diff --git a/packages/backend/src/connectionManager.ts b/packages/backend/src/connectionManager.ts
index 8b54fa4d..ee17543a 100644
--- a/packages/backend/src/connectionManager.ts
+++ b/packages/backend/src/connectionManager.ts
@@ -7,7 +7,7 @@ import { Job, Queue, ReservedJob, Worker } from "groupmq";
 import { Redis } from 'ioredis';
 import { compileAzureDevOpsConfig, compileBitbucketConfig, compileGenericGitHostConfig, compileGerritConfig, compileGiteaConfig, compileGithubConfig, compileGitlabConfig } from "./repoCompileUtils.js";
 import { Settings } from "./types.js";
-import { groupmqLifecycleExceptionWrapper } from "./utils.js";
+import { groupmqLifecycleExceptionWrapper, setIntervalAsync } from "./utils.js";
 import { syncSearchContexts } from "./ee/syncSearchContexts.js";
 import { captureEvent } from "./posthog.js";
 import { PromClient } from "./promClient.js";
@@ -66,7 +66,7 @@ export class ConnectionManager {
 
     public startScheduler() {
         logger.debug('Starting scheduler');
-        this.interval = setInterval(async () => {
+        this.interval = setIntervalAsync(async () => {
             const thresholdDate = new Date(Date.now() - this.settings.resyncConnectionIntervalMs);
             const timeoutDate = new Date(Date.now() - JOB_TIMEOUT_MS);
 
diff --git a/packages/backend/src/ee/accountPermissionSyncer.ts b/packages/backend/src/ee/accountPermissionSyncer.ts
index eb32ba3b..81a1a135 100644
--- a/packages/backend/src/ee/accountPermissionSyncer.ts
+++ b/packages/backend/src/ee/accountPermissionSyncer.ts
@@ -7,6 +7,7 @@ import { PERMISSION_SYNC_SUPPORTED_CODE_HOST_TYPES } from "../constants.js";
 import { createOctokitFromToken, getReposForAuthenticatedUser } from "../github.js";
 import { createGitLabFromOAuthToken, getProjectsForAuthenticatedUser } from "../gitlab.js";
 import { Settings } from "../types.js";
+import { setIntervalAsync } from "../utils.js";
 
 const LOG_TAG = 'user-permission-syncer';
 const logger = createLogger(LOG_TAG);
@@ -46,7 +47,7 @@ export class AccountPermissionSyncer {
 
         logger.debug('Starting scheduler');
 
-        this.interval = setInterval(async () => {
+        this.interval = setIntervalAsync(async () => {
             const thresholdDate = new Date(Date.now() - this.settings.experiment_userDrivenPermissionSyncIntervalMs);
 
             const accounts = await this.db.account.findMany({
diff --git a/packages/backend/src/ee/repoPermissionSyncer.ts b/packages/backend/src/ee/repoPermissionSyncer.ts
index 078055ff..d48f510e 100644
--- a/packages/backend/src/ee/repoPermissionSyncer.ts
+++ b/packages/backend/src/ee/repoPermissionSyncer.ts
@@ -8,7 +8,7 @@ import { PERMISSION_SYNC_SUPPORTED_CODE_HOST_TYPES } from "../constants.js";
 import { createOctokitFromToken, getRepoCollaborators, GITHUB_CLOUD_HOSTNAME } from "../github.js";
 import { createGitLabFromPersonalAccessToken, getProjectMembers } from "../gitlab.js";
 import { Settings } from "../types.js";
-import { getAuthCredentialsForRepo } from "../utils.js";
+import { getAuthCredentialsForRepo, setIntervalAsync } from "../utils.js";
 
 type RepoPermissionSyncJob = {
     jobId: string;
@@ -48,7 +48,7 @@ export class RepoPermissionSyncer {
 
         logger.debug('Starting scheduler');
 
-        this.interval = setInterval(async () => {
+        this.interval = setIntervalAsync(async () => {
             // @todo: make this configurable
             const thresholdDate = new Date(Date.now() - this.settings.experiment_repoDrivenPermissionSyncIntervalMs);
 
diff --git a/packages/backend/src/repoIndexManager.ts b/packages/backend/src/repoIndexManager.ts
index cccc1b90..6be40d70 100644
--- a/packages/backend/src/repoIndexManager.ts
+++ b/packages/backend/src/repoIndexManager.ts
@@ -12,7 +12,7 @@ import { cloneRepository, fetchRepository, getBranches, getCommitHashForRefName,
 import { captureEvent } from './posthog.js';
 import { PromClient } from './promClient.js';
 import { RepoWithConnections, Settings } from "./types.js";
-import { getAuthCredentialsForRepo, getRepoPath, getShardPrefix, groupmqLifecycleExceptionWrapper, measure } from './utils.js';
+import { getAuthCredentialsForRepo, getRepoPath, getShardPrefix, groupmqLifecycleExceptionWrapper, measure, setIntervalAsync } from './utils.js';
 import { indexGitRepository } from './zoekt.js';
 
 const LOG_TAG = 'repo-index-manager';
@@ -72,9 +72,9 @@ export class RepoIndexManager {
         this.worker.on('error', this.onWorkerError.bind(this));
     }
 
-    public async startScheduler() {
+    public startScheduler() {
         logger.debug('Starting scheduler');
-        this.interval = setInterval(async () => {
+        this.interval = setIntervalAsync(async () => {
             await this.scheduleIndexJobs();
             await this.scheduleCleanupJobs();
         }, this.settings.reindexRepoPollingIntervalMs);
diff --git a/packages/backend/src/utils.ts b/packages/backend/src/utils.ts
index e85ce766..f41f32f3 100644
--- a/packages/backend/src/utils.ts
+++ b/packages/backend/src/utils.ts
@@ -268,3 +268,24 @@ export const groupmqLifecycleExceptionWrapper = async (name: string, logger: Log
     }
 }
 
+
+// setInterval wrapper that ensures async callbacks are not executed concurrently.
+// @see: https://mottaquikarim.github.io/dev/posts/setinterval-that-blocks-on-await/
+export const setIntervalAsync = (target: () => Promise<void>, pollingIntervalMs: number): NodeJS.Timeout => {
+    const setIntervalWithPromise = <T extends (...args: any[]) => Promise<any>>(
+        target: T
+    ): (...args: Parameters<T>) => Promise<void> => {
+        return async function (...args: Parameters<T>): Promise<void> {
+            if ((target as any).isRunning) return;
+    
+            (target as any).isRunning = true;
+            await target(...args);
+            (target as any).isRunning = false;
+        };
+    }
+
+    return setInterval(
+        setIntervalWithPromise(target),
+        pollingIntervalMs
+    );
+}
\ No newline at end of file