diff --git a/services/history-v1/config/default.json b/services/history-v1/config/default.json
index 74c5bcd237..c609730650 100644
--- a/services/history-v1/config/default.json
+++ b/services/history-v1/config/default.json
@@ -23,6 +23,7 @@
       }
     }
   },
+  "backupRPOInMS": "360000",
   "chunkStore": {
     "historyStoreConcurrency": "4"
   },
diff --git a/services/history-v1/storage/lib/backupVerifier.mjs b/services/history-v1/storage/lib/backupVerifier.mjs
index 55247b91d7..6e1bc3ee7b 100644
--- a/services/history-v1/storage/lib/backupVerifier.mjs
+++ b/services/history-v1/storage/lib/backupVerifier.mjs
@@ -1,16 +1,35 @@
 // @ts-check
 import config from 'config'
 import OError from '@overleaf/o-error'
-import { backupPersistor, projectBlobsBucket } from './backupPersistor.mjs'
-import { Blob } from 'overleaf-editor-core'
-import { BlobStore, makeProjectKey } from './blob_store/index.js'
+import chunkStore from '../lib/chunk_store/index.js'
+import {
+  backupPersistor,
+  chunksBucket,
+  projectBlobsBucket,
+} from './backupPersistor.mjs'
+import { Blob, Chunk, History } from 'overleaf-editor-core'
+import { BlobStore, GLOBAL_BLOBS, makeProjectKey } from './blob_store/index.js'
 import blobHash from './blob_hash.js'
 import { NotFoundError } from '@overleaf/object-persistor/src/Errors.js'
+import logger from '@overleaf/logger'
+import { text } from 'node:stream/consumers'
+import { createGunzip } from 'node:zlib'
+import path from 'node:path'
+import projectKey from './project_key.js'
+
+const RPO = parseInt(config.get('backupRPOInMS'), 10)
 
 /**
- * @typedef {import("@overleaf/object-persistor/src/PerProjectEncryptedS3Persistor").CachedPerProjectEncryptedS3Persistor} CachedPerProjectEncryptedS3Persistor
+ * @typedef {import("@overleaf/object-persistor/src/PerProjectEncryptedS3Persistor.js").CachedPerProjectEncryptedS3Persistor} CachedPerProjectEncryptedS3Persistor
  */
 
+/**
+ * @return {Date}
+ */
+export function getEndDateForRPO() {
+  return new Date(Date.now() - RPO)
+}
+
 /**
  * @param {string} historyId
  * @param {string} hash
@@ -20,13 +39,13 @@ export async function verifyBlob(historyId, hash) {
 }
 
 /**
+ *
  * @param {string} historyId
- * @param {Array<string>} hashes
+ * @return {Promise<CachedPerProjectEncryptedS3Persistor>}
  */
-export async function verifyBlobs(historyId, hashes) {
-  let projectCache
+async function getProjectPersistor(historyId) {
   try {
-    projectCache = await backupPersistor.forProjectRO(
+    return await backupPersistor.forProjectRO(
       projectBlobsBucket,
       makeProjectKey(historyId, '')
     )
@@ -36,16 +55,19 @@ export async function verifyBlobs(historyId, hashes) {
     }
     throw err
   }
-  await verifyBlobsWithCache(historyId, projectCache, hashes)
 }
 
 /**
  * @param {string} historyId
- * @param {CachedPerProjectEncryptedS3Persistor} projectCache
  * @param {Array<string>} hashes
+ * @param {CachedPerProjectEncryptedS3Persistor} [projectCache]
  */
-export async function verifyBlobsWithCache(historyId, projectCache, hashes) {
+export async function verifyBlobs(historyId, hashes, projectCache) {
   if (hashes.length === 0) throw new Error('bug: empty hashes')
+
+  if (!projectCache) {
+    projectCache = await getProjectPersistor(historyId)
+  }
   const blobStore = new BlobStore(historyId)
   for (const hash of hashes) {
     const path = makeProjectKey(historyId, hash)
@@ -58,7 +80,7 @@ export async function verifyBlobsWithCache(historyId, projectCache, hashes) {
       })
     } catch (err) {
       if (err instanceof NotFoundError) {
-        throw new BackupCorruptedError('missing blob')
+        throw new BackupCorruptedError('missing blob', { path, hash })
       }
       throw err
     }
@@ -73,7 +95,114 @@ export async function verifyBlobsWithCache(historyId, projectCache, hashes) {
   }
 }
 
+/**
+ * @param {string} historyId
+ * @param {Date} [endTimestamp]
+ */
+export async function verifyProjectWithErrorContext(
+  historyId,
+  endTimestamp = getEndDateForRPO()
+) {
+  try {
+    await verifyProject(historyId, endTimestamp)
+  } catch (err) {
+    // @ts-ignore err is Error instance
+    throw OError.tag(err, 'verifyProject', { historyId, endTimestamp })
+  }
+}
+
+/**
+ *
+ * @param {string} historyId
+ * @param {number} startVersion
+ * @param {CachedPerProjectEncryptedS3Persistor} backupPersistorForProject
+ * @return {Promise<any>}
+ */
+async function loadChunk(historyId, startVersion, backupPersistorForProject) {
+  const key = path.join(
+    projectKey.format(historyId),
+    projectKey.pad(startVersion)
+  )
+  const backupChunkStream = await backupPersistorForProject.getObjectStream(
+    chunksBucket,
+    key
+  )
+  const raw = await text(backupChunkStream.pipe(createGunzip()))
+  return JSON.parse(raw)
+}
+
+/**
+ * @param {string} historyId
+ * @param {Date} endTimestamp
+ */
+export async function verifyProject(historyId, endTimestamp) {
+  const backend = chunkStore.getBackend(historyId)
+  const [first, last] = await Promise.all([
+    backend.getFirstChunkBeforeTimestamp(historyId, endTimestamp),
+    backend.getLastActiveChunkBeforeTimestamp(historyId, endTimestamp),
+  ])
+
+  const chunksRecordsToVerify = [
+    {
+      chunkId: first.id,
+      chunkLabel: 'first',
+    },
+  ]
+  if (first.startVersion !== last.startVersion) {
+    chunksRecordsToVerify.push({
+      chunkId: last.id,
+      chunkLabel: 'last before RPO',
+    })
+  }
+
+  const projectCache = await getProjectPersistor(historyId)
+
+  const chunks = await Promise.all(
+    chunksRecordsToVerify.map(async chunk => {
+      try {
+        return History.fromRaw(
+          await loadChunk(historyId, chunk.startVersion, projectCache)
+        )
+      } catch (err) {
+        if (err instanceof Chunk.NotPersistedError) {
+          throw new BackupRPOViolationError('backup RPO violation', chunk)
+        }
+        throw err
+      }
+    })
+  )
+  const seenBlobs = new Set()
+  const blobsToVerify = []
+  for (const chunk of chunks) {
+    /** @type {Set<string>} */
+    const chunkBlobs = new Set()
+    chunk.findBlobHashes(chunkBlobs)
+    let hasAddedBlobFromThisChunk = false
+    for (const blobHash of chunkBlobs) {
+      if (seenBlobs.has(blobHash)) continue // old blob
+      if (GLOBAL_BLOBS.has(blobHash)) continue // global blob
+      seenBlobs.add(blobHash)
+      if (!hasAddedBlobFromThisChunk) {
+        blobsToVerify.push(blobHash)
+        hasAddedBlobFromThisChunk = true
+      }
+    }
+  }
+  if (blobsToVerify.length === 0) {
+    logger.debug(
+      {
+        historyId,
+        chunksRecordsToVerify: chunksRecordsToVerify.map(c => c.chunkId),
+      },
+      'chunks contain no blobs to verify'
+    )
+    return
+  }
+  await verifyBlobs(historyId, blobsToVerify, projectCache)
+}
+
 export class BackupCorruptedError extends OError {}
+export class BackupRPOViolationError extends OError {}
 
 export async function healthCheck() {
   /** @type {Array<string>} */
diff --git a/services/history-v1/storage/lib/chunk_store/mongo.js b/services/history-v1/storage/lib/chunk_store/mongo.js
index 6090c555bb..1c8e9f1b16 100644
--- a/services/history-v1/storage/lib/chunk_store/mongo.js
+++ b/services/history-v1/storage/lib/chunk_store/mongo.js
@@ -54,6 +54,35 @@ async function getChunkForVersion(projectId, version) {
   return chunkFromRecord(record)
 }
 
+/**
+ * Get the metadata for the chunk that contains the given version before the endTime.
+ */
+async function getFirstChunkBeforeTimestamp(projectId, timestamp) {
+  assert.mongoId(projectId, 'bad projectId')
+  assert.date(timestamp, 'bad timestamp')
+
+  const recordActive = await getChunkForVersion(projectId, 0)
+  if (recordActive && recordActive.endTimestamp <= timestamp) {
+    return recordActive
+  }
+
+  // fallback to deleted chunk
+  const recordDeleted = await mongodb.chunks.findOne(
+    {
+      projectId: new ObjectId(projectId),
+      state: 'deleted',
+      startVersion: 0,
+      updatedAt: { $lte: timestamp }, // indexed for state=deleted
+      endTimestamp: { $lte: timestamp },
+    },
+    { sort: { updatedAt: -1 } }
+  )
+  if (recordDeleted) {
+    return chunkFromRecord(recordDeleted)
+  }
+  throw new Chunk.BeforeTimestampNotFoundError(projectId, timestamp)
+}
+
 /**
  * Get the metadata for the chunk that contains the version that was current at
  * the given timestamp.
@@ -86,6 +115,39 @@ async function getChunkForTimestamp(projectId, timestamp) {
   return chunkFromRecord(record)
 }
 
+/**
+ * Get the metadata for the chunk that contains the version that was current before
+ * the given timestamp.
+ */
+async function getLastActiveChunkBeforeTimestamp(projectId, timestamp) {
+  assert.mongoId(projectId, 'bad projectId')
+  assert.date(timestamp, 'bad timestamp')
+
+  const record = await mongodb.chunks.findOne(
+    {
+      projectId: new ObjectId(projectId),
+      state: 'active',
+      $or: [
+        {
+          endTimestamp: {
+            $lte: timestamp,
+          },
+        },
+        {
+          endTimestamp: null,
+        },
+      ],
+    },
+    // We use the index on the startVersion for sorting records. This assumes
+    // that timestamps go up with each version.
+    { sort: { startVersion: -1 } }
+  )
+  if (record == null) {
+    throw new Chunk.BeforeTimestampNotFoundError(projectId, timestamp)
+  }
+  return chunkFromRecord(record)
+}
+
 /**
  * Get all of a project's chunk ids
  */
@@ -310,6 +372,8 @@ function chunkFromRecord(record) {
 
 module.exports = {
   getLatestChunk,
+  getFirstChunkBeforeTimestamp,
+  getLastActiveChunkBeforeTimestamp,
   getChunkForVersion,
   getChunkForTimestamp,
   getProjectChunkIds,
diff --git a/services/history-v1/storage/lib/chunk_store/postgres.js b/services/history-v1/storage/lib/chunk_store/postgres.js
index 072f1f1ce6..81df8e7021 100644
--- a/services/history-v1/storage/lib/chunk_store/postgres.js
+++ b/services/history-v1/storage/lib/chunk_store/postgres.js
@@ -46,6 +46,59 @@ async function getChunkForVersion(projectId, version) {
   return chunkFromRecord(record)
 }
 
+/**
+ * Get the metadata for the chunk that contains the given version.
+ */
+async function getFirstChunkBeforeTimestamp(projectId, timestamp) {
+  assert.date(timestamp, 'bad timestamp')
+
+  const recordActive = await getChunkForVersion(projectId, 0)
+  // projectId must be valid if getChunkForVersion did not throw
+  projectId = parseInt(projectId, 10)
+  if (recordActive && recordActive.endTimestamp <= timestamp) {
+    return recordActive
+  }
+
+  // fallback to deleted chunk
+  const recordDeleted = await knex('old_chunks')
+    .where('doc_id', projectId)
+    .where('start_version', '=', 0)
+    .where('end_timestamp', '<=', timestamp)
+    .orderBy('end_version', 'desc')
+    .first()
+  if (recordDeleted) {
+    return chunkFromRecord(recordDeleted)
+  }
+  throw new Chunk.BeforeTimestampNotFoundError(projectId, timestamp)
+}
+
+/**
+ * Get the metadata for the chunk that contains the version that was current at
+ * the given timestamp.
+ */
+async function getLastActiveChunkBeforeTimestamp(projectId, timestamp) {
+  assert.date(timestamp, 'bad timestamp')
+  assert.postgresId(projectId, 'bad projectId')
+  projectId = parseInt(projectId, 10)
+
+  const query = knex('chunks')
+    .where('doc_id', projectId)
+    .where(function () {
+      this.where('end_timestamp', '<=', timestamp).orWhere(
+        'end_timestamp',
+        null
+      )
+    })
+    .orderBy('end_version', 'desc', 'last')
+
+  const record = await query.first()
+
+  if (!record) {
+    throw new Chunk.BeforeTimestampNotFoundError(projectId, timestamp)
+  }
+  return chunkFromRecord(record)
+}
+
 /**
  * Get the metadata for the chunk that contains the version that was current at
  * the given timestamp.
@@ -280,6 +333,8 @@ async function generateProjectId() {
 
 module.exports = {
   getLatestChunk,
+  getFirstChunkBeforeTimestamp,
+  getLastActiveChunkBeforeTimestamp,
   getChunkForVersion,
   getChunkForTimestamp,
   getProjectChunkIds,
diff --git a/services/history-v1/storage/scripts/verify_project.mjs b/services/history-v1/storage/scripts/verify_project.mjs
new file mode 100644
index 0000000000..6e1cb9de89
--- /dev/null
+++ b/services/history-v1/storage/scripts/verify_project.mjs
@@ -0,0 +1,33 @@
+import commandLineArgs from 'command-line-args'
+import { verifyProjectWithErrorContext } from '../lib/backupVerifier.mjs'
+import knex from '../lib/knex.js'
+import { client } from '../lib/mongodb.js'
+import { setTimeout } from 'node:timers/promises'
+import { loadGlobalBlobs } from '../lib/blob_store/index.js'
+
+const { historyId } = commandLineArgs([{ name: 'historyId', type: String }])
+
+async function gracefulShutdown(code = process.exitCode) {
+  await knex.destroy()
+  await client.close()
+  await setTimeout(1_000)
+  process.exit(code)
+}
+
+if (!historyId) {
+  console.error('missing --historyId')
+  process.exitCode = 1
+  await gracefulShutdown()
+}
+
+await loadGlobalBlobs()
+
+try {
+  await verifyProjectWithErrorContext(historyId)
+  console.log('OK')
+} catch (error) {
+  console.error('error verifying', error)
+  process.exitCode = 1
+} finally {
+  await gracefulShutdown()
+}
diff --git a/services/history-v1/test/acceptance/js/api/backupVerifier.test.mjs b/services/history-v1/test/acceptance/js/api/backupVerifier.test.mjs
index 54a801a919..8b6836fab5 100644
--- a/services/history-v1/test/acceptance/js/api/backupVerifier.test.mjs
+++ b/services/history-v1/test/acceptance/js/api/backupVerifier.test.mjs
@@ -6,23 +6,63 @@ import { expect } from 'chai'
 import testProjects from './support/test_projects.js'
 import {
   backupPersistor,
+  chunksBucket,
   projectBlobsBucket,
 } from '../../../../storage/lib/backupPersistor.mjs'
 import {
   BlobStore,
   makeProjectKey,
 } from '../../../../storage/lib/blob_store/index.js'
-import Stream from 'stream'
+import Stream from 'node:stream'
 import * as zlib from 'node:zlib'
 import { promisify } from 'node:util'
 import { execFile } from 'node:child_process'
 import { NotFoundError } from '@overleaf/object-persistor/src/Errors.js'
+import { chunkStore } from '../../../../storage/index.js'
+import { Change, File, Operation } from 'overleaf-editor-core'
+import Crypto from 'node:crypto'
+import path from 'node:path'
+import projectKey from '../../../../storage/lib/project_key.js'
+import { historyStore } from '../../../../storage/lib/history_store.js'
 
 /**
  * @typedef {import("node-fetch").Response} Response
  * @typedef {import("overleaf-editor-core").Blob} Blob
  */
 
+async function verifyProjectScript(historyId) {
+  try {
+    const result = await promisify(execFile)(
+      process.argv0,
+      ['storage/scripts/verify_project.mjs', `--historyId=${historyId}`],
+      {
+        encoding: 'utf-8',
+        timeout: 5_000,
+        env: {
+          ...process.env,
+          LOG_LEVEL: 'warn',
+        },
+      }
+    )
+    return { status: 0, stdout: result.stdout, stderr: result.stderr }
+  } catch (err) {
+    if (
+      err &&
+      typeof err === 'object' &&
+      'stdout' in err &&
+      'code' in err &&
+      'stderr' in err
+    ) {
+      return {
+        stdout: typeof err.stdout === 'string' ? err.stdout : '',
+        status: typeof err.code === 'number' ? err.code : -1,
+        stderr: typeof err.stdout === 'string' ? err.stderr : '',
+      }
+    }
+    throw err
+  }
+}
+
 /**
  * @param {string} historyId
  * @param {string} hash
@@ -69,22 +109,84 @@ async function verifyBlobHTTP(historyId, hash) {
   )
 }
 
+async function backupChunk(historyId) {
+  const newChunk = await chunkStore.loadLatestRaw(historyId)
+  const { buffer: chunkBuffer } = await historyStore.loadRawWithBuffer(
+    historyId,
+    newChunk.id
+  )
+  const md5 = Crypto.createHash('md5').update(chunkBuffer)
+  await backupPersistor.sendStream(
+    chunksBucket,
+    path.join(
+      projectKey.format(historyId),
+      projectKey.pad(newChunk.startVersion)
+    ),
+    Stream.Readable.from([chunkBuffer]),
+    {
+      contentType: 'application/json',
+      contentEncoding: 'gzip',
+      contentLength: chunkBuffer.byteLength,
+      sourceMd5: md5.digest('hex'),
+    }
+  )
+}
+
+const FIFTEEN_MINUTES_IN_MS = 900_000
+
+async function addFileInNewChunk(
+  fileContents,
+  filePath,
+  historyId,
+  { creationDate = new Date() }
+) {
+  const chunk = await chunkStore.loadLatest(historyId)
+  const operation = Operation.addFile(
+    `${historyId}.txt`,
+    File.fromString(fileContents)
+  )
+  const changes = [new Change([operation], creationDate, [])]
+  chunk.pushChanges(changes)
+  await chunkStore.update(historyId, 0, chunk)
+}
+
 /**
  * @param {string} historyId
+ * @param {Object} [backup]
  * @return {Promise<string>}
  */
-async function prepareProjectAndBlob(historyId) {
+async function prepareProjectAndBlob(
+  historyId,
+  { shouldBackupBlob, shouldBackupChunk, shouldCreateChunk } = {
+    shouldBackupBlob: true,
+    shouldBackupChunk: true,
+    shouldCreateChunk: true,
+  }
+) {
   await testProjects.createEmptyProject(historyId)
   const blobStore = new BlobStore(historyId)
-  const blob = await blobStore.putString(historyId)
-  const gzipped = zlib.gzipSync(Buffer.from(historyId))
-  await backupPersistor.sendStream(
-    projectBlobsBucket,
-    makeProjectKey(historyId, blob.getHash()),
-    Stream.Readable.from([gzipped]),
-    { contentLength: gzipped.byteLength, contentEncoding: 'gzip' }
-  )
-  await checkDEKExists(historyId)
+  const fileContents = historyId
+  const blob = await blobStore.putString(fileContents)
+  if (shouldCreateChunk) {
+    await addFileInNewChunk(fileContents, `${historyId}.txt`, historyId, {
+      creationDate: new Date(new Date().getTime() - FIFTEEN_MINUTES_IN_MS),
+    })
+  }
+
+  if (shouldBackupBlob) {
+    const gzipped = zlib.gzipSync(Buffer.from(historyId))
+    await backupPersistor.sendStream(
+      projectBlobsBucket,
+      makeProjectKey(historyId, blob.getHash()),
+      Stream.Readable.from([gzipped]),
+      { contentLength: gzipped.byteLength, contentEncoding: 'gzip' }
+    )
+    await checkDEKExists(historyId)
+  }
+  if (shouldCreateChunk && shouldBackupChunk) {
+    await backupChunk(historyId)
+  }
+
   return blob.getHash()
 }
 
@@ -123,6 +225,53 @@ describe('backupVerifier', function () {
     const response = await fetch(testServer.testUrl('/health_check'))
     expect(response.status).to.equal(200)
   })
+  describe('storage/scripts/verify_project.mjs', function () {
+    describe('when the project is appropriately backed up', function () {
+      it('should return 0', async function () {
+        const response = await verifyProjectScript(historyIdPostgres)
+        expect(response.status).to.equal(0)
+      })
+    })
+    describe('when the project chunk is not backed up', function () {
+      let response
+      beforeEach(async function () {
+        await prepareProjectAndBlob('000000000000000000000043', {
+          shouldBackupChunk: false,
+          shouldBackupBlob: true,
+          shouldCreateChunk: true,
+        })
+        response = await verifyProjectScript('000000000000000000000043')
+      })
+      it('should return 1', async function () {
+        expect(response.status).to.equal(1)
+      })
+      it('should emit an error message referring to a missing chunk', async function () {
+        const stderr = response.stderr
+        expect(stderr).to.include('NotFoundError: no such file')
+        expect(stderr).to.include("bucketName: 'overleaf-test-history-chunks'")
+        expect(stderr).to.include("key: '340/000/000000000000000000/000000000'")
+      })
+    })
+    describe('when a project blob is not backed up', function () {
+      let response
+      beforeEach(async function () {
+        await prepareProjectAndBlob('43', {
+          shouldBackupChunk: true,
+          shouldBackupBlob: false,
+          shouldCreateChunk: true,
+        })
+        response = await verifyProjectScript('43')
+      })
+
+      it('should return 1', function () {
+        expect(response.status).to.equal(1)
+      })
+
+      it('includes a BackupCorruptedError in stderr', function () {
+        expect(response.stderr).to.include('BackupCorruptedError: missing blob')
+      })
+    })
+  })
   describe('storage/scripts/verify_backup_blob.mjs', function () {
     it('throws and does not create DEK if missing', async function () {
       const historyId = '404'