diff --git a/packages/das/src/queue/constants.ts b/packages/das/src/queue/constants.ts
index 04046ea..730f994 100644
--- a/packages/das/src/queue/constants.ts
+++ b/packages/das/src/queue/constants.ts
@@ -5,10 +5,16 @@ export const FETCH_JOBS = {
   PR_FILES: "fetch-pr-files",
   BACKFILL_REPO: "backfill-repo",
   ISSUE_CLOSURE: "fetch-issue-closure",
+  RECONCILE_REGISTRY: "reconcile-registry",
 } as const;
 
 export const DEFAULT_BACKFILL_DAYS = 40;
 
+export const REGISTRY_RECONCILE_CRON = "0 */2 * * *";
+
+export const MASTER_REPOSITORIES_URL =
+  "https://raw.githubusercontent.com/entrius/gittensor/test/gittensor/validator/weights/master_repositories.json";
+
 export function prFilesJobId(
   repoFullName: string,
   prNumber: number,
diff --git a/packages/das/src/queue/fetch.processor.ts b/packages/das/src/queue/fetch.processor.ts
index 08e1e6d..48c32c1 100644
--- a/packages/das/src/queue/fetch.processor.ts
+++ b/packages/das/src/queue/fetch.processor.ts
@@ -5,6 +5,7 @@ import { IsNull, Repository } from "typeorm";
 import { Job, Queue } from "bullmq";
 import { Issue, PullRequest } from "../entities";
 import { GitHubFetcherService } from "../webhook/github-fetcher.service";
+import { RegistryReconcilerService } from "./registry-reconciler.service";
 import {
   FETCH_QUEUE,
   FETCH_JOBS,
@@ -57,6 +58,7 @@ export class FetchProcessor extends WorkerHost {
     private readonly issueRepo: Repository<Issue>,
     @InjectQueue(FETCH_QUEUE)
     private readonly fetchQueue: Queue,
+    private readonly registryReconciler: RegistryReconcilerService,
   ) {
     super();
   }
@@ -82,6 +84,10 @@ export class FetchProcessor extends WorkerHost {
         await this.handleIssueClosure(repoFullName, issueNumber);
         break;
       }
+      case FETCH_JOBS.RECONCILE_REGISTRY: {
+        await this.registryReconciler.reconcile();
+        break;
+      }
       default:
         this.logger.warn(`Unknown job name: ${job.name}`);
     }
diff --git a/packages/das/src/queue/queue.module.ts b/packages/das/src/queue/queue.module.ts
index 1fcd6d9..c0b91c9 100644
--- a/packages/das/src/queue/queue.module.ts
+++ b/packages/das/src/queue/queue.module.ts
@@ -13,6 +13,7 @@ import {
 } from "../entities";
 import { GitHubFetcherService } from "../webhook/github-fetcher.service";
 import { FetchProcessor } from "./fetch.processor";
+import { RegistryReconcilerService } from "./registry-reconciler.service";
 import { FETCH_QUEUE } from "./constants";
 
 @Module({
@@ -38,7 +39,7 @@ import { FETCH_QUEUE } from "./constants";
       Review,
     ]),
   ],
-  providers: [FetchProcessor, GitHubFetcherService],
+  providers: [FetchProcessor, GitHubFetcherService, RegistryReconcilerService],
   exports: [BullModule],
 })
 export class QueueModule {}
diff --git a/packages/das/src/queue/registry-reconciler.service.ts b/packages/das/src/queue/registry-reconciler.service.ts
new file mode 100644
index 0000000..e1c31d8
--- /dev/null
+++ b/packages/das/src/queue/registry-reconciler.service.ts
@@ -0,0 +1,82 @@
+import { Injectable, Logger, OnModuleInit } from "@nestjs/common";
+import { InjectQueue } from "@nestjs/bullmq";
+import { InjectRepository } from "@nestjs/typeorm";
+import { Queue } from "bullmq";
+import { In, Repository } from "typeorm";
+import { Repo } from "../entities";
+import {
+  FETCH_JOBS,
+  FETCH_QUEUE,
+  MASTER_REPOSITORIES_URL,
+  REGISTRY_RECONCILE_CRON,
+} from "./constants";
+
+@Injectable()
+export class RegistryReconcilerService implements OnModuleInit {
+  private readonly logger = new Logger(RegistryReconcilerService.name);
+
+  constructor(
+    @InjectQueue(FETCH_QUEUE) private readonly fetchQueue: Queue,
+    @InjectRepository(Repo) private readonly repoRepo: Repository<Repo>,
+  ) {}
+
+  async onModuleInit(): Promise<void> {
+    // BullMQ deduplicates repeatable jobs by repeat key, so restarts
+    // don't accumulate duplicate schedules.
+    await this.fetchQueue.add(
+      FETCH_JOBS.RECONCILE_REGISTRY,
+      {},
+      {
+        repeat: { pattern: REGISTRY_RECONCILE_CRON },
+        removeOnComplete: true,
+        removeOnFail: 50,
+      },
+    );
+  }
+
+  async reconcile(): Promise<void> {
+    const canonical = await this.fetchCanonicalRepos();
+    // Fail-safe: a network blip or non-200 must never mass-deregister.
+    if (!canonical) return;
+    if (canonical.size === 0) {
+      this.logger.warn("Canonical repo list is empty — refusing to deregister");
+      return;
+    }
+
+    const registered = await this.repoRepo.find({
+      select: ["repoFullName"],
+      where: { registered: true },
+    });
+    const toDeregister = registered
+      .map((r) => r.repoFullName)
+      .filter((name) => !canonical.has(name.toLowerCase()));
+
+    // installationId stays — delisting != uninstalling; re-list via admin/repos/register.
+    await this.repoRepo.update(
+      { repoFullName: In(toDeregister) },
+      { registered: false },
+    );
+
+    this.logger.log(
+      `Registry reconcile: deregistered ${toDeregister.length} repo(s)` +
+        (toDeregister.length ? `: ${toDeregister.join(", ")}` : ""),
+    );
+  }
+
+  private async fetchCanonicalRepos(): Promise<Set<string> | null> {
+    try {
+      const res = await fetch(MASTER_REPOSITORIES_URL);
+      if (!res.ok) {
+        this.logger.error(
+          `Master repos fetch returned ${res.status} ${res.statusText}`,
+        );
+        return null;
+      }
+      const json = (await res.json()) as Record<string, unknown>;
+      return new Set(Object.keys(json).map((k) => k.toLowerCase()));
+    } catch (err) {
+      this.logger.error(`Master repos fetch failed: ${String(err)}`);
+      return null;
+    }
+  }
+}