diff --git a/keyserver/src/responders/website-responders.js b/keyserver/src/responders/website-responders.js
--- a/keyserver/src/responders/website-responders.js
+++ b/keyserver/src/responders/website-responders.js
@@ -44,6 +44,7 @@
   +olmFilename: string,
   +commQueryExecutorFilename: string,
   +opaqueURL: string,
+  +backupClientFilename: string,
 };
 let assetInfo: ?AssetInfo = null;
 async function getAssetInfo() {
@@ -59,6 +60,7 @@
       olmFilename: '',
       commQueryExecutorFilename: '',
       opaqueURL: 'http://localhost:8080/opaque-ke.wasm',
+      backupClientFilename: '',
     };
     return assetInfo;
   }
@@ -83,6 +85,7 @@
       olmFilename: manifest['olm.wasm'],
       commQueryExecutorFilename: webworkersManifest['comm_query_executor.wasm'],
       opaqueURL: `compiled/${manifest['comm_opaque2_wasm_bg.wasm']}`,
+      backupClientFilename: webworkersManifest['backup_client_bg.wasm'],
     };
     return assetInfo;
   } catch {
@@ -134,6 +137,7 @@
     olmFilename,
     opaqueURL,
     commQueryExecutorFilename,
+    backupClientFilename,
   } = await assetInfoPromise;
 
   // prettier-ignore
@@ -185,6 +189,7 @@
           var baseURL = "${baseURL}";
           var olmFilename = "${olmFilename}";
           var commQueryExecutorFilename = "${commQueryExecutorFilename}";
+          var backupClientFilename = "${backupClientFilename}";
           var opaqueURL = "${opaqueURL}";
         </script>
         <script src="${jsURL}"></script>
diff --git a/package.json b/package.json
--- a/package.json
+++ b/package.json
@@ -11,7 +11,8 @@
     "keyserver/addons/rust-node-addon",
     "native/expo-modules/comm-expo-package",
     "services/electron-update-server",
-    "web/opaque-ke-wasm"
+    "web/opaque-ke-wasm",
+    "shared/backup_client"
   ],
   "scripts": {
     "clean": "yarn workspace lib clean && yarn workspace web clean && yarn workspace native clean && yarn workspace keyserver clean && yarn workspace landing clean && yarn workspace desktop clean && yarn workspace rust-node-addon clean && yarn workspace electron-update-server clean && rm -rf node_modules/",
diff --git a/web/database/database-module-provider.js b/web/database/database-module-provider.js
--- a/web/database/database-module-provider.js
+++ b/web/database/database-module-provider.js
@@ -24,6 +24,8 @@
 
 declare var baseURL: string;
 declare var commQueryExecutorFilename: string;
+declare var backupClientFilename: string;
+
 const databaseStatuses = Object.freeze({
   notRunning: 'NOT_RUNNING',
   initSuccess: 'INIT_SUCCESS',
@@ -93,6 +95,7 @@
           databaseModuleFilePath: `${origin}${baseURL}${WORKERS_MODULES_DIR_PATH}`,
           encryptionKey,
           commQueryExecutorFilename,
+          backupClientFilename,
         });
         this.status = { type: databaseStatuses.initSuccess };
         console.info('Database initialization success');
diff --git a/web/database/utils/constants.js b/web/database/utils/constants.js
--- a/web/database/utils/constants.js
+++ b/web/database/utils/constants.js
@@ -11,6 +11,7 @@
 export const WORKERS_MODULES_DIR_PATH = '/compiled/webworkers';
 
 export const DEFAULT_COMM_QUERY_EXECUTOR_FILENAME = 'comm_query_executor.wasm';
+export const DEFAULT_BACKUP_CLIENT_FILENAME = 'backup-client.wasm';
 
 export const DEFAULT_OLM_FILENAME = 'olm.wasm';
 
diff --git a/web/database/worker/db-worker.js b/web/database/worker/db-worker.js
--- a/web/database/worker/db-worker.js
+++ b/web/database/worker/db-worker.js
@@ -1,5 +1,6 @@
 // @flow
 
+import initBackupClientModule from 'backup-client';
 import localforage from 'localforage';
 
 import {
@@ -31,6 +32,7 @@
   localforageConfig,
   SQLITE_CONTENT,
   SQLITE_ENCRYPTION_KEY,
+  DEFAULT_BACKUP_CLIENT_FILENAME,
 } from '../utils/constants.js';
 import {
   clearSensitiveData,
@@ -102,6 +104,19 @@
   );
 }
 
+async function initBackupClient(
+  databaseModuleFilePath: string,
+  backupClientFilename: ?string,
+) {
+  let modulePath;
+  if (backupClientFilename) {
+    modulePath = `${databaseModuleFilePath}/${backupClientFilename}`;
+  } else {
+    modulePath = `http://localhost:8080/${DEFAULT_BACKUP_CLIENT_FILENAME}`;
+  }
+  await initBackupClientModule(modulePath);
+}
+
 async function persist() {
   persistInProgress = true;
   const module = dbModule;
@@ -148,11 +163,19 @@
 
   // database operations
   if (message.type === workerRequestMessageTypes.INIT) {
-    await initDatabase(
+    const databasePromise = initDatabase(
       message.databaseModuleFilePath,
       message.commQueryExecutorFilename,
       message.encryptionKey,
     );
+    let backupClientPromise = new Promise(resolve => resolve());
+    if (!(message.backupClientFilename === undefined)) {
+      backupClientPromise = initBackupClient(
+        message.databaseModuleFilePath,
+        message.backupClientFilename,
+      );
+    }
+    await Promise.all([databasePromise, backupClientPromise]);
     return undefined;
   } else if (message.type === workerRequestMessageTypes.CLEAR_SENSITIVE_DATA) {
     encryptionKey = null;
diff --git a/web/flow-typed/backup-client.js b/web/flow-typed/backup-client.js
new file mode 100644
--- /dev/null
+++ b/web/flow-typed/backup-client.js
@@ -0,0 +1,38 @@
+// @flow
+
+declare module 'backup-client' {
+  declare export default (string | URL) => mixed;
+
+  declare export var RequestedData: {
+    +BackupID: 0,
+    +UserKeys: 1,
+    +UserData: 2,
+  };
+
+  declare type UserIdentity = {
+    +userID: string,
+    +accessToken: string,
+    +deviceID: string,
+  };
+
+  declare type BackupDescriptor = {
+    +type: "BackupID", +backupID: string, +userIdentity: UserIdentity,
+  } | {+type: "Latest", +username: string};
+
+  declare export class BackupClient {
+    constructor(url: string): void;
+
+    downloadBackupData(
+      backupDescriptor: BackupDescriptor,
+      requestedData: $Values<typeof RequestedData>,
+    ): Promise<Uint8Array>;
+
+    downloadLogs(
+      userIdentity: UserIdentity,
+      backupID: string,
+      f: (Uint8Array) => mixed,
+    ): Promise<void>;
+
+    free(): void;
+  }
+}
diff --git a/web/package.json b/web/package.json
--- a/web/package.json
+++ b/web/package.json
@@ -42,6 +42,7 @@
     "@babel/runtime": "^7.23.7",
     "@commapp/olm": "0.1.0",
     "@commapp/opaque-ke-wasm": "npm:@commapp/opaque-ke-wasm@^0.0.3",
+    "backup-client": "0.1.0",
     "@emoji-mart/data": "^1.1.2",
     "@emoji-mart/react": "^1.1.1",
     "@fortawesome/fontawesome-svg-core": "1.2.25",
diff --git a/web/types/worker-types.js b/web/types/worker-types.js
--- a/web/types/worker-types.js
+++ b/web/types/worker-types.js
@@ -37,6 +37,7 @@
   +databaseModuleFilePath: string,
   +commQueryExecutorFilename: ?string,
   +encryptionKey?: ?SubtleCrypto$JsonWebKey,
+  +backupClientFilename?: ?string,
 };
 
 export type GenerateDatabaseEncryptionKeyRequestMessage = {
diff --git a/web/webpack.config.cjs b/web/webpack.config.cjs
--- a/web/webpack.config.cjs
+++ b/web/webpack.config.cjs
@@ -152,6 +152,14 @@
       },
     ],
   }),
+  new CopyPlugin({
+    patterns: [
+      {
+        from: 'node_modules/backup-client/web/_generated/backup_client_bg.wasm',
+        to: path.join(__dirname, 'dist', 'backup-client.wasm'),
+      },
+    ],
+  }),
 ];
 
 const prodWebWorkersPlugins = [
@@ -181,6 +189,19 @@
       },
     ],
   }),
+  new CopyPlugin({
+    patterns: [
+      {
+        from: 'node_modules/backup-client/web/_generated/backup_client_bg.wasm',
+        to: path.join(
+          __dirname,
+          'dist',
+          'webworkers',
+          'backup-client.[contenthash:12].wasm',
+        ),
+      },
+    ],
+  }),
   new WebpackManifestPlugin({
     publicPath: '',
   }),