diff --git a/services/filestore/app/js/GcsPersistor.js b/services/filestore/app/js/GcsPersistor.js
index 799ee65905..ae1c2dd53a 100644
--- a/services/filestore/app/js/GcsPersistor.js
+++ b/services/filestore/app/js/GcsPersistor.js
@@ -65,17 +65,15 @@ async function sendFile(bucketName, key, fsPath) {
 
 async function sendStream(bucketName, key, readStream, sourceMd5) {
   try {
-    let hashPromise
+    // egress from us to gcs
+    const observeOptions = { metric: 'gcs.egress' }
 
-    // if there is no supplied md5 hash, we calculate the hash as the data passes through
     if (!sourceMd5) {
-      hashPromise = PersistorHelper.calculateStreamMd5(readStream)
+      // if there is no supplied md5 hash, we calculate the hash as the data passes through
+      observeOptions.hash = 'md5'
     }
 
-    const meteredStream = PersistorHelper.getMeteredStream(
-      readStream,
-      'gcs.egress' // egress from us to gcs
-    )
+    const observer = new PersistorHelper.ObserverStream(observeOptions)
 
     const writeOptions = {
       // disabling of resumable uploads is recommended by Google:
@@ -94,12 +92,12 @@ async function sendStream(bucketName, key, readStream, sourceMd5) {
       .file(key)
       .createWriteStream(writeOptions)
 
-    await pipeline(meteredStream, uploadStream)
+    await pipeline(readStream, observer, uploadStream)
 
     // if we didn't have an md5 hash, we should compare our computed one with Google's
     // as we couldn't tell GCS about it beforehand
-    if (hashPromise) {
-      sourceMd5 = await hashPromise
+    if (!sourceMd5) {
+      sourceMd5 = observer.getHash()
       // throws on mismatch
       await PersistorHelper.verifyMd5(GcsPersistor, bucketName, key, sourceMd5)
     }
@@ -124,14 +122,15 @@ async function getFileStream(bucketName, key, _opts = {}) {
     .file(key)
     .createReadStream(opts)
 
-  const meteredStream = PersistorHelper.getMeteredStream(
-    stream,
-    'gcs.ingress' // ingress to us from gcs
-  )
+  // ingress to us from gcs
+  const observer = new PersistorHelper.ObserverStream({
+    metric: 'gcs.ingress'
+  })
+  pipeline(stream, observer)
 
   try {
     await PersistorHelper.waitForStreamReady(stream)
-    return meteredStream
+    return observer
   } catch (err) {
     throw PersistorHelper.wrapError(
       err,
diff --git a/services/filestore/app/js/PersistorHelper.js b/services/filestore/app/js/PersistorHelper.js
index a58f024bb4..ad5152374f 100644
--- a/services/filestore/app/js/PersistorHelper.js
+++ b/services/filestore/app/js/PersistorHelper.js
@@ -1,17 +1,54 @@
 const crypto = require('crypto')
-const metrics = require('metrics-sharelatex')
-const meter = require('stream-meter')
 const Stream = require('stream')
 const logger = require('logger-sharelatex')
+const metrics = require('metrics-sharelatex')
 const { WriteError, ReadError, NotFoundError } = require('./Errors')
 const { promisify } = require('util')
 
 const pipeline = promisify(Stream.pipeline)
 
+// Observes data that passes through and computes some metadata for it
+// - specifically, it computes the number of bytes transferred, and optionally
+//   computes a cryptographic hash based on the 'hash' option. e.g., pass
+//   { hash: 'md5' } to compute the md5 hash of the stream
+// - if 'metric' is supplied as an option, this metric will be incremented by
+//   the number of bytes transferred
+class ObserverStream extends Stream.Transform {
+  constructor(options) {
+    super(options)
+
+    this.bytes = 0
+
+    if (options.hash) {
+      this.hash = crypto.createHash(options.hash)
+    }
+    if (options.metric) {
+      const onEnd = () => {
+        metrics.count(options.metric, this.bytes)
+      }
+      this.once('error', onEnd)
+      this.once('end', onEnd)
+    }
+  }
+
+  _transform(chunk, encoding, done) {
+    if (this.hash) {
+      this.hash.update(chunk)
+    }
+    this.bytes += chunk.length
+    this.push(chunk)
+    done()
+  }
+
+  getHash() {
+    return this.hash && this.hash.digest('hex')
+  }
+}
+
 module.exports = {
+  ObserverStream,
   calculateStreamMd5,
   verifyMd5,
-  getMeteredStream,
   waitForStreamReady,
   wrapError,
   hexToBase64,
@@ -19,6 +56,7 @@ module.exports = {
 }
 
 // returns a promise which resolves with the md5 hash of the stream
+// - consumes the stream
 function calculateStreamMd5(stream) {
   const hash = crypto.createHash('md5')
   hash.setEncoding('hex')
@@ -53,23 +91,6 @@ async function verifyMd5(persistor, bucket, key, sourceMd5, destMd5 = null) {
   }
 }
 
-// returns the next stream in the pipeline, and calls the callback with the byte count
-// when the stream finishes or receives an error
-function getMeteredStream(stream, metricName) {
-  const meteredStream = meter()
-
-  pipeline(stream, meteredStream)
-    .then(() => {
-      metrics.count(metricName, meteredStream.bytes)
-    })
-    .catch(() => {
-      // on error, just send how many bytes we received before the stream stopped
-      metrics.count(metricName, meteredStream.bytes)
-    })
-
-  return meteredStream
-}
-
 // resolves when a stream is 'readable', or rejects if the stream throws an error
 // before that happens - this lets us handle protocol-level errors before trying
 // to read them
diff --git a/services/filestore/app/js/S3Persistor.js b/services/filestore/app/js/S3Persistor.js
index 1b92a61ae6..ba82db31e2 100644
--- a/services/filestore/app/js/S3Persistor.js
+++ b/services/filestore/app/js/S3Persistor.js
@@ -10,13 +10,15 @@ const PersistorHelper = require('./PersistorHelper')
 const fs = require('fs')
 const S3 = require('aws-sdk/clients/s3')
 const { URL } = require('url')
-const { callbackify } = require('util')
+const Stream = require('stream')
+const { promisify, callbackify } = require('util')
 const {
   WriteError,
   ReadError,
   NotFoundError,
   SettingsError
 } = require('./Errors')
+const pipeline = promisify(Stream.pipeline)
 
 const S3Persistor = {
   sendFile: callbackify(sendFile),
@@ -51,26 +53,25 @@ async function sendFile(bucketName, key, fsPath) {
 
 async function sendStream(bucketName, key, readStream, sourceMd5) {
   try {
-    // if there is no supplied md5 hash, we calculate the hash as the data passes through
-    let hashPromise
+    // egress from us to S3
+    const observeOptions = { metric: 's3.egress' }
     let b64Hash
 
     if (sourceMd5) {
       b64Hash = PersistorHelper.hexToBase64(sourceMd5)
     } else {
-      hashPromise = PersistorHelper.calculateStreamMd5(readStream)
+      // if there is no supplied md5 hash, we calculate the hash as the data passes through
+      observeOptions.hash = 'md5'
     }
 
-    const meteredStream = PersistorHelper.getMeteredStream(
-      readStream,
-      's3.egress' // egress from us to s3
-    )
+    const observer = new PersistorHelper.ObserverStream(observeOptions)
+    pipeline(readStream, observer)
 
     // if we have an md5 hash, pass this to S3 to verify the upload
     const uploadOptions = {
       Bucket: bucketName,
       Key: key,
-      Body: meteredStream
+      Body: observer
     }
     if (b64Hash) {
       uploadOptions.ContentMD5 = b64Hash
@@ -92,8 +93,8 @@ async function sendStream(bucketName, key, readStream, sourceMd5) {
 
     // if we didn't have an md5 hash, we should compare our computed one with S3's
     // as we couldn't tell S3 about it beforehand
-    if (hashPromise) {
-      sourceMd5 = await hashPromise
+    if (!sourceMd5) {
+      sourceMd5 = observer.getHash()
       // throws on mismatch
       await PersistorHelper.verifyMd5(
         S3Persistor,
@@ -128,14 +129,13 @@ async function getFileStream(bucketName, key, opts) {
     .getObject(params)
     .createReadStream()
 
-  const meteredStream = PersistorHelper.getMeteredStream(
-    stream,
-    's3.ingress' // ingress to us from s3
-  )
+  // ingress from S3 to us
+  const observer = new PersistorHelper.ObserverStream({ metric: 's3.ingress' })
+  pipeline(stream, observer)
 
   try {
     await PersistorHelper.waitForStreamReady(stream)
-    return meteredStream
+    return observer
   } catch (err) {
     throw PersistorHelper.wrapError(
       err,
diff --git a/services/filestore/package-lock.json b/services/filestore/package-lock.json
index 90f5698668..f50ef5f552 100644
--- a/services/filestore/package-lock.json
+++ b/services/filestore/package-lock.json
@@ -5382,14 +5382,6 @@
         "stubs": "^3.0.0"
       }
     },
-    "stream-meter": {
-      "version": "1.0.4",
-      "resolved": "https://registry.npmjs.org/stream-meter/-/stream-meter-1.0.4.tgz",
-      "integrity": "sha512-4sOEtrbgFotXwnEuzzsQBYEV1elAeFSO8rSGeTwabuX1RRn/kEq9JVH7I0MRBhKVRR0sJkr0M0QCH7yOLf9fhQ==",
-      "requires": {
-        "readable-stream": "^2.1.4"
-      }
-    },
     "stream-shift": {
       "version": "1.0.1",
       "resolved": "https://registry.npmjs.org/stream-shift/-/stream-shift-1.0.1.tgz",
diff --git a/services/filestore/package.json b/services/filestore/package.json
index c4b8f16b15..53d7e24c6c 100644
--- a/services/filestore/package.json
+++ b/services/filestore/package.json
@@ -35,7 +35,6 @@
     "request-promise-native": "^1.0.8",
     "settings-sharelatex": "^1.1.0",
     "stream-buffers": "~0.2.5",
-    "stream-meter": "^1.0.4",
     "tiny-async-pool": "^1.1.0"
   },
   "devDependencies": {
diff --git a/services/filestore/test/unit/js/FSPersistorTests.js b/services/filestore/test/unit/js/FSPersistorTests.js
index 4777de502a..c8255987ba 100644
--- a/services/filestore/test/unit/js/FSPersistorTests.js
+++ b/services/filestore/test/unit/js/FSPersistorTests.js
@@ -3,6 +3,7 @@ const chai = require('chai')
 const { expect } = chai
 const SandboxedModule = require('sandboxed-module')
 const Errors = require('../../../app/js/Errors')
+const StreamModule = require('stream')
 
 chai.use(require('sinon-chai'))
 chai.use(require('chai-as-promised'))
@@ -38,7 +39,10 @@ describe('FSPersistorTests', function() {
       stat: sinon.stub().yields(null, stat)
     }
     glob = sinon.stub().yields(null, globs)
-    stream = { pipeline: sinon.stub().yields() }
+    stream = {
+      pipeline: sinon.stub().yields(),
+      Transform: StreamModule.Transform
+    }
     LocalFileWriter = {
       promises: {
         writeStream: sinon.stub().resolves(tempFile),
@@ -48,6 +52,7 @@ describe('FSPersistorTests', function() {
     Hash = {
       end: sinon.stub(),
       read: sinon.stub().returns(md5),
+      digest: sinon.stub().returns(md5),
       setEncoding: sinon.stub()
     }
     crypto = {
@@ -62,7 +67,6 @@ describe('FSPersistorTests', function() {
         stream,
         crypto,
         // imported by PersistorHelper but otherwise unused here
-        'stream-meter': {},
         'logger-sharelatex': {},
         'metrics-sharelatex': {}
       },
diff --git a/services/filestore/test/unit/js/GcsPersistorTests.js b/services/filestore/test/unit/js/GcsPersistorTests.js
index cd95bf1e20..0ca0f39d0f 100644
--- a/services/filestore/test/unit/js/GcsPersistorTests.js
+++ b/services/filestore/test/unit/js/GcsPersistorTests.js
@@ -5,6 +5,7 @@ const modulePath = '../../../app/js/GcsPersistor.js'
 const SandboxedModule = require('sandboxed-module')
 const { ObjectId } = require('mongodb')
 const asyncPool = require('tiny-async-pool')
+const StreamModule = require('stream')
 
 const Errors = require('../../../app/js/Errors')
 
@@ -13,7 +14,6 @@ describe('GcsPersistorTests', function() {
   const bucket = 'womBucket'
   const key = 'monKey'
   const destKey = 'donKey'
-  const objectSize = 5555
   const genericError = new Error('guru meditation error')
   const filesSize = 33
   const md5 = 'ffffffff00000000ffffffff00000000'
@@ -24,8 +24,6 @@ describe('GcsPersistorTests', function() {
     Storage,
     Fs,
     GcsNotFoundError,
-    Meter,
-    MeteredStream,
     ReadStream,
     Stream,
     GcsBucket,
@@ -71,7 +69,8 @@ describe('GcsPersistorTests', function() {
     }
 
     Stream = {
-      pipeline: sinon.stub().yields()
+      pipeline: sinon.stub().yields(),
+      Transform: StreamModule.Transform
     }
 
     Metrics = {
@@ -109,18 +108,10 @@ describe('GcsPersistorTests', function() {
     FileNotFoundError = new Error('File not found')
     FileNotFoundError.code = 'ENOENT'
 
-    MeteredStream = {
-      type: 'metered',
-      on: sinon.stub(),
-      bytes: objectSize
-    }
-    MeteredStream.on.withArgs('finish').yields()
-    MeteredStream.on.withArgs('readable').yields()
-    Meter = sinon.stub().returns(MeteredStream)
-
     Hash = {
       end: sinon.stub(),
       read: sinon.stub().returns(md5),
+      digest: sinon.stub().returns(md5),
       setEncoding: sinon.stub()
     }
     crypto = {
@@ -139,7 +130,6 @@ describe('GcsPersistorTests', function() {
         'tiny-async-pool': asyncPool,
         './Errors': Errors,
         fs: Fs,
-        'stream-meter': Meter,
         stream: Stream,
         'metrics-sharelatex': Metrics,
         crypto
@@ -157,7 +147,7 @@ describe('GcsPersistorTests', function() {
       })
 
       it('returns a metered stream', function() {
-        expect(stream).to.equal(MeteredStream)
+        expect(stream).to.be.instanceOf(StreamModule.Transform)
       })
 
       it('fetches the right key from the right bucket', function() {
@@ -169,13 +159,9 @@ describe('GcsPersistorTests', function() {
       it('pipes the stream through the meter', function() {
         expect(Stream.pipeline).to.have.been.calledWith(
           ReadStream,
-          MeteredStream
+          sinon.match.instanceOf(StreamModule.Transform)
         )
       })
-
-      it('records an ingress metric', function() {
-        expect(Metrics.count).to.have.been.calledWith('gcs.ingress', objectSize)
-      })
     })
 
     describe('when called with a byte range', function() {
@@ -189,7 +175,7 @@ describe('GcsPersistorTests', function() {
       })
 
       it('returns a metered stream', function() {
-        expect(stream).to.equal(MeteredStream)
+        expect(stream).to.be.instanceOf(StreamModule.Transform)
       })
 
       it('passes the byte range on to GCS', function() {
@@ -341,26 +327,16 @@ describe('GcsPersistorTests', function() {
         })
       })
 
-      it('should meter the stream', function() {
+      it('should meter the stream and pass it to GCS', function() {
         expect(Stream.pipeline).to.have.been.calledWith(
           ReadStream,
-          MeteredStream
-        )
-      })
-
-      it('should pipe the metered stream to GCS', function() {
-        expect(Stream.pipeline).to.have.been.calledWith(
-          MeteredStream,
+          sinon.match.instanceOf(StreamModule.Transform),
           WriteStream
         )
       })
 
-      it('should record an egress metric', function() {
-        expect(Metrics.count).to.have.been.calledWith('gcs.egress', objectSize)
-      })
-
       it('calculates the md5 hash of the file', function() {
-        expect(Stream.pipeline).to.have.been.calledWith(ReadStream, Hash)
+        expect(Hash.digest).to.have.been.called
       })
     })
 
@@ -375,10 +351,7 @@ describe('GcsPersistorTests', function() {
       })
 
       it('should not calculate the md5 hash of the file', function() {
-        expect(Stream.pipeline).not.to.have.been.calledWith(
-          sinon.match.any,
-          Hash
-        )
+        expect(Hash.digest).not.to.have.been.called
       })
 
       it('sends the hash in base64', function() {
@@ -400,7 +373,12 @@ describe('GcsPersistorTests', function() {
       let error
       beforeEach(async function() {
         Stream.pipeline
-          .withArgs(MeteredStream, WriteStream, sinon.match.any)
+          .withArgs(
+            ReadStream,
+            sinon.match.instanceOf(StreamModule.Transform),
+            WriteStream,
+            sinon.match.any
+          )
           .yields(genericError)
         try {
           await GcsPersistor.promises.sendStream(bucket, key, ReadStream)
@@ -438,10 +416,7 @@ describe('GcsPersistorTests', function() {
       it('should upload the stream via the meter', function() {
         expect(Stream.pipeline).to.have.been.calledWith(
           ReadStream,
-          MeteredStream
-        )
-        expect(Stream.pipeline).to.have.been.calledWith(
-          MeteredStream,
+          sinon.match.instanceOf(StreamModule.Transform),
           WriteStream
         )
       })
diff --git a/services/filestore/test/unit/js/S3PersistorTests.js b/services/filestore/test/unit/js/S3PersistorTests.js
index 484a0209a8..2117164d74 100644
--- a/services/filestore/test/unit/js/S3PersistorTests.js
+++ b/services/filestore/test/unit/js/S3PersistorTests.js
@@ -3,6 +3,7 @@ const chai = require('chai')
 const { expect } = chai
 const modulePath = '../../../app/js/S3Persistor.js'
 const SandboxedModule = require('sandboxed-module')
+const StreamModule = require('stream')
 
 const Errors = require('../../../app/js/Errors')
 
@@ -32,8 +33,6 @@ describe('S3PersistorTests', function() {
     Logger,
     S3,
     Fs,
-    Meter,
-    MeteredStream,
     ReadStream,
     Stream,
     S3Persistor,
@@ -63,7 +62,8 @@ describe('S3PersistorTests', function() {
     }
 
     Stream = {
-      pipeline: sinon.stub().yields()
+      pipeline: sinon.stub().yields(),
+      Transform: StreamModule.Transform
     }
 
     EmptyPromise = {
@@ -89,14 +89,6 @@ describe('S3PersistorTests', function() {
       createReadStream: sinon.stub().returns(ReadStream)
     }
 
-    MeteredStream = {
-      type: 'metered',
-      on: sinon.stub(),
-      bytes: objectSize
-    }
-    MeteredStream.on.withArgs('finish').yields()
-    Meter = sinon.stub().returns(MeteredStream)
-
     S3NotFoundError = new Error('not found')
     S3NotFoundError.code = 'NoSuchKey'
 
@@ -136,6 +128,7 @@ describe('S3PersistorTests', function() {
     Hash = {
       end: sinon.stub(),
       read: sinon.stub().returns(md5),
+      digest: sinon.stub().returns(md5),
       setEncoding: sinon.stub()
     }
     crypto = {
@@ -153,7 +146,6 @@ describe('S3PersistorTests', function() {
         'logger-sharelatex': Logger,
         './Errors': Errors,
         fs: Fs,
-        'stream-meter': Meter,
         stream: Stream,
         'metrics-sharelatex': Metrics,
         crypto
@@ -171,7 +163,7 @@ describe('S3PersistorTests', function() {
       })
 
       it('returns a metered stream', function() {
-        expect(stream).to.equal(MeteredStream)
+        expect(stream).to.be.instanceOf(StreamModule.Transform)
       })
 
       it('sets the AWS client up with credentials from settings', function() {
@@ -188,13 +180,9 @@ describe('S3PersistorTests', function() {
       it('pipes the stream through the meter', function() {
         expect(Stream.pipeline).to.have.been.calledWith(
           S3ReadStream,
-          MeteredStream
+          sinon.match.instanceOf(StreamModule.Transform)
         )
       })
-
-      it('records an ingress metric', function() {
-        expect(Metrics.count).to.have.been.calledWith('s3.ingress', objectSize)
-      })
     })
 
     describe('when called with a byte range', function() {
@@ -208,7 +196,7 @@ describe('S3PersistorTests', function() {
       })
 
       it('returns a metered stream', function() {
-        expect(stream).to.equal(MeteredStream)
+        expect(stream).to.be.instanceOf(Stream.Transform)
       })
 
       it('passes the byte range on to S3', function() {
@@ -242,7 +230,7 @@ describe('S3PersistorTests', function() {
       })
 
       it('returns a metered stream', function() {
-        expect(stream).to.equal(MeteredStream)
+        expect(stream).to.be.instanceOf(Stream.Transform)
       })
 
       it('sets the AWS client up with the alternative credentials', function() {
@@ -457,7 +445,7 @@ describe('S3PersistorTests', function() {
         expect(S3Client.upload).to.have.been.calledWith({
           Bucket: bucket,
           Key: key,
-          Body: MeteredStream
+          Body: sinon.match.instanceOf(Stream.Transform)
         })
       })
 
@@ -470,16 +458,12 @@ describe('S3PersistorTests', function() {
       it('should meter the stream', function() {
         expect(Stream.pipeline).to.have.been.calledWith(
           ReadStream,
-          MeteredStream
+          sinon.match.instanceOf(Stream.Transform)
         )
       })
 
-      it('should record an egress metric', function() {
-        expect(Metrics.count).to.have.been.calledWith('s3.egress', objectSize)
-      })
-
       it('calculates the md5 hash of the file', function() {
-        expect(Stream.pipeline).to.have.been.calledWith(ReadStream, Hash)
+        expect(Hash.digest).to.have.been.called
       })
     })
 
@@ -494,17 +478,14 @@ describe('S3PersistorTests', function() {
       })
 
       it('should not calculate the md5 hash of the file', function() {
-        expect(Stream.pipeline).not.to.have.been.calledWith(
-          sinon.match.any,
-          Hash
-        )
+        expect(Hash.digest).not.to.have.been.called
       })
 
       it('sends the hash in base64', function() {
         expect(S3Client.upload).to.have.been.calledWith({
           Bucket: bucket,
           Key: key,
-          Body: MeteredStream,
+          Body: sinon.match.instanceOf(StreamModule.Transform),
           ContentMD5: 'qqqqqru7u7uqqqqqu7u7uw=='
         })
       })
@@ -555,12 +536,12 @@ describe('S3PersistorTests', function() {
       it('should meter the download', function() {
         expect(Stream.pipeline).to.have.been.calledWith(
           S3ReadStream,
-          MeteredStream
+          sinon.match.instanceOf(Stream.Transform)
         )
       })
 
       it('should calculate the md5 hash from the file', function() {
-        expect(Stream.pipeline).to.have.been.calledWith(MeteredStream, Hash)
+        expect(Hash.digest).to.have.been.called
       })
     })
   })
@@ -579,7 +560,7 @@ describe('S3PersistorTests', function() {
         expect(S3Client.upload).to.have.been.calledWith({
           Bucket: bucket,
           Key: key,
-          Body: MeteredStream
+          Body: sinon.match.instanceOf(StreamModule.Transform)
         })
       })
     })