diff --git a/keyserver/src/updaters/olm-account-updater.js b/keyserver/src/updaters/olm-account-updater.js
new file mode 100644
--- /dev/null
+++ b/keyserver/src/updaters/olm-account-updater.js
@@ -0,0 +1,112 @@
+// @flow
+
+import type { Account as OlmAccount } from '@commapp/olm';
+
+import { ServerError } from 'lib/utils/errors.js';
+import sleep from 'lib/utils/sleep.js';
+
+import { SQL, dbQuery } from '../database/database.js';
+import { unpickleOlmAccount } from '../utils/olm-utils.js';
+
+const maxOlmAccountUpdateRetriesCount = 5;
+const olmAccountUpdateRetryDelay = 2000;
+
+async function fetchCallUpdateOlmAccount<T>(
+  olmAccountType: 'content' | 'notifications',
+  callback: (account: OlmAccount) => Promise<T>,
+): Promise<T> {
+  const isContent = olmAccountType === 'content';
+  let retriesLeft = maxOlmAccountUpdateRetriesCount;
+
+  while (retriesLeft > 0) {
+    const [olmAccountResult] = await dbQuery(
+      SQL`
+        SELECT version, pickling_key, pickled_olm_account
+        FROM olm_accounts 
+        WHERE is_content = ${isContent}
+      `,
+    );
+
+    if (olmAccountResult.length === 0) {
+      throw new ServerError('missing_olm_account');
+    }
+
+    const [
+      {
+        version,
+        pickling_key: picklingKey,
+        pickled_olm_account: pickledAccount,
+      },
+    ] = olmAccountResult;
+
+    const account = await unpickleOlmAccount({
+      picklingKey,
+      pickledAccount,
+    });
+    const result = await callback(account);
+    const updatedAccount = account.pickle(picklingKey);
+
+    const [transactionResult] = await dbQuery(
+      SQL`
+        START TRANSACTION;
+
+        SELECT version INTO @currentVersion
+        FROM olm_accounts 
+        WHERE is_content = ${isContent} 
+        FOR UPDATE;
+
+        UPDATE olm_accounts
+        SET 
+          pickled_olm_account = ${updatedAccount}, 
+          version = ${version} + 1
+        WHERE version = ${version} AND is_content = ${isContent};
+        
+        COMMIT;
+
+        SELECT @currentVersion AS versionOnUpdateAttempt;
+      `,
+      { multipleStatements: true },
+    );
+    const selectResult = transactionResult.pop();
+    const [{ versionOnUpdateAttempt }] = selectResult;
+
+    if (version === versionOnUpdateAttempt) {
+      return result;
+    }
+
+    retriesLeft = retriesLeft - 1;
+    await sleep(olmAccountUpdateRetryDelay);
+  }
+
+  throw new ServerError('max_olm_account_update_retry_exceeded');
+}
+
+async function fetchOlmAccount(
+  olmAccountType: 'content' | 'notifications',
+): Promise<{
+  account: OlmAccount,
+  picklingKey: string,
+}> {
+  const isContent = olmAccountType === 'content';
+  const [olmAccountResult] = await dbQuery(
+    SQL`
+      SELECT pickling_key, pickled_olm_account 
+      FROM olm_accounts 
+      WHERE is_content = ${isContent}
+    `,
+  );
+  if (olmAccountResult.length === 0) {
+    throw new ServerError('missing_olm_account');
+  }
+  const picklingKey = olmAccountResult[0].pickling_key;
+  const pickledAccount = olmAccountResult[0].pickled_olm_account;
+
+  const account = await unpickleOlmAccount({
+    picklingKey,
+    pickledAccount,
+  });
+
+  return { account, picklingKey };
+}
+
+export { fetchCallUpdateOlmAccount, fetchOlmAccount };