diff --git a/lib/shared/dm-ops/add-members-spec.js b/lib/shared/dm-ops/add-members-spec.js
--- a/lib/shared/dm-ops/add-members-spec.js
+++ b/lib/shared/dm-ops/add-members-spec.js
@@ -11,6 +11,7 @@
 import type { DMAddMembersOperation } from '../../types/dm-ops.js';
 import { messageTypes } from '../../types/message-types-enum.js';
 import { type RawMessageInfo } from '../../types/message-types.js';
+import type { AddMembersMessageData } from '../../types/messages/add-members.js';
 import {
   minimallyEncodeMemberInfo,
   type ThickRawThreadInfo,
@@ -20,6 +21,7 @@
 import { updateTypes } from '../../types/update-types-enum.js';
 import type { ClientUpdateInfo } from '../../types/update-types.js';
 import { values } from '../../utils/objects.js';
+import { rawMessageInfoFromMessageData } from '../message-utils.js';
 import { roleIsDefaultRole, userIsMember } from '../thread-utils.js';
 
 export type AddMembersResult = {
@@ -28,21 +30,30 @@
   threadInfo: ?ThickRawThreadInfo,
 };
 
-function createAddNewMembersResults(
+function createAddNewMembersMessageDataFromDMOperation(
   dmOperation: DMAddMembersOperation,
-  viewerID: string,
-  utilities: ProcessDMOperationUtilities,
-): AddMembersResult {
-  const { editorID, time, messageID, addedUserIDs, threadID } = dmOperation;
-  const addMembersMessage = {
+): AddMembersMessageData {
+  const { editorID, time, addedUserIDs, threadID } = dmOperation;
+  return {
     type: messageTypes.ADD_MEMBERS,
-    id: messageID,
     threadID,
     creatorID: editorID,
     time,
     addedUserIDs: [...addedUserIDs],
   };
+}
 
+function createAddNewMembersResults(
+  dmOperation: DMAddMembersOperation,
+  viewerID: string,
+  utilities: ProcessDMOperationUtilities,
+): AddMembersResult {
+  const { editorID, time, messageID, addedUserIDs, threadID } = dmOperation;
+  const messageData =
+    createAddNewMembersMessageDataFromDMOperation(dmOperation);
+  const rawMessageInfos = [
+    rawMessageInfoFromMessageData(messageData, messageID),
+  ];
   const currentThreadInfo = utilities.threadInfos[threadID];
   if (!currentThreadInfo.thick) {
     return {
@@ -86,13 +97,18 @@
   ];
 
   return {
-    rawMessageInfos: [addMembersMessage],
+    rawMessageInfos,
     updateInfos,
     threadInfo: resultThreadInfo,
   };
 }
 
 const addMembersSpec: DMOperationSpec<DMAddMembersOperation> = Object.freeze({
+  notificationsCreationData: async (dmOperation: DMAddMembersOperation) => {
+    const messageData =
+      createAddNewMembersMessageDataFromDMOperation(dmOperation);
+    return { messageDatas: [messageData] };
+  },
   processDMOperation: async (
     dmOperation: DMAddMembersOperation,
     viewerID: string,
@@ -124,4 +140,8 @@
   supportsAutoRetry: true,
 });
 
-export { addMembersSpec, createAddNewMembersResults };
+export {
+  addMembersSpec,
+  createAddNewMembersResults,
+  createAddNewMembersMessageDataFromDMOperation,
+};
diff --git a/lib/shared/dm-ops/add-viewer-to-thread-members-spec.js b/lib/shared/dm-ops/add-viewer-to-thread-members-spec.js
--- a/lib/shared/dm-ops/add-viewer-to-thread-members-spec.js
+++ b/lib/shared/dm-ops/add-viewer-to-thread-members-spec.js
@@ -8,22 +8,34 @@
 import type { DMAddViewerToThreadMembersOperation } from '../../types/dm-ops.js';
 import { messageTypes } from '../../types/message-types-enum.js';
 import { messageTruncationStatus } from '../../types/message-types.js';
+import type { AddMembersMessageData } from '../../types/messages/add-members.js';
 import { updateTypes } from '../../types/update-types-enum.js';
+import { rawMessageInfoFromMessageData } from '../message-utils.js';
 
-function createAddViewerToThreadMembersResults(
+function createAddViewerToThreadMembersMessageDataFromDMOp(
   dmOperation: DMAddViewerToThreadMembersOperation,
-  viewerID: string,
-): AddMembersResult {
-  const { editorID, time, messageID, addedUserIDs, existingThreadDetails } =
-    dmOperation;
-  const addMembersMessage = {
+): AddMembersMessageData {
+  const { editorID, time, addedUserIDs, existingThreadDetails } = dmOperation;
+  return {
     type: messageTypes.ADD_MEMBERS,
-    id: messageID,
     threadID: existingThreadDetails.threadID,
     creatorID: editorID,
     time,
     addedUserIDs: [...addedUserIDs],
   };
+}
+
+function createAddViewerToThreadMembersResults(
+  dmOperation: DMAddViewerToThreadMembersOperation,
+  viewerID: string,
+): AddMembersResult {
+  const { time, messageID, addedUserIDs, existingThreadDetails } = dmOperation;
+  const messageData =
+    createAddViewerToThreadMembersMessageDataFromDMOp(dmOperation);
+
+  const rawMessageInfos = [
+    rawMessageInfoFromMessageData(messageData, messageID),
+  ];
 
   const resultThreadInfo = createThickRawThreadInfo(
     {
@@ -38,7 +50,7 @@
       id: uuid.v4(),
       time,
       threadInfo: resultThreadInfo,
-      rawMessageInfos: [addMembersMessage],
+      rawMessageInfos,
       truncationStatus: messageTruncationStatus.EXHAUSTIVE,
       rawEntryInfos: [],
     },
@@ -52,6 +64,13 @@
 
 const addViewerToThreadMembersSpec: DMOperationSpec<DMAddViewerToThreadMembersOperation> =
   Object.freeze({
+    notificationsCreationData: async (
+      dmOperation: DMAddViewerToThreadMembersOperation,
+    ) => {
+      const messageData =
+        createAddViewerToThreadMembersMessageDataFromDMOp(dmOperation);
+      return { messageDatas: [messageData] };
+    },
     processDMOperation: async (
       dmOperation: DMAddViewerToThreadMembersOperation,
       viewerID: string,
@@ -78,4 +97,8 @@
     supportsAutoRetry: true,
   });
 
-export { addViewerToThreadMembersSpec, createAddViewerToThreadMembersResults };
+export {
+  addViewerToThreadMembersSpec,
+  createAddViewerToThreadMembersResults,
+  createAddViewerToThreadMembersMessageDataFromDMOp,
+};
diff --git a/lib/shared/dm-ops/change-thread-settings-and-add-viewer-spec.js b/lib/shared/dm-ops/change-thread-settings-and-add-viewer-spec.js
--- a/lib/shared/dm-ops/change-thread-settings-and-add-viewer-spec.js
+++ b/lib/shared/dm-ops/change-thread-settings-and-add-viewer-spec.js
@@ -3,13 +3,19 @@
 import {
   addViewerToThreadMembersSpec,
   createAddViewerToThreadMembersResults,
+  createAddViewerToThreadMembersMessageDataFromDMOp,
 } from './add-viewer-to-thread-members-spec.js';
-import { processChangeSettingsOperation } from './change-thread-settings-spec.js';
+import {
+  processChangeSettingsOperation,
+  createChangeSettingsMessageDatasAndUpdate,
+} from './change-thread-settings-spec.js';
 import type {
   DMOperationSpec,
   ProcessDMOperationUtilities,
 } from './dm-op-spec.js';
 import type { DMChangeThreadSettingsAndAddViewerOperation } from '../../types/dm-ops.js';
+import type { MessageData } from '../../types/message-types.js';
+import { values } from '../../utils/objects.js';
 
 function createAddViewerAndMembersOperation(
   dmOperation: DMChangeThreadSettingsAndAddViewerOperation,
@@ -43,6 +49,25 @@
 
 const changeThreadSettingsAndAddViewerSpec: DMOperationSpec<DMChangeThreadSettingsAndAddViewerOperation> =
   Object.freeze({
+    notificationsCreationData: async (
+      dmOperation: DMChangeThreadSettingsAndAddViewerOperation,
+    ) => {
+      const messageDatas: Array<MessageData> = [];
+      const addNewMembersOperation =
+        createAddViewerAndMembersOperation(dmOperation);
+      if (addNewMembersOperation) {
+        const addNewMembersMessageData =
+          createAddViewerToThreadMembersMessageDataFromDMOp(
+            addNewMembersOperation,
+          );
+        messageDatas.push(addNewMembersMessageData);
+      }
+
+      const { fieldNameToMessageData } =
+        createChangeSettingsMessageDatasAndUpdate(dmOperation);
+      messageDatas.push(...values(fieldNameToMessageData));
+      return { messageDatas };
+    },
     processDMOperation: async (
       dmOperation: DMChangeThreadSettingsAndAddViewerOperation,
       viewerID: string,
diff --git a/lib/shared/dm-ops/change-thread-settings-spec.js b/lib/shared/dm-ops/change-thread-settings-spec.js
--- a/lib/shared/dm-ops/change-thread-settings-spec.js
+++ b/lib/shared/dm-ops/change-thread-settings-spec.js
@@ -6,6 +6,7 @@
 import {
   type AddMembersResult,
   createAddNewMembersResults,
+  createAddNewMembersMessageDataFromDMOperation,
 } from './add-members-spec.js';
 import type {
   DMOperationSpec,
@@ -15,19 +16,19 @@
   DMChangeThreadSettingsAndAddViewerOperation,
   DMChangeThreadSettingsOperation,
   DMOperationResult,
+  DMThreadSettingsChangesBase,
 } from '../../types/dm-ops.js';
+import type { MessageData, RawMessageInfo } from '../../types/message-types';
 import { messageTypes } from '../../types/message-types-enum.js';
-import type { RawMessageInfo } from '../../types/message-types.js';
+import type { ChangeSettingsMessageData } from '../../types/messages/change-settings.js';
 import type { RawThreadInfo } from '../../types/minimally-encoded-thread-permissions-types.js';
-import type { LegacyRawThreadInfo } from '../../types/thread-types.js';
 import { updateTypes } from '../../types/update-types-enum.js';
 import type { ClientUpdateInfo } from '../../types/update-types.js';
 import { values } from '../../utils/objects.js';
+import { rawMessageInfoFromMessageData } from '../message-utils.js';
 
-function processAddMembersOperation(
+function createAddMembersOperation(
   dmOperation: DMChangeThreadSettingsOperation,
-  viewerID: string,
-  utilities: ProcessDMOperationUtilities,
 ) {
   const { editorID, time, messageIDsPrefix, changes, threadID } = dmOperation;
   const newMemberIDs =
@@ -37,7 +38,7 @@
   if (!changes.newMemberIDs || changes.newMemberIDs.length === 0) {
     return null;
   }
-  const operation = {
+  return {
     type: 'add_members',
     editorID,
     time,
@@ -45,87 +46,127 @@
     addedUserIDs: newMemberIDs,
     threadID,
   };
+}
+
+function processAddMembersOperation(
+  dmOperation: DMChangeThreadSettingsOperation,
+  viewerID: string,
+  utilities: ProcessDMOperationUtilities,
+) {
+  const operation = createAddMembersOperation(dmOperation);
+  if (!operation) {
+    return null;
+  }
   return createAddNewMembersResults(operation, viewerID, utilities);
 }
 
-function processChangeSettingsOperation(
+function getThreadIDFromChangeThreadSettingsDMOp(
   dmOperation:
     | DMChangeThreadSettingsOperation
     | DMChangeThreadSettingsAndAddViewerOperation,
-  viewerID: string,
-  utilities: ProcessDMOperationUtilities,
-  addMembersResult: ?AddMembersResult,
-): DMOperationResult {
-  const { editorID, time, changes, messageIDsPrefix } = dmOperation;
-  const { name, description, color, avatar } = changes;
-  const threadID =
-    dmOperation.type === 'change_thread_settings'
-      ? dmOperation.threadID
-      : dmOperation.existingThreadDetails.threadID;
-
-  let threadInfoToUpdate: ?(RawThreadInfo | LegacyRawThreadInfo) =
-    utilities.threadInfos[threadID];
-  const updateInfos: Array<ClientUpdateInfo> = [];
-  const rawMessageInfos: Array<RawMessageInfo> = [];
-
-  if (addMembersResult) {
-    if (addMembersResult.threadInfo) {
-      threadInfoToUpdate = addMembersResult.threadInfo;
-    }
-    updateInfos.push(...addMembersResult.updateInfos);
-    rawMessageInfos.push(...addMembersResult.rawMessageInfos);
-  }
+): string {
+  return dmOperation.type === 'change_thread_settings'
+    ? dmOperation.threadID
+    : dmOperation.existingThreadDetails.threadID;
+}
 
-  invariant(threadInfoToUpdate?.thick, 'Thread should be thick');
+function createChangeSettingsMessageDatasAndUpdate(
+  dmOperation:
+    | DMChangeThreadSettingsOperation
+    | DMChangeThreadSettingsAndAddViewerOperation,
+): {
+  +fieldNameToMessageData: { +[fieldName: string]: ChangeSettingsMessageData },
+  +threadInfoUpdate: DMThreadSettingsChangesBase,
+} {
+  const { changes, editorID, time } = dmOperation;
+  const { name, description, color, avatar } = changes;
+  const threadID = getThreadIDFromChangeThreadSettingsDMOp(dmOperation);
 
-  const changedFields: { [string]: string | number } = {};
+  const threadInfoUpdate: { ...DMThreadSettingsChangesBase } = {};
 
   if (name !== undefined && name !== null) {
-    changedFields.name = name;
-    threadInfoToUpdate = {
-      ...threadInfoToUpdate,
-      name,
-    };
+    threadInfoUpdate.name = name;
   }
 
   if (description !== undefined && description !== null) {
-    changedFields.description = description;
-    threadInfoToUpdate = {
-      ...threadInfoToUpdate,
-      description,
-    };
+    threadInfoUpdate.description = description;
   }
 
   if (color) {
-    changedFields.color = color;
-    threadInfoToUpdate = {
-      ...threadInfoToUpdate,
-      color,
-    };
+    threadInfoUpdate.color = color;
   }
 
   if (avatar) {
-    changedFields.avatar = JSON.stringify(avatar);
-    threadInfoToUpdate = {
-      ...threadInfoToUpdate,
-      avatar,
-    };
+    threadInfoUpdate.avatar;
   }
 
-  for (const fieldName in changedFields) {
-    const newValue = changedFields[fieldName];
-    rawMessageInfos.push({
+  const fieldNameToMessageData: {
+    [fieldName: string]: ChangeSettingsMessageData,
+  } = {};
+
+  const { avatar: avatarObject, ...rest } = threadInfoUpdate;
+  const normalizedThreadInfoUpdate = avatarObject
+    ? { ...rest, avatar: JSON.stringify(avatarObject) }
+    : { ...rest };
+
+  for (const fieldName in normalizedThreadInfoUpdate) {
+    const value = normalizedThreadInfoUpdate[fieldName];
+    fieldNameToMessageData[fieldName] = {
       type: messageTypes.CHANGE_SETTINGS,
       threadID,
       creatorID: editorID,
       time,
       field: fieldName,
-      value: newValue,
-      id: `${messageIDsPrefix}/${fieldName}`,
-    });
+      value: value,
+    };
   }
 
-  if (values(changedFields).length > 0) {
+  return { fieldNameToMessageData, threadInfoUpdate };
+}
+
+function processChangeSettingsOperation(
+  dmOperation:
+    | DMChangeThreadSettingsOperation
+    | DMChangeThreadSettingsAndAddViewerOperation,
+  viewerID: string,
+  utilities: ProcessDMOperationUtilities,
+  addMembersResult: ?AddMembersResult,
+): DMOperationResult {
+  const { time, messageIDsPrefix } = dmOperation;
+  const threadID = getThreadIDFromChangeThreadSettingsDMOp(dmOperation);
+
+  let threadInfoToUpdate: ?RawThreadInfo = utilities.threadInfos[threadID];
+  const updateInfos: Array<ClientUpdateInfo> = [];
+  const rawMessageInfos: Array<RawMessageInfo> = [];
+
+  if (addMembersResult) {
+    if (addMembersResult.threadInfo) {
+      threadInfoToUpdate = addMembersResult.threadInfo;
+    }
+    updateInfos.push(...addMembersResult.updateInfos);
+    rawMessageInfos.push(...addMembersResult.rawMessageInfos);
+  }
+
+  invariant(threadInfoToUpdate?.thick, 'Thread should be thick');
+  const { fieldNameToMessageData, threadInfoUpdate } =
+    createChangeSettingsMessageDatasAndUpdate(dmOperation);
+
+  const fieldNameToMessageDataPairs = Object.entries(fieldNameToMessageData);
+  rawMessageInfos.push(
+    ...fieldNameToMessageDataPairs.map(([fieldName, messageData]) =>
+      rawMessageInfoFromMessageData(
+        messageData,
+        `${messageIDsPrefix}/${fieldName}`,
+      ),
+    ),
+  );
+
+  threadInfoToUpdate = {
+    ...threadInfoToUpdate,
+    ...threadInfoUpdate,
+  };
+
+  if (fieldNameToMessageDataPairs.length > 0) {
     updateInfos.push({
       type: updateTypes.UPDATE_THREAD,
       id: uuid.v4(),
@@ -142,6 +183,22 @@
 
 const changeThreadSettingsSpec: DMOperationSpec<DMChangeThreadSettingsOperation> =
   Object.freeze({
+    notificationsCreationData: async (
+      dmOperation: DMChangeThreadSettingsOperation,
+    ) => {
+      const messageDatas: Array<MessageData> = [];
+      const addNewMembersOperation = createAddMembersOperation(dmOperation);
+      if (addNewMembersOperation) {
+        const addNewMembersMessageData =
+          createAddNewMembersMessageDataFromDMOperation(addNewMembersOperation);
+        messageDatas.push(addNewMembersMessageData);
+      }
+
+      const { fieldNameToMessageData } =
+        createChangeSettingsMessageDatasAndUpdate(dmOperation);
+      messageDatas.push(...values(fieldNameToMessageData));
+      return { messageDatas };
+    },
     processDMOperation: async (
       dmOperation: DMChangeThreadSettingsOperation,
       viewerID: string,
@@ -179,4 +236,8 @@
     supportsAutoRetry: true,
   });
 
-export { changeThreadSettingsSpec, processChangeSettingsOperation };
+export {
+  changeThreadSettingsSpec,
+  processChangeSettingsOperation,
+  createChangeSettingsMessageDatasAndUpdate,
+};
diff --git a/lib/shared/dm-ops/create-sidebar-spec.js b/lib/shared/dm-ops/create-sidebar-spec.js
--- a/lib/shared/dm-ops/create-sidebar-spec.js
+++ b/lib/shared/dm-ops/create-sidebar-spec.js
@@ -15,10 +15,81 @@
 } from '../../types/message-types.js';
 import { threadTypes } from '../../types/thread-types-enum.js';
 import { updateTypes } from '../../types/update-types-enum.js';
-import { isInvalidSidebarSource } from '../message-utils.js';
+import { generatePendingThreadColor } from '../color-utils.js';
+import {
+  isInvalidSidebarSource,
+  rawMessageInfoFromMessageData,
+} from '../message-utils.js';
+
+async function createMessageDatasFromDMOperation(
+  dmOperation: DMCreateSidebarOperation,
+  utilities: ProcessDMOperationUtilities,
+  threadColor?: string,
+) {
+  const {
+    threadID,
+    creatorID,
+    time,
+    parentThreadID,
+    memberIDs,
+    sourceMessageID,
+  } = dmOperation;
+
+  const allMemberIDs = [creatorID, ...memberIDs];
+  const color = threadColor ?? generatePendingThreadColor(allMemberIDs);
+  const sourceMessage = await utilities.fetchMessage(sourceMessageID);
+
+  if (!sourceMessage) {
+    throw new Error(
+      `could not find sourceMessage ${sourceMessageID}... probably ` +
+        'joined thick thread ${parentThreadID} after its creation',
+    );
+  }
+  if (isInvalidSidebarSource(sourceMessage)) {
+    throw new Error(
+      `sourceMessage ${sourceMessageID} is an invalid sidebar source`,
+    );
+  }
+
+  const sidebarSourceMessageData = {
+    type: messageTypes.SIDEBAR_SOURCE,
+    threadID,
+    creatorID,
+    time,
+    sourceMessage: sourceMessage,
+  };
+
+  const createSidebarMessageData = {
+    type: messageTypes.CREATE_SIDEBAR,
+    threadID,
+    creatorID,
+    time: time + 1,
+    sourceMessageAuthorID: sourceMessage.creatorID,
+    initialThreadState: {
+      parentThreadID,
+      color,
+      memberIDs: allMemberIDs,
+    },
+  };
+
+  return {
+    sidebarSourceMessageData,
+    createSidebarMessageData,
+  };
+}
 
 const createSidebarSpec: DMOperationSpec<DMCreateSidebarOperation> =
   Object.freeze({
+    notificationsCreationData: async (
+      dmOperation: DMCreateSidebarOperation,
+      utilities: ProcessDMOperationUtilities,
+    ) => {
+      const { sidebarSourceMessageData, createSidebarMessageData } =
+        await createMessageDatasFromDMOperation(dmOperation, utilities);
+      return {
+        messageDatas: [sidebarSourceMessageData, createSidebarMessageData],
+      };
+    },
     processDMOperation: async (
       dmOperation: DMCreateSidebarOperation,
       viewerID: string,
@@ -52,41 +123,25 @@
         viewerID,
       );
 
-      const sourceMessage = await utilities.fetchMessage(sourceMessageID);
-      if (!sourceMessage) {
-        throw new Error(
-          `could not find sourceMessage ${sourceMessageID}... probably ` +
-            'joined thick thread ${parentThreadID} after its creation',
+      const { sidebarSourceMessageData, createSidebarMessageData } =
+        await createMessageDatasFromDMOperation(
+          dmOperation,
+          utilities,
+          rawThreadInfo.color,
         );
-      }
-      if (isInvalidSidebarSource(sourceMessage)) {
-        throw new Error(
-          `sourceMessage ${sourceMessageID} is an invalid sidebar source`,
-        );
-      }
+
+      const sidebarSourceMessageInfo = rawMessageInfoFromMessageData(
+        sidebarSourceMessageData,
+        newSidebarSourceMessageID,
+      );
+      const createSidebarMessageInfo = rawMessageInfoFromMessageData(
+        createSidebarMessageData,
+        newCreateSidebarMessageID,
+      );
 
       const rawMessageInfos: Array<RawMessageInfo> = [
-        {
-          type: messageTypes.SIDEBAR_SOURCE,
-          id: newSidebarSourceMessageID,
-          threadID,
-          creatorID,
-          time,
-          sourceMessage,
-        },
-        {
-          type: messageTypes.CREATE_SIDEBAR,
-          id: newCreateSidebarMessageID,
-          threadID,
-          creatorID,
-          time: time + 1,
-          sourceMessageAuthorID: sourceMessage.creatorID,
-          initialThreadState: {
-            parentThreadID,
-            color: rawThreadInfo.color,
-            memberIDs: allMemberIDs,
-          },
-        },
+        sidebarSourceMessageInfo,
+        createSidebarMessageInfo,
       ];
 
       const threadJoinUpdateInfo = {
diff --git a/lib/shared/dm-ops/create-thread-spec.js b/lib/shared/dm-ops/create-thread-spec.js
--- a/lib/shared/dm-ops/create-thread-spec.js
+++ b/lib/shared/dm-ops/create-thread-spec.js
@@ -14,10 +14,7 @@
   DMCreateThreadOperation,
 } from '../../types/dm-ops.js';
 import { messageTypes } from '../../types/message-types-enum.js';
-import {
-  type RawMessageInfo,
-  messageTruncationStatus,
-} from '../../types/message-types.js';
+import { messageTruncationStatus } from '../../types/message-types.js';
 import {
   type ThickRawThreadInfo,
   type RoleInfo,
@@ -31,6 +28,7 @@
 import type { ThickMemberInfo } from '../../types/thread-types.js';
 import { updateTypes } from '../../types/update-types-enum.js';
 import { generatePendingThreadColor } from '../color-utils.js';
+import { rawMessageInfoFromMessageData } from '../message-utils.js';
 
 function createRoleAndPermissionForThickThreads(
   threadType: ThickThreadType,
@@ -126,8 +124,31 @@
   return newThread;
 }
 
+function createMessageDataFromDMOperation(
+  dmOperation: DMCreateThreadOperation,
+) {
+  const { threadID, creatorID, time, threadType, memberIDs } = dmOperation;
+  const allMemberIDs = [creatorID, ...memberIDs];
+  const color = generatePendingThreadColor(allMemberIDs);
+  return {
+    type: messageTypes.CREATE_THREAD,
+    threadID,
+    creatorID,
+    time,
+    initialThreadState: {
+      type: threadType,
+      color,
+      memberIDs: allMemberIDs,
+    },
+  };
+}
+
 const createThreadSpec: DMOperationSpec<DMCreateThreadOperation> =
   Object.freeze({
+    notificationsCreationData: async (dmOperation: DMCreateThreadOperation) => {
+      const messageData = createMessageDataFromDMOperation(dmOperation);
+      return { messageDatas: [messageData] };
+    },
     processDMOperation: async (
       dmOperation: DMCreateThreadOperation,
       viewerID: string,
@@ -155,19 +176,9 @@
         viewerID,
       );
 
-      const rawMessageInfos: Array<RawMessageInfo> = [
-        {
-          type: messageTypes.CREATE_THREAD,
-          id: newMessageID,
-          threadID,
-          creatorID,
-          time,
-          initialThreadState: {
-            type: threadType,
-            color: rawThreadInfo.color,
-            memberIDs: allMemberIDs,
-          },
-        },
+      const messageData = createMessageDataFromDMOperation(dmOperation);
+      const rawMessageInfos = [
+        rawMessageInfoFromMessageData(messageData, newMessageID),
       ];
 
       const threadJoinUpdateInfo = {
diff --git a/lib/shared/dm-ops/dm-op-spec.js b/lib/shared/dm-ops/dm-op-spec.js
--- a/lib/shared/dm-ops/dm-op-spec.js
+++ b/lib/shared/dm-ops/dm-op-spec.js
@@ -2,6 +2,7 @@
 
 import type { DMOperation, DMOperationResult } from '../../types/dm-ops.js';
 import type { RawMessageInfo } from '../../types/message-types.js';
+import type { NotificationsCreationData } from '../../types/notif-types.js';
 import type { RawThreadInfos } from '../../types/thread-types.js';
 
 export type ProcessDMOperationUtilities = {
@@ -11,6 +12,10 @@
 };
 
 export type DMOperationSpec<DMOp: DMOperation> = {
+  +notificationsCreationData?: (
+    dmOp: DMOp,
+    utilities: ProcessDMOperationUtilities,
+  ) => Promise<NotificationsCreationData>,
   +processDMOperation: (
     dmOp: DMOp,
     viewerID: string,
diff --git a/lib/shared/dm-ops/join-thread-spec.js b/lib/shared/dm-ops/join-thread-spec.js
--- a/lib/shared/dm-ops/join-thread-spec.js
+++ b/lib/shared/dm-ops/join-thread-spec.js
@@ -23,9 +23,24 @@
 import { updateTypes } from '../../types/update-types-enum.js';
 import type { ClientUpdateInfo } from '../../types/update-types.js';
 import { values } from '../../utils/objects.js';
+import { rawMessageInfoFromMessageData } from '../message-utils.js';
 import { roleIsDefaultRole, userIsMember } from '../thread-utils.js';
 
+function createMessageDataFromDMOperation(dmOperation: DMJoinThreadOperation) {
+  const { joinerID, time, existingThreadDetails } = dmOperation;
+  return {
+    type: messageTypes.JOIN_THREAD,
+    threadID: existingThreadDetails.threadID,
+    creatorID: joinerID,
+    time,
+  };
+}
+
 const joinThreadSpec: DMOperationSpec<DMJoinThreadOperation> = Object.freeze({
+  notificationsCreationData: async (dmOperation: DMJoinThreadOperation) => {
+    const messageData = createMessageDataFromDMOperation(dmOperation);
+    return { messageDatas: [messageData] };
+  },
   processDMOperation: async (
     dmOperation: DMJoinThreadOperation,
     viewerID: string,
@@ -36,17 +51,14 @@
     const currentThreadInfo =
       utilities.threadInfos[existingThreadDetails.threadID];
 
-    const joinThreadMessage = {
-      type: messageTypes.JOIN_THREAD,
-      id: messageID,
-      threadID: existingThreadDetails.threadID,
-      creatorID: joinerID,
-      time,
-    };
+    const messageData = createMessageDataFromDMOperation(dmOperation);
+    const joinThreadMessageInfos = [
+      rawMessageInfoFromMessageData(messageData, messageID),
+    ];
 
     if (userIsMember(currentThreadInfo, joinerID)) {
       return {
-        rawMessageInfos: [joinThreadMessage],
+        rawMessageInfos: joinThreadMessageInfos,
         updateInfos: [],
       };
     }
@@ -66,14 +78,14 @@
         id: uuid.v4(),
         time,
         threadInfo: newThreadInfo,
-        rawMessageInfos: [joinThreadMessage],
+        rawMessageInfos: joinThreadMessageInfos,
         truncationStatus: messageTruncationStatus.EXHAUSTIVE,
         rawEntryInfos: [],
       });
     } else {
       invariant(currentThreadInfo.thick, 'Thread should be thick');
 
-      rawMessageInfos.push(joinThreadMessage);
+      rawMessageInfos.push(...joinThreadMessageInfos);
       const defaultRoleID = values(currentThreadInfo.roles).find(role =>
         roleIsDefaultRole(role),
       )?.id;
diff --git a/lib/shared/dm-ops/leave-thread-spec.js b/lib/shared/dm-ops/leave-thread-spec.js
--- a/lib/shared/dm-ops/leave-thread-spec.js
+++ b/lib/shared/dm-ops/leave-thread-spec.js
@@ -12,9 +12,24 @@
 import { threadTypes } from '../../types/thread-types-enum.js';
 import { updateTypes } from '../../types/update-types-enum.js';
 import type { ClientUpdateInfo } from '../../types/update-types.js';
+import { rawMessageInfoFromMessageData } from '../message-utils.js';
 import { userIsMember } from '../thread-utils.js';
 
+function createMessageDataFromDMOperation(dmOperation: DMLeaveThreadOperation) {
+  const { editorID, time, threadID } = dmOperation;
+  return {
+    type: messageTypes.LEAVE_THREAD,
+    threadID,
+    creatorID: editorID,
+    time,
+  };
+}
+
 const leaveThreadSpec: DMOperationSpec<DMLeaveThreadOperation> = Object.freeze({
+  notificationsCreationData: async (dmOperation: DMLeaveThreadOperation) => {
+    const messageData = createMessageDataFromDMOperation(dmOperation);
+    return { messageDatas: [messageData] };
+  },
   processDMOperation: async (
     dmOperation: DMLeaveThreadOperation,
     viewerID: string,
@@ -25,13 +40,10 @@
     const threadInfo = utilities.threadInfos[threadID];
     invariant(threadInfo.thick, 'Thread should be thick');
 
-    const leaveThreadMessage = {
-      type: messageTypes.LEAVE_THREAD,
-      id: messageID,
-      threadID,
-      creatorID: editorID,
-      time,
-    };
+    const messageData = createMessageDataFromDMOperation(dmOperation);
+    const rawMessageInfos = [
+      rawMessageInfoFromMessageData(messageData, messageID),
+    ];
 
     const updateInfos: Array<ClientUpdateInfo> = [];
     if (
@@ -61,7 +73,7 @@
     }
 
     return {
-      rawMessageInfos: [leaveThreadMessage],
+      rawMessageInfos,
       updateInfos,
     };
   },
diff --git a/lib/shared/dm-ops/remove-members-spec.js b/lib/shared/dm-ops/remove-members-spec.js
--- a/lib/shared/dm-ops/remove-members-spec.js
+++ b/lib/shared/dm-ops/remove-members-spec.js
@@ -12,28 +12,43 @@
 import { threadTypes } from '../../types/thread-types-enum.js';
 import { updateTypes } from '../../types/update-types-enum.js';
 import type { ClientUpdateInfo } from '../../types/update-types.js';
+import { rawMessageInfoFromMessageData } from '../message-utils.js';
+
+function createMessageDataFromDMOperation(
+  dmOperation: DMRemoveMembersOperation,
+) {
+  const { editorID, time, threadID, removedUserIDs } = dmOperation;
+  return {
+    type: messageTypes.REMOVE_MEMBERS,
+    threadID,
+    time,
+    creatorID: editorID,
+    removedUserIDs: [...removedUserIDs],
+  };
+}
 
 const removeMembersSpec: DMOperationSpec<DMRemoveMembersOperation> =
   Object.freeze({
+    notificationsCreationData: async (
+      dmOperation: DMRemoveMembersOperation,
+    ) => {
+      const messageData = createMessageDataFromDMOperation(dmOperation);
+      return { messageDatas: [messageData] };
+    },
     processDMOperation: async (
       dmOperation: DMRemoveMembersOperation,
       viewerID: string,
       utilities: ProcessDMOperationUtilities,
     ) => {
-      const { editorID, time, messageID, threadID, removedUserIDs } =
-        dmOperation;
+      const { time, messageID, threadID, removedUserIDs } = dmOperation;
 
       const threadInfo = utilities.threadInfos[threadID];
       invariant(threadInfo.thick, 'Thread should be thick');
 
-      const removeMembersMessage = {
-        type: messageTypes.REMOVE_MEMBERS,
-        id: messageID,
-        threadID,
-        time,
-        creatorID: editorID,
-        removedUserIDs: [...removedUserIDs],
-      };
+      const messageData = createMessageDataFromDMOperation(dmOperation);
+      const rawMessageInfos = [
+        rawMessageInfoFromMessageData(messageData, messageID),
+      ];
 
       const removedUserIDsSet = new Set(removedUserIDs);
       const viewerIsRemoved = removedUserIDsSet.has(viewerID);
@@ -65,7 +80,7 @@
         });
       }
       return {
-        rawMessageInfos: [removeMembersMessage],
+        rawMessageInfos,
         updateInfos,
       };
     },
diff --git a/lib/shared/dm-ops/send-edit-message-spec.js b/lib/shared/dm-ops/send-edit-message-spec.js
--- a/lib/shared/dm-ops/send-edit-message-spec.js
+++ b/lib/shared/dm-ops/send-edit-message-spec.js
@@ -6,24 +6,39 @@
 } from './dm-op-spec.js';
 import type { DMSendEditMessageOperation } from '../../types/dm-ops.js';
 import { messageTypes } from '../../types/message-types-enum.js';
+import { rawMessageInfoFromMessageData } from '../message-utils.js';
+
+function createMessageDataFromDMOperation(
+  dmOperation: DMSendEditMessageOperation,
+) {
+  const { threadID, creatorID, time, targetMessageID, text } = dmOperation;
+  return {
+    type: messageTypes.EDIT_MESSAGE,
+    threadID,
+    creatorID,
+    time,
+    targetMessageID,
+    text,
+  };
+}
 
 const sendEditMessageSpec: DMOperationSpec<DMSendEditMessageOperation> =
   Object.freeze({
+    notificationsCreationData: async (
+      dmOperation: DMSendEditMessageOperation,
+    ) => {
+      const messageData = createMessageDataFromDMOperation(dmOperation);
+      return { messageDatas: [messageData] };
+    },
     processDMOperation: async (dmOperation: DMSendEditMessageOperation) => {
-      const { threadID, creatorID, time, messageID, targetMessageID, text } =
-        dmOperation;
-      const editMessage = {
-        type: messageTypes.EDIT_MESSAGE,
-        id: messageID,
-        threadID,
-        creatorID,
-        time,
-        targetMessageID,
-        text,
-      };
+      const { messageID } = dmOperation;
+      const messageData = createMessageDataFromDMOperation(dmOperation);
+      const rawMessageInfos = [
+        rawMessageInfoFromMessageData(messageData, messageID),
+      ];
 
       return {
-        rawMessageInfos: [editMessage],
+        rawMessageInfos,
         updateInfos: [],
       };
     },
diff --git a/lib/shared/dm-ops/send-reaction-message-spec.js b/lib/shared/dm-ops/send-reaction-message-spec.js
--- a/lib/shared/dm-ops/send-reaction-message-spec.js
+++ b/lib/shared/dm-ops/send-reaction-message-spec.js
@@ -6,32 +6,41 @@
 } from './dm-op-spec.js';
 import type { DMSendReactionMessageOperation } from '../../types/dm-ops.js';
 import { messageTypes } from '../../types/message-types-enum.js';
+import { rawMessageInfoFromMessageData } from '../message-utils.js';
+
+function createMessageDataFromDMOperation(
+  dmOperation: DMSendReactionMessageOperation,
+) {
+  const { threadID, creatorID, time, targetMessageID, reaction, action } =
+    dmOperation;
+  return {
+    type: messageTypes.REACTION,
+    threadID,
+    creatorID,
+    time,
+    targetMessageID,
+    reaction,
+    action,
+  };
+}
 
 const sendReactionMessageSpec: DMOperationSpec<DMSendReactionMessageOperation> =
   Object.freeze({
+    notificationsCreationData: async (
+      dmOperation: DMSendReactionMessageOperation,
+    ) => {
+      const messageData = createMessageDataFromDMOperation(dmOperation);
+      return { messageDatas: [messageData] };
+    },
     processDMOperation: async (dmOperation: DMSendReactionMessageOperation) => {
-      const {
-        threadID,
-        creatorID,
-        time,
-        messageID,
-        targetMessageID,
-        reaction,
-        action,
-      } = dmOperation;
-      const reactionMessage = {
-        type: messageTypes.REACTION,
-        id: messageID,
-        threadID,
-        creatorID,
-        time,
-        targetMessageID,
-        reaction,
-        action,
-      };
+      const { messageID } = dmOperation;
+      const messageData = createMessageDataFromDMOperation(dmOperation);
+      const rawMessageInfos = [
+        rawMessageInfoFromMessageData(messageData, messageID),
+      ];
 
       return {
-        rawMessageInfos: [reactionMessage],
+        rawMessageInfos,
         updateInfos: [],
       };
     },
diff --git a/lib/shared/dm-ops/send-text-message-spec.js b/lib/shared/dm-ops/send-text-message-spec.js
--- a/lib/shared/dm-ops/send-text-message-spec.js
+++ b/lib/shared/dm-ops/send-text-message-spec.js
@@ -7,22 +7,38 @@
 import type { DMSendTextMessageOperation } from '../../types/dm-ops.js';
 import { messageTypes } from '../../types/message-types-enum.js';
 import type { ClientUpdateInfo } from '../../types/update-types.js';
+import { rawMessageInfoFromMessageData } from '../message-utils.js';
+
+function createMessageDataFromDMOperation(
+  dmOperation: DMSendTextMessageOperation,
+) {
+  const { threadID, creatorID, time, text } = dmOperation;
+  return {
+    type: messageTypes.TEXT,
+    threadID,
+    creatorID,
+    time,
+    text,
+  };
+}
 
 const sendTextMessageSpec: DMOperationSpec<DMSendTextMessageOperation> =
   Object.freeze({
+    notificationsCreationData: async (
+      dmOperation: DMSendTextMessageOperation,
+    ) => {
+      const messageData = createMessageDataFromDMOperation(dmOperation);
+      return { messageDatas: [messageData] };
+    },
     processDMOperation: async (dmOperation: DMSendTextMessageOperation) => {
-      const { threadID, creatorID, time, messageID, text } = dmOperation;
-      const textMessage = {
-        type: messageTypes.TEXT,
-        id: messageID,
-        threadID,
-        creatorID,
-        time,
-        text,
-      };
+      const { messageID } = dmOperation;
+      const messageData = createMessageDataFromDMOperation(dmOperation);
+      const rawMessageInfos = [
+        rawMessageInfoFromMessageData(messageData, messageID),
+      ];
       const updateInfos: Array<ClientUpdateInfo> = [];
       return {
-        rawMessageInfos: [textMessage],
+        rawMessageInfos,
         updateInfos,
       };
     },
diff --git a/lib/types/dm-ops.js b/lib/types/dm-ops.js
--- a/lib/types/dm-ops.js
+++ b/lib/types/dm-ops.js
@@ -263,18 +263,25 @@
     removedUserIDs: t.list(tUserID),
   });
 
+export type DMThreadSettingsChangesBase = {
+  +name?: string,
+  +description?: string,
+  +color?: string,
+  +avatar?: ClientAvatar,
+};
+
+type DMThreadSettingsChanges = $ReadOnly<{
+  ...DMThreadSettingsChangesBase,
+  +newMemberIDs?: $ReadOnlyArray<string>,
+}>;
+
 type DMChangeThreadSettingsBase = {
   +editorID: string,
   +time: number,
-  +changes: {
-    +name?: string,
-    +description?: string,
-    +color?: string,
-    +newMemberIDs?: $ReadOnlyArray<string>,
-    +avatar?: ClientAvatar,
-  },
+  +changes: DMThreadSettingsChanges,
   +messageIDsPrefix: string,
 };
+
 const dmChangeThreadSettingsBaseValidatorShape: TStructProps<DMChangeThreadSettingsBase> =
   {
     editorID: tUserID,