
   success: 'DELETE_ACCOUNT_SUCCESS',
@@ -248,21 +259,31 @@
 });
 const updateSubscription =
   (
-    callServerEndpoint: CallServerEndpoint,
+    callKeyserverEndpoint: CallKeyserverEndpoint,
   ): ((
-    subscriptionUpdate: SubscriptionUpdateRequest,
+    input: SubscriptionUpdateRequest,
   ) => Promise<SubscriptionUpdateResult>) =>
-  async subscriptionUpdate => {
-    const response = await callServerEndpoint(
+  async input => {
+    const keyserverID = extractKeyserverIDFromID(input.threadID);
+    const requests = { [keyserverID]: input };
+
+    const responses = await callKeyserverEndpoint(
       'update_user_subscription',
-      subscriptionUpdate,
+      requests,
     );
+    const response = responses[keyserverID];
     return {
-      threadID: subscriptionUpdate.threadID,
+      threadID: input.threadID,
       subscription: response.threadSubscription,
     };
   };
 
+function useUpdateSubscription(): (
+  input: SubscriptionUpdateRequest,
+) => Promise<SubscriptionUpdateResult> {
+  return useKeyserverCall(updateSubscription);
+}
+
 const setUserSettingsActionTypes = Object.freeze({
   started: 'SET_USER_SETTINGS_STARTED',
   success: 'SET_USER_SETTINGS_SUCCESS',
@@ -271,12 +292,23 @@
 
 const setUserSettings =
   (
-    callServerEndpoint: CallServerEndpoint,
-  ): ((userSettingsRequest: UpdateUserSettingsRequest) => Promise<void>) =>
-  async userSettingsRequest => {
-    await callServerEndpoint('update_user_settings', userSettingsRequest);
+    callKeyserverEndpoint: CallKeyserverEndpoint,
+    allKeyserverIDs: $ReadOnlyArray<string>,
+  ): ((input: UpdateUserSettingsRequest) => Promise<void>) =>
+  async input => {
+    const requests = {};
+    for (const keyserverID of allKeyserverIDs) {
+      requests[keyserverID] = input;
+    }
+    await callKeyserverEndpoint('update_user_settings', requests);
   };
 
+function useSetUserSettings(): (
+  input: UpdateUserSettingsRequest,
+) => Promise<void> {
+  return useKeyserverCall(setUserSettings);
+}
+
 const getSessionPublicKeys =
   (
     callServerEndpoint: CallServerEndpoint,
@@ -345,7 +377,7 @@
   changeUserPasswordActionTypes,
   changeUserPassword,
   claimUsernameActionTypes,
-  claimUsername,
+  useClaimUsername,
   deleteAccount,
   deleteAccountActionTypes,
   getSessionPublicKeys,
@@ -362,9 +394,9 @@
   searchUsersActionTypes,
   exactSearchUser,
   exactSearchUserActionTypes,
-  setUserSettings,
+  useSetUserSettings,
   setUserSettingsActionTypes,
-  updateSubscription,
+  useUpdateSubscription,
   updateSubscriptionActionTypes,
   policyAcknowledgment,
   policyAcknowledgmentActionTypes,
diff --git a/native/chat/settings/thread-settings-home-notifs.react.js b/native/chat/settings/thread-settings-home-notifs.react.js
--- a/native/chat/settings/thread-settings-home-notifs.react.js
+++ b/native/chat/settings/thread-settings-home-notifs.react.js
@@ -5,7 +5,7 @@
 
 import {
   updateSubscriptionActionTypes,
-  updateSubscription,
+  useUpdateSubscription,
 } from 'lib/actions/user-actions.js';
 import type {
   SubscriptionUpdateRequest,
@@ -13,10 +13,7 @@
 } from 'lib/types/subscription-types.js';
 import { type ThreadInfo } from 'lib/types/thread-types.js';
 import type { DispatchActionPromise } from 'lib/utils/action-utils.js';
-import {
-  useServerCall,
-  useDispatchActionPromise,
-} from 'lib/utils/action-utils.js';
+import { useDispatchActionPromise } from 'lib/utils/action-utils.js';
 
 import SingleLine from '../../components/single-line.react.js';
 import { useStyles } from '../../themes/colors.js';
@@ -105,7 +102,7 @@
   ) {
     const styles = useStyles(unboundStyles);
     const dispatchActionPromise = useDispatchActionPromise();
-    const callUpdateSubscription = useServerCall(updateSubscription);
+    const callUpdateSubscription = useUpdateSubscription();
     return (
       <ThreadSettingsHomeNotifs
         {...props}
diff --git a/native/chat/settings/thread-settings-push-notifs.react.js b/native/chat/settings/thread-settings-push-notifs.react.js
--- a/native/chat/settings/thread-settings-push-notifs.react.js
+++ b/native/chat/settings/thread-settings-push-notifs.react.js
@@ -6,7 +6,7 @@
 
 import {
   updateSubscriptionActionTypes,
-  updateSubscription,
+  useUpdateSubscription,
 } from 'lib/actions/user-actions.js';
 import type {
   SubscriptionUpdateRequest,
@@ -14,10 +14,7 @@
 } from 'lib/types/subscription-types.js';
 import { type ThreadInfo } from 'lib/types/thread-types.js';
 import type { DispatchActionPromise } from 'lib/utils/action-utils.js';
-import {
-  useServerCall,
-  useDispatchActionPromise,
-} from 'lib/utils/action-utils.js';
+import { useDispatchActionPromise } from 'lib/utils/action-utils.js';
 
 import SingleLine from '../../components/single-line.react.js';
 import SWMansionIcon from '../../components/swmansion-icon.react.js';
@@ -176,7 +173,7 @@
   ) {
     const styles = useStyles(unboundStyles);
     const dispatchActionPromise = useDispatchActionPromise();
-    const callUpdateSubscription = useServerCall(updateSubscription);
+    const callUpdateSubscription = useUpdateSubscription();
     const hasPushPermissions = useSelector(
       state => state.deviceToken !== null && state.deviceToken !== undefined,
     );
diff --git a/native/profile/default-notifications-preferences.react.js b/native/profile/default-notifications-preferences.react.js
--- a/native/profile/default-notifications-preferences.react.js
+++ b/native/profile/default-notifications-preferences.react.js
@@ -5,7 +5,7 @@
 import { ScrollView } from 'react-native-gesture-handler';
 
 import {
-  setUserSettings,
+  useSetUserSettings,
   setUserSettingsActionTypes,
 } from 'lib/actions/user-actions.js';
 import { registerFetchKey } from 'lib/reducers/loading-reducer.js';
@@ -18,7 +18,6 @@
 } from 'lib/types/account-types.js';
 import {
   type DispatchActionPromise,
-  useServerCall,
   useDispatchActionPromise,
 } from 'lib/utils/action-utils.js';
 
@@ -185,7 +184,7 @@
   ) {
     const styles = useStyles(unboundStyles);
     const dispatchActionPromise = useDispatchActionPromise();
-    const changeNotificationSettings = useServerCall(setUserSettings);
+    const changeNotificationSettings = useSetUserSettings();
     const defaultNotification = userSettingsTypes.DEFAULT_NOTIFICATIONS;
 
     const selectedDefaultNotification = useSelector<NotificationTypes>(
diff --git a/web/modals/threads/notifications/notifications-modal.react.js b/web/modals/threads/notifications/notifications-modal.react.js
--- a/web/modals/threads/notifications/notifications-modal.react.js
+++ b/web/modals/threads/notifications/notifications-modal.react.js
@@ -3,16 +3,13 @@
 import * as React from 'react';
 
 import {
-  updateSubscription,
+  useUpdateSubscription,
   updateSubscriptionActionTypes,
 } from 'lib/actions/user-actions.js';
 import { canPromoteSidebar } from 'lib/hooks/promote-sidebar.react.js';
 import { threadInfoSelector } from 'lib/selectors/thread-selectors.js';
 import { threadIsSidebar } from 'lib/shared/thread-utils.js';
-import {
-  useServerCall,
-  useDispatchActionPromise,
-} from 'lib/utils/action-utils.js';
+import { useDispatchActionPromise } from 'lib/utils/action-utils.js';
 
 import css from './notifications-modal.css';
 import AllNotifsIllustration from '../../../assets/all-notifs.react.js';
@@ -169,7 +166,7 @@
 
   const dispatchActionPromise = useDispatchActionPromise();
 
-  const callUpdateSubscription = useServerCall(updateSubscription);
+  const callUpdateSubscription = useUpdateSubscription();
 
   const onClickSave = React.useCallback(() => {
     dispatchActionPromise(