diff --git a/server/CloudflareAPI.js b/server/CloudflareAPI.js
index 8da56f9..d19ab92 100644
--- a/server/CloudflareAPI.js
+++ b/server/CloudflareAPI.js
@@ -22,10 +22,10 @@ function get(path, headers) {
 
 function getJSON(path, headers) {
   return get(path, headers)
-    .then(function(res) {
+    .then(res => {
       return res.json()
     })
-    .then(function(data) {
+    .then(data => {
       if (!data.success) {
         console.error(`CloudflareAPI.getJSON failed at ${path}`)
         console.error(data)
@@ -38,11 +38,11 @@ function getJSON(path, headers) {
 
 function getZones(domains) {
   return Promise.all(
-    (Array.isArray(domains) ? domains : [domains]).map(function(domain) {
+    (Array.isArray(domains) ? domains : [domains]).map(domain => {
       return getJSON(`/zones?name=${domain}`)
     })
-  ).then(function(results) {
-    return results.reduce(function(memo, zones) {
+  ).then(results => {
+    return results.reduce((memo, zones) => {
       return memo.concat(zones)
     })
   })
@@ -64,14 +64,14 @@ function reduceResults(target, values) {
 
 function getZoneAnalyticsDashboard(zones, since, until) {
   return Promise.all(
-    (Array.isArray(zones) ? zones : [zones]).map(function(zone) {
+    (Array.isArray(zones) ? zones : [zones]).map(zone => {
       return getJSON(
         `/zones/${
           zone.id
         }/analytics/dashboard?since=${since.toISOString()}&until=${until.toISOString()}`
       )
     })
-  ).then(function(results) {
+  ).then(results => {
     return results.reduce(reduceResults)
   })
 }
@@ -82,10 +82,10 @@ function getJSONStream(path, headers) {
   })
 
   return get(path, acceptGzipHeaders)
-    .then(function(res) {
+    .then(res => {
       return res.body.pipe(gunzip())
     })
-    .then(function(stream) {
+    .then(stream => {
       return stream.pipe(ndjson.parse())
     })
 }
diff --git a/server/StatsServer.js b/server/StatsServer.js
index 2712a2c..6a0cc23 100644
--- a/server/StatsServer.js
+++ b/server/StatsServer.js
@@ -4,7 +4,7 @@ const db = require('./RedisClient')
 const PackageBlacklist = require('./PackageBlacklist').blacklist
 
 function prunePackages(packagesMap) {
-  PackageBlacklist.forEach(function(packageName) {
+  PackageBlacklist.forEach(packageName => {
     delete packagesMap[packageName]
   })
 
@@ -26,15 +26,16 @@ function createMinuteKey(date) {
 function createScoresMap(array) {
   const map = {}
 
-  for (let i = 0; i < array.length; i += 2)
+  for (let i = 0; i < array.length; i += 2) {
     map[array[i]] = parseInt(array[i + 1], 10)
+  }
 
   return map
 }
 
 function getScoresMap(key, n = 100) {
-  return new Promise(function(resolve, reject) {
-    db.zrevrange(key, 0, n, 'withscores', function(error, value) {
+  return new Promise((resolve, reject) => {
+    db.zrevrange(key, 0, n, 'withscores', (error, value) => {
       if (error) {
         reject(error)
       } else {
@@ -67,7 +68,7 @@ function addDailyMetricsToTimeseries(timeseries) {
     getPackageRequests(since),
     getPackageBandwidth(since),
     getProtocolRequests(since)
-  ]).then(function(results) {
+  ]).then(results => {
     timeseries.requests.package = results[0]
     timeseries.bandwidth.package = results[1]
     timeseries.requests.protocol = results[2]
@@ -76,8 +77,8 @@ function addDailyMetricsToTimeseries(timeseries) {
 }
 
 function sumMaps(maps) {
-  return maps.reduce(function(memo, map) {
-    Object.keys(map).forEach(function(key) {
+  return maps.reduce((memo, map) => {
+    Object.keys(map).forEach(key => {
       memo[key] = (memo[key] || 0) + map[key]
     })
 
@@ -87,23 +88,19 @@ function sumMaps(maps) {
 
 function addDailyMetrics(result) {
   return Promise.all(result.timeseries.map(addDailyMetricsToTimeseries)).then(
-    function() {
+    () => {
       result.totals.requests.package = sumMaps(
-        result.timeseries.map(function(timeseries) {
+        result.timeseries.map(timeseries => {
           return timeseries.requests.package
         })
       )
 
       result.totals.bandwidth.package = sumMaps(
-        result.timeseries.map(function(timeseries) {
-          return timeseries.bandwidth.package
-        })
+        result.timeseries.map(timeseries => timeseries.bandwidth.package)
       )
 
       result.totals.requests.protocol = sumMaps(
-        result.timeseries.map(function(timeseries) {
-          return timeseries.requests.protocol
-        })
+        result.timeseries.map(timeseries => timeseries.requests.protocol)
       )
 
       return result
@@ -143,15 +140,13 @@ function extractPublicInfo(data) {
 const DomainNames = ['unpkg.com', 'npmcdn.com']
 
 function fetchStats(since, until) {
-  return cf.getZones(DomainNames).then(function(zones) {
-    return cf
-      .getZoneAnalyticsDashboard(zones, since, until)
-      .then(function(dashboard) {
-        return {
-          timeseries: dashboard.timeseries.map(extractPublicInfo),
-          totals: extractPublicInfo(dashboard.totals)
-        }
-      })
+  return cf.getZones(DomainNames).then(zones => {
+    return cf.getZoneAnalyticsDashboard(zones, since, until).then(dashboard => {
+      return {
+        timeseries: dashboard.timeseries.map(extractPublicInfo),
+        totals: extractPublicInfo(dashboard.totals)
+      }
+    })
   })
 }
 
@@ -164,7 +159,7 @@ function getStats(since, until, callback) {
 
   if (until - since > oneDay) promise = promise.then(addDailyMetrics)
 
-  promise.then(function(value) {
+  promise.then(value => {
     callback(null, value)
   }, callback)
 }
diff --git a/server/createServer.test.js b/server/createServer.test.js
index bc25306..34a145b 100644
--- a/server/createServer.test.js
+++ b/server/createServer.test.js
@@ -3,14 +3,14 @@ const createServer = require('./createServer')
 
 describe('The server app', function() {
   let app
-  beforeEach(function() {
+  beforeEach(() => {
     app = createServer()
   })
 
   it('rejects invalid package names', function(done) {
     request(app)
       .get('/_invalid/index.js')
-      .then(function(res) {
+      .then(res => {
         expect(res.statusCode).toBe(403)
         done()
       })
@@ -19,7 +19,7 @@ describe('The server app', function() {
   it('redirects invalid query params', function(done) {
     request(app)
       .get('/react?main=index&invalid')
-      .then(function(res) {
+      .then(res => {
         expect(res.statusCode).toBe(302)
         expect(res.headers.location).toBe('/react?main=index')
         done()
@@ -29,7 +29,7 @@ describe('The server app', function() {
   it('redirects /_meta to ?meta', function(done) {
     request(app)
       .get('/_meta/react?main=index')
-      .then(function(res) {
+      .then(res => {
         expect(res.statusCode).toBe(302)
         expect(res.headers.location).toBe('/react?main=index&meta')
         done()
diff --git a/server/ingestLogs.js b/server/ingestLogs.js
index 1697230..309a215 100644
--- a/server/ingestLogs.js
+++ b/server/ingestLogs.js
@@ -37,7 +37,7 @@ const oneMinute = oneSecond * 60
 const oneHour = oneMinute * 60
 
 function computeCounters(stream) {
-  return new Promise(function(resolve, reject) {
+  return new Promise((resolve, reject) => {
     const counters = {}
     const expireat = {}
 
@@ -113,11 +113,11 @@ function computeCounters(stream) {
 }
 
 function processLogs(stream) {
-  return computeCounters(stream).then(function({ counters, expireat }) {
-    Object.keys(counters).forEach(function(key) {
+  return computeCounters(stream).then(({ counters, expireat }) => {
+    Object.keys(counters).forEach(key => {
       const values = counters[key]
 
-      Object.keys(values).forEach(function(member) {
+      Object.keys(values).forEach(member => {
         db.zincrby(key, values[member], member)
       })
 
@@ -127,7 +127,7 @@ function processLogs(stream) {
 }
 
 function ingestLogs(zone, startSeconds, endSeconds) {
-  return new Promise(function(resolve) {
+  return new Promise(resolve => {
     console.log(
       'info: Started ingesting logs for %s from %s to %s',
       zone.name,
@@ -138,7 +138,7 @@ function ingestLogs(zone, startSeconds, endSeconds) {
     const startFetchTime = Date.now()
 
     resolve(
-      cf.getLogs(zone.id, startSeconds, endSeconds).then(function(stream) {
+      cf.getLogs(zone.id, startSeconds, endSeconds).then(stream => {
         const endFetchTime = Date.now()
 
         console.log(
@@ -150,7 +150,7 @@ function ingestLogs(zone, startSeconds, endSeconds) {
 
         const startProcessTime = Date.now()
 
-        return processLogs(stream).then(function() {
+        return processLogs(stream).then(() => {
           const endProcessTime = Date.now()
 
           console.log(
@@ -226,8 +226,8 @@ function startZone(zone) {
   takeATurn()
 }
 
-Promise.all(DomainNames.map(cf.getZones)).then(function(results) {
-  const zones = results.reduce(function(memo, zones) {
+Promise.all(DomainNames.map(cf.getZones)).then(results => {
+  const zones = results.reduce((memo, zones) => {
     return memo.concat(zones)
   })
 
diff --git a/server/middleware/fetchFile.js b/server/middleware/fetchFile.js
index 8077bff..acd93ec 100644
--- a/server/middleware/fetchFile.js
+++ b/server/middleware/fetchFile.js
@@ -20,7 +20,7 @@ const FindExtensions = ['', '.js', '.json']
  * depending on which one is available, similar to require('lib/file').
  */
 function findFile(base, useIndex, callback) {
-  FindExtensions.reduceRight(function(next, ext) {
+  FindExtensions.reduceRight((next, ext) => {
     const file = base + ext
 
     return function() {
diff --git a/server/middleware/packageURL.js b/server/middleware/packageURL.js
index 1ee7e2f..7bb6a03 100644
--- a/server/middleware/packageURL.js
+++ b/server/middleware/packageURL.js
@@ -19,7 +19,7 @@ function queryIsKnown(query) {
 function sanitizeQuery(query) {
   const saneQuery = {}
 
-  Object.keys(query).forEach(function(param) {
+  Object.keys(query).forEach(param => {
     if (isKnownQueryParam(param)) saneQuery[param] = query[param]
   })
 
diff --git a/server/middleware/utils/createMutex.js b/server/middleware/utils/createMutex.js
index da5f666..5a08e33 100644
--- a/server/middleware/utils/createMutex.js
+++ b/server/middleware/utils/createMutex.js
@@ -13,7 +13,7 @@ function createMutex(doWork) {
       ]
 
       doWork(payload, function(error, value) {
-        mutex[key].forEach(function(callback) {
+        mutex[key].forEach(callback => {
           callback(error, value)
         })
       })
diff --git a/server/middleware/utils/createSearch.js b/server/middleware/utils/createSearch.js
index 65a4b17..5985af3 100644
--- a/server/middleware/utils/createSearch.js
+++ b/server/middleware/utils/createSearch.js
@@ -1,7 +1,7 @@
 function createSearch(query) {
   const params = []
 
-  Object.keys(query).forEach(function(param) {
+  Object.keys(query).forEach(param => {
     if (query[param] === '') {
       params.push(param) // Omit the trailing "=" from param=
     } else {
diff --git a/server/middleware/utils/getIndexHTML.js b/server/middleware/utils/getIndexHTML.js
index 651d1b1..701f5ff 100644
--- a/server/middleware/utils/getIndexHTML.js
+++ b/server/middleware/utils/getIndexHTML.js
@@ -8,7 +8,7 @@ const IndexPage = require('../components/IndexPage')
 const e = React.createElement
 
 function getEntries(dir) {
-  return new Promise(function(resolve, reject) {
+  return new Promise((resolve, reject) => {
     fs.readdir(dir, function(error, files) {
       if (error) {
         reject(error)
@@ -16,8 +16,8 @@ function getEntries(dir) {
         resolve(
           Promise.all(
             files.map(file => getFileStats(path.join(dir, file)))
-          ).then(function(statsArray) {
-            return statsArray.map(function(stats, index) {
+          ).then(statsArray => {
+            return statsArray.map((stats, index) => {
               return { file: files[index], stats }
             })
           })
diff --git a/server/middleware/utils/getMetadata.js b/server/middleware/utils/getMetadata.js
index 7768e19..d93176b 100644
--- a/server/middleware/utils/getMetadata.js
+++ b/server/middleware/utils/getMetadata.js
@@ -6,26 +6,24 @@ const getFileStats = require('./getFileStats')
 const getFileType = require('./getFileType')
 
 function getEntries(dir, file, maximumDepth) {
-  return new Promise(function(resolve, reject) {
+  return new Promise((resolve, reject) => {
     fs.readdir(path.join(dir, file), function(error, files) {
       if (error) {
         reject(error)
       } else {
         resolve(
           Promise.all(
-            files.map(function(f) {
-              return getFileStats(path.join(dir, file, f))
-            })
-          ).then(function(statsArray) {
+            files.map(f => getFileStats(path.join(dir, file, f)))
+          ).then(statsArray => {
             return Promise.all(
-              statsArray.map(function(stats, index) {
-                return getMetadataRecursive(
+              statsArray.map((stats, index) =>
+                getMetadataRecursive(
                   dir,
                   path.join(file, files[index]),
                   stats,
                   maximumDepth - 1
                 )
-              })
+              )
             )
           })
         )
@@ -39,7 +37,7 @@ function formatTime(time) {
 }
 
 function getIntegrity(file) {
-  return new Promise(function(resolve, reject) {
+  return new Promise((resolve, reject) => {
     fs.readFile(file, function(error, data) {
       if (error) {
         reject(error)
@@ -60,7 +58,7 @@ function getMetadataRecursive(dir, file, stats, maximumDepth) {
   }
 
   if (stats.isFile()) {
-    return getIntegrity(path.join(dir, file)).then(function(integrity) {
+    return getIntegrity(path.join(dir, file)).then(integrity => {
       metadata.integrity = integrity
       return metadata
     })
@@ -69,7 +67,7 @@ function getMetadataRecursive(dir, file, stats, maximumDepth) {
   if (!stats.isDirectory() || maximumDepth === 0)
     return Promise.resolve(metadata)
 
-  return getEntries(dir, file, maximumDepth).then(function(files) {
+  return getEntries(dir, file, maximumDepth).then(files => {
     metadata.files = files
     return metadata
   })
diff --git a/server/middleware/utils/getPackage.js b/server/middleware/utils/getPackage.js
index 85fc1fa..c2a0eb9 100644
--- a/server/middleware/utils/getPackage.js
+++ b/server/middleware/utils/getPackage.js
@@ -26,7 +26,7 @@ function ignoreSymlinks(file, headers) {
 }
 
 function extractResponse(response, outputDir) {
-  return new Promise(function(resolve, reject) {
+  return new Promise((resolve, reject) => {
     const extract = tar.extract(outputDir, {
       readable: true, // All dirs/files should be readable.
       map: stripNamePrefix,
@@ -44,12 +44,12 @@ function extractResponse(response, outputDir) {
 function fetchAndExtract(tarballURL, outputDir) {
   console.log(`info: Fetching ${tarballURL} and extracting to ${outputDir}`)
 
-  return fetch(tarballURL).then(function(response) {
+  return fetch(tarballURL).then(response => {
     return extractResponse(response, outputDir)
   })
 }
 
-const fetchMutex = createMutex(function(payload, callback) {
+const fetchMutex = createMutex((payload, callback) => {
   const { tarballURL, outputDir } = payload
 
   fs.access(outputDir, function(error) {
@@ -61,7 +61,7 @@ const fetchMutex = createMutex(function(payload, callback) {
           if (error) {
             callback(error)
           } else {
-            fetchAndExtract(tarballURL, outputDir).then(function() {
+            fetchAndExtract(tarballURL, outputDir).then(() => {
               callback()
             }, callback)
           }
diff --git a/server/middleware/utils/getPackageInfo.js b/server/middleware/utils/getPackageInfo.js
index 3cac869..87ec5b8 100644
--- a/server/middleware/utils/getPackageInfo.js
+++ b/server/middleware/utils/getPackageInfo.js
@@ -22,7 +22,7 @@ function fetchPackageInfo(packageName) {
     headers: {
       Accept: 'application/json'
     }
-  }).then(function(res) {
+  }).then(res => {
     return res.status === 404 ? null : res.json()
   })
 }
@@ -31,7 +31,7 @@ const PackageNotFound = 'PackageNotFound'
 
 // This mutex prevents multiple concurrent requests to
 // the registry for the same package info.
-const fetchMutex = createMutex(function(packageName, callback) {
+const fetchMutex = createMutex((packageName, callback) => {
   fetchPackageInfo(packageName).then(
     function(value) {
       if (value == null) {
diff --git a/server/npm/getAssetPaths.js b/server/npm/getAssetPaths.js
index 0ae9535..86d1e12 100644
--- a/server/npm/getAssetPaths.js
+++ b/server/npm/getAssetPaths.js
@@ -5,7 +5,7 @@ function getAssetPaths(packageName, version) {
   const entries = assetPathsIndex[packageName]
 
   if (entries) {
-    const matchingEntry = entries.find(function(entry) {
+    const matchingEntry = entries.find(entry => {
       const range = entry[0]
 
       if (range == null || semver.satisfies(version, range)) return entry
diff --git a/server/npm/search.js b/server/npm/search.js
index 1220d50..db89a52 100644
--- a/server/npm/search.js
+++ b/server/npm/search.js
@@ -2,15 +2,15 @@ const searchIndex = require('./searchIndex')
 const getAssetPaths = require('./getAssetPaths')
 
 function enhanceHit(hit) {
-  return new Promise(function(resolve, reject) {
+  return new Promise((resolve, reject) => {
     const assetPaths = getAssetPaths(hit.name, hit.version)
 
     if (assetPaths) {
       // TODO: Double check the package metadata to ensure the files
       // haven't moved from the paths in the index?
-      hit.assets = assetPaths.map(function(path) {
-        return `https://unpkg.com/${hit.name}@${hit.version}${path}`
-      })
+      hit.assets = assetPaths.map(
+        path => `https://unpkg.com/${hit.name}@${hit.version}${path}`
+      )
 
       resolve(hit)
     } else {
@@ -30,7 +30,7 @@ function concat(string) {
 }
 
 function search(query, page) {
-  return new Promise(function(resolve, reject) {
+  return new Promise((resolve, reject) => {
     const hitsPerPage = 10
 
     const params = {
@@ -61,7 +61,7 @@ function search(query, page) {
         reject(error)
       } else {
         resolve(
-          Promise.all(value.hits.map(enhanceHit)).then(function(hits) {
+          Promise.all(value.hits.map(enhanceHit)).then(hits => {
             const totalHits = value.nbHits
             const totalPages = value.nbPages