3 files changed, 43 insertions, 6 deletions
diff --git a/lib/util/cache/repository/types.ts b/lib/util/cache/repository/types.ts
index 3341418e230..f4798c8ab46 100644
--- a/lib/util/cache/repository/types.ts
+++ b/lib/util/cache/repository/types.ts
@@ -8,6 +8,7 @@ import type { RepoInitConfig } from '../../../workers/repository/init/types';
 import type { PrBlockedBy } from '../../../workers/types';
 
 export interface BaseBranchCache {
+  revision?: number;
   sha: string; // branch commit sha
   configHash: string; // object hash of config
   extractionFingerprints: Record<string, string | undefined>; // matching manager fingerprints
diff --git a/lib/workers/repository/process/extract-update.spec.ts b/lib/workers/repository/process/extract-update.spec.ts
index 21627e84b9c..220e9c8535e 100644
--- a/lib/workers/repository/process/extract-update.spec.ts
+++ b/lib/workers/repository/process/extract-update.spec.ts
@@ -6,7 +6,13 @@ import { fingerprint } from '../../../util/fingerprint';
 import type { LongCommitSha } from '../../../util/git/types';
 import { generateFingerprintConfig } from '../extract/extract-fingerprint-config';
 import * as _branchify from '../updates/branchify';
-import { extract, isCacheExtractValid, lookup, update } from './extract-update';
+import {
+  EXTRACT_CACHE_REVISION,
+  extract,
+  isCacheExtractValid,
+  lookup,
+  update,
+} from './extract-update';
 
 const createVulnerabilitiesMock = jest.fn();
 
@@ -97,6 +103,7 @@ describe('workers/repository/process/extract-update', () => {
       repositoryCache.getCache.mockReturnValueOnce({
         scan: {
           master: {
+            revision: EXTRACT_CACHE_REVISION,
             sha: '123test',
             configHash: fingerprint(generateFingerprintConfig(config)),
             extractionFingerprints: {},
@@ -150,6 +157,7 @@ describe('workers/repository/process/extract-update', () => {
 
     beforeEach(() => {
       cachedExtract = {
+        revision: EXTRACT_CACHE_REVISION,
         sha: 'sha',
         configHash: undefined as never,
         extractionFingerprints: {},
@@ -162,6 +170,18 @@ describe('workers/repository/process/extract-update', () => {
       expect(logger.logger.debug).toHaveBeenCalledTimes(0);
     });
 
+    it('returns false if no revision', () => {
+      delete cachedExtract.revision;
+      expect(isCacheExtractValid('sha', 'hash', cachedExtract)).toBe(false);
+      expect(logger.logger.debug).toHaveBeenCalledTimes(1);
+    });
+
+    it('returns false if revision mismatch', () => {
+      cachedExtract.revision = -1;
+      expect(isCacheExtractValid('sha', 'hash', cachedExtract)).toBe(false);
+      expect(logger.logger.debug).toHaveBeenCalledTimes(1);
+    });
+
     it('partial cache', () => {
       expect(isCacheExtractValid('sha', 'hash', cachedExtract)).toBe(false);
       expect(logger.logger.debug).toHaveBeenCalledTimes(0);
diff --git a/lib/workers/repository/process/extract-update.ts b/lib/workers/repository/process/extract-update.ts
index 75aecabd65a..610e519da73 100644
--- a/lib/workers/repository/process/extract-update.ts
+++ b/lib/workers/repository/process/extract-update.ts
@@ -18,6 +18,9 @@ import { Vulnerabilities } from './vulnerabilities';
 import type { WriteUpdateResult } from './write';
 import { writeUpdates } from './write';
 
+// Increment this if needing to cache bust ALL extract caches
+export const EXTRACT_CACHE_REVISION = 1;
+
 export interface ExtractResult {
   branches: BranchConfig[];
   branchList: string[];
@@ -69,7 +72,23 @@ export function isCacheExtractValid(
   configHash: string,
   cachedExtract?: BaseBranchCache,
 ): boolean {
-  if (!(cachedExtract?.sha && cachedExtract.configHash)) {
+  if (!cachedExtract) {
+    return false;
+  }
+
+  if (!cachedExtract.revision) {
+    logger.debug('Cached extract is missing revision, so cannot be used');
+    return false;
+  }
+
+  if (cachedExtract.revision !== EXTRACT_CACHE_REVISION) {
+    logger.debug(
+      `Extract cache revision has changed (old=${cachedExtract.revision}, new=${EXTRACT_CACHE_REVISION})`,
+    );
+    return false;
+  }
+
+  if (!(cachedExtract.sha && cachedExtract.configHash)) {
     return false;
   }
   if (cachedExtract.sha !== baseBranchSha) {
@@ -128,10 +147,6 @@ export async function extract(
         for (const file of files) {
           for (const dep of file.deps) {
             delete dep.updates;
-            if (dep.skipStage && dep.skipStage !== 'extract') {
-              delete dep.skipReason;
-              delete dep.skipStage;
-            }
           }
         }
       }
@@ -146,6 +161,7 @@ export async function extract(
     const { extractionFingerprints } = extractResult;
     // TODO: fix types (#22198)
     cache.scan[baseBranch!] = {
+      revision: EXTRACT_CACHE_REVISION,
       sha: baseBranchSha!,
       configHash,
       extractionFingerprints,