diff --git a/AUTHORS.md b/AUTHORS.md
index 3d185d1f..0f21e9a1 100644
--- a/AUTHORS.md
+++ b/AUTHORS.md
@@ -43,5 +43,8 @@
 - crapthings (crapthings@gmail.com)
 - daiyu (qqdaiyu55@gmail.com)
 - LI (kslrwang@gmail.com)
+- Jimmy Wärting (jimmy@warting.se)
+- Justin Kalland (justin@kalland.ch)
+- greenkeeper[bot] (23040076+greenkeeper[bot]@users.noreply.github.com)
 
 #### Generated by tools/update-authors.sh.
diff --git a/client.js b/client.js
index a49bde53..9560fe48 100644
--- a/client.js
+++ b/client.js
@@ -1,11 +1,9 @@
-const { Buffer } = require('safe-buffer')
 const debug = require('debug')('bittorrent-tracker:client')
 const EventEmitter = require('events')
 const once = require('once')
 const parallel = require('run-parallel')
 const Peer = require('simple-peer')
 const uniq = require('uniq')
-const url = require('url')
 
 const common = require('./lib/common')
 const HTTPTracker = require('./lib/client/http-tracker') // empty object in browser
@@ -62,7 +60,7 @@ class Client extends EventEmitter {
     this._wrtc = typeof opts.wrtc === 'function' ? opts.wrtc() : opts.wrtc
 
     let announce = typeof opts.announce === 'string'
-      ? [ opts.announce ]
+      ? [opts.announce]
       : opts.announce == null ? [] : opts.announce
 
     // Remove trailing slash from trackers to catch duplicates
@@ -85,7 +83,14 @@ class Client extends EventEmitter {
 
     this._trackers = announce
       .map(announceUrl => {
-        const parsedUrl = url.parse(announceUrl)
+        let parsedUrl
+        try {
+          parsedUrl = new URL(announceUrl)
+        } catch (err) {
+          nextTickWarn(new Error(`Invalid tracker URL: ${announceUrl}`))
+          return null
+        }
+
         const port = parsedUrl.port
         if (port < 0 || port > 65535) {
           nextTickWarn(new Error(`Invalid tracker port: ${announceUrl}`))
diff --git a/lib/client/udp-tracker.js b/lib/client/udp-tracker.js
index 56e1b8a7..24a30800 100644
--- a/lib/client/udp-tracker.js
+++ b/lib/client/udp-tracker.js
@@ -1,11 +1,9 @@
 const arrayRemove = require('unordered-array-remove')
 const BN = require('bn.js')
-const Buffer = require('safe-buffer').Buffer
 const compact2string = require('compact2string')
 const debug = require('debug')('bittorrent-tracker:udp-tracker')
 const dgram = require('dgram')
 const randombytes = require('randombytes')
-const url = require('url')
 
 const common = require('../common')
 const Tracker = require('./tracker')
@@ -73,7 +71,7 @@ class UDPTracker extends Tracker {
   _request (opts) {
     const self = this
     if (!opts) opts = {}
-    const parsedUrl = url.parse(this.announceUrl)
+    const parsedUrl = new URL(this.announceUrl)
     let transactionId = genTransactionId()
     let socket = dgram.createSocket('udp4')
 
@@ -176,7 +174,7 @@ class UDPTracker extends Tracker {
           }
           const infoHashes = (Array.isArray(opts.infoHash) && opts.infoHash.length > 0)
             ? opts.infoHash.map(infoHash => { return infoHash.toString('hex') })
-            : [ (opts.infoHash && opts.infoHash.toString('hex')) || self.client.infoHash ]
+            : [(opts.infoHash && opts.infoHash.toString('hex')) || self.client.infoHash]
 
           for (let i = 0, len = (msg.length - 8) / 12; i < len; i += 1) {
             self.client.emit('scrape', {
diff --git a/lib/common-node.js b/lib/common-node.js
index b06d0004..7a9e87d6 100644
--- a/lib/common-node.js
+++ b/lib/common-node.js
@@ -3,14 +3,13 @@
  * These are separate from common.js so they can be skipped when bundling for the browser.
  */
 
-var Buffer = require('safe-buffer').Buffer
 var querystring = require('querystring')
 
 exports.IPV4_RE = /^[\d.]+$/
 exports.IPV6_RE = /^[\da-fA-F:]+$/
 exports.REMOVE_IPV4_MAPPED_IPV6_RE = /^::ffff:/
 
-exports.CONNECTION_ID = Buffer.concat([ toUInt32(0x417), toUInt32(0x27101980) ])
+exports.CONNECTION_ID = Buffer.concat([toUInt32(0x417), toUInt32(0x27101980)])
 exports.ACTIONS = { CONNECT: 0, ANNOUNCE: 1, SCRAPE: 2, ERROR: 3 }
 exports.EVENTS = { update: 0, completed: 1, started: 2, stopped: 3 }
 exports.EVENT_IDS = {
diff --git a/lib/common.js b/lib/common.js
index 90d12f55..f735a856 100644
--- a/lib/common.js
+++ b/lib/common.js
@@ -2,8 +2,6 @@
  * Functions/constants needed by both the client and server.
  */
 
-var Buffer = require('safe-buffer').Buffer
-
 exports.DEFAULT_ANNOUNCE_PEERS = 50
 exports.MAX_ANNOUNCE_PEERS = 82
 
diff --git a/lib/server/parse-http.js b/lib/server/parse-http.js
index bf6cb2c4..85a1c872 100644
--- a/lib/server/parse-http.js
+++ b/lib/server/parse-http.js
@@ -42,7 +42,7 @@ function parseHttpRequest (req, opts) {
   } else if (opts.action === 'scrape' || s[0] === '/scrape') {
     params.action = common.ACTIONS.SCRAPE
 
-    if (typeof params.info_hash === 'string') params.info_hash = [ params.info_hash ]
+    if (typeof params.info_hash === 'string') params.info_hash = [params.info_hash]
     if (Array.isArray(params.info_hash)) {
       params.info_hash = params.info_hash.map(function (binaryInfoHash) {
         if (typeof binaryInfoHash !== 'string' || binaryInfoHash.length !== 20) {
diff --git a/lib/server/parse-websocket.js b/lib/server/parse-websocket.js
index ec4e606d..4416008a 100644
--- a/lib/server/parse-websocket.js
+++ b/lib/server/parse-websocket.js
@@ -39,7 +39,7 @@ function parseWebSocketRequest (socket, opts, params) {
   } else if (params.action === 'scrape') {
     params.action = common.ACTIONS.SCRAPE
 
-    if (typeof params.info_hash === 'string') params.info_hash = [ params.info_hash ]
+    if (typeof params.info_hash === 'string') params.info_hash = [params.info_hash]
     if (Array.isArray(params.info_hash)) {
       params.info_hash = params.info_hash.map(function (binaryInfoHash) {
         if (typeof binaryInfoHash !== 'string' || binaryInfoHash.length !== 20) {
diff --git a/package.json b/package.json
index d7ad198d..bd55af19 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "bittorrent-tracker",
   "description": "Simple, robust, BitTorrent tracker (client & server) implementation",
-  "version": "9.11.0",
+  "version": "9.13.0",
   "author": {
     "name": "WebTorrent, LLC",
     "email": "feross@webtorrent.io",
@@ -19,7 +19,7 @@
   "dependencies": {
     "bencode": "^2.0.0",
     "bittorrent-peerid": "^1.0.2",
-    "bn.js": "^4.4.0",
+    "bn.js": "^5.0.0",
     "compact2string": "^1.2.0",
     "debug": "^4.0.1",
     "ip": "^1.0.1",
@@ -30,14 +30,13 @@
     "randombytes": "^2.0.3",
     "run-parallel": "^1.1.2",
     "run-series": "^1.0.2",
-    "safe-buffer": "^5.0.0",
     "simple-get": "^3.0.0",
     "simple-peer": "^9.0.0",
-    "simple-websocket": "^7.0.1",
+    "simple-websocket": "^8.0.0",
     "string2compact": "^1.1.1",
     "uniq": "^1.0.1",
     "unordered-array-remove": "^1.0.2",
-    "ws": "^6.0.0"
+    "ws": "^7.0.0"
   },
   "devDependencies": {
     "electron-webrtc": "^0.3.0",
@@ -46,9 +45,8 @@
     "tape": "^4.0.0",
     "webtorrent-fixtures": "^1.3.0"
   },
-  "optionalDependencies": {
-    "bufferutil": "^4.0.0",
-    "utf-8-validate": "^5.0.1"
+  "engines": {
+    "node": ">=10"
   },
   "keywords": [
     "bittorrent",
@@ -62,12 +60,16 @@
   ],
   "license": "MIT",
   "main": "index.js",
+  "optionalDependencies": {
+    "bufferutil": "^4.0.0",
+    "utf-8-validate": "^5.0.1"
+  },
   "repository": {
     "type": "git",
     "url": "git://github.com/webtorrent/bittorrent-tracker.git"
   },
   "scripts": {
-    "update-authors": "./tools/update-authors.sh",
-    "test": "standard && tape test/*.js"
+    "test": "standard && tape test/*.js",
+    "update-authors": "./tools/update-authors.sh"
   }
 }
diff --git a/server.js b/server.js
index 10eb8393..80f5cf52 100644
--- a/server.js
+++ b/server.js
@@ -1,4 +1,3 @@
-const { Buffer } = require('safe-buffer')
 const bencode = require('bencode')
 const debug = require('debug')('bittorrent-tracker:server')
 const dgram = require('dgram')
@@ -15,6 +14,8 @@ const parseHttpRequest = require('./lib/server/parse-http')
 const parseUdpRequest = require('./lib/server/parse-udp')
 const parseWebSocketRequest = require('./lib/server/parse-websocket')
 
+const hasOwnProperty = Object.prototype.hasOwnProperty
+
 /**
  * BitTorrent tracker server.
  *
@@ -147,7 +148,7 @@ class Server extends EventEmitter {
           let key
 
           for (key in allPeers) {
-            if (allPeers.hasOwnProperty(key) && filterFunction(allPeers[key])) {
+            if (hasOwnProperty.call(allPeers, key) && filterFunction(allPeers[key])) {
               count++
             }
           }
@@ -158,7 +159,7 @@ class Server extends EventEmitter {
         function groupByClient () {
           const clients = {}
           for (const key in allPeers) {
-            if (allPeers.hasOwnProperty(key)) {
+            if (hasOwnProperty.call(allPeers, key)) {
               const peer = allPeers[key]
 
               if (!clients[peer.client.client]) {
@@ -179,10 +180,10 @@ class Server extends EventEmitter {
         function printClients (clients) {
           let html = '<ul>\n'
           for (const name in clients) {
-            if (clients.hasOwnProperty(name)) {
+            if (hasOwnProperty.call(clients, name)) {
               const client = clients[name]
               for (const version in client) {
-                if (client.hasOwnProperty(version)) {
+                if (hasOwnProperty.call(client, version)) {
                   html += `<li><strong>${name}</strong> ${version} : ${client[version]}</li>\n`
                 }
               }
@@ -203,7 +204,7 @@ class Server extends EventEmitter {
               const peer = peers.peek(peerId)
               if (peer == null) return // peers.peek() can evict the peer
 
-              if (!allPeers.hasOwnProperty(peerId)) {
+              if (!hasOwnProperty.call(allPeers, peerId)) {
                 allPeers[peerId] = {
                   ipv4: false,
                   ipv6: false,
@@ -247,7 +248,7 @@ class Server extends EventEmitter {
             clients: groupByClient()
           }
 
-          if (req.url === '/stats.json' || req.headers['accept'] === 'application/json') {
+          if (req.url === '/stats.json' || req.headers.accept === 'application/json') {
             res.write(JSON.stringify(stats))
             res.end()
           } else if (req.url === '/stats') {
diff --git a/test/client-large-torrent.js b/test/client-large-torrent.js
index 7f9f2497..00a62c21 100644
--- a/test/client-large-torrent.js
+++ b/test/client-large-torrent.js
@@ -1,4 +1,3 @@
-var Buffer = require('safe-buffer').Buffer
 var Client = require('../')
 var common = require('./common')
 var fixtures = require('webtorrent-fixtures')
diff --git a/test/client-magnet.js b/test/client-magnet.js
index ba1949c9..bb768eab 100644
--- a/test/client-magnet.js
+++ b/test/client-magnet.js
@@ -1,4 +1,3 @@
-var Buffer = require('safe-buffer').Buffer
 var Client = require('../')
 var common = require('./common')
 var fixtures = require('webtorrent-fixtures')
diff --git a/test/client-ws-socket-pool.js b/test/client-ws-socket-pool.js
index 94f6b2dd..a87619f9 100644
--- a/test/client-ws-socket-pool.js
+++ b/test/client-ws-socket-pool.js
@@ -1,4 +1,3 @@
-var Buffer = require('safe-buffer').Buffer
 var Client = require('../')
 var common = require('./common')
 var fixtures = require('webtorrent-fixtures')
diff --git a/test/client.js b/test/client.js
index 1d38986b..e622c1ab 100644
--- a/test/client.js
+++ b/test/client.js
@@ -1,4 +1,3 @@
-var Buffer = require('safe-buffer').Buffer
 var Client = require('../')
 var common = require('./common')
 var fixtures = require('webtorrent-fixtures')
@@ -357,7 +356,7 @@ function testClientAnnounceWithNumWant (t, serverType) {
   common.createServer(t, serverType, function (server, announceUrl) {
     var client1 = new Client({
       infoHash: fixtures.leaves.parsedTorrent.infoHash,
-      announce: [ announceUrl ],
+      announce: [announceUrl],
       peerId: peerId1,
       port: port,
       wrtc: {}
diff --git a/test/destroy.js b/test/destroy.js
index f6eafb64..5437b8ac 100644
--- a/test/destroy.js
+++ b/test/destroy.js
@@ -1,4 +1,3 @@
-var Buffer = require('safe-buffer').Buffer
 var Client = require('../')
 var common = require('./common')
 var fixtures = require('webtorrent-fixtures')
diff --git a/test/evict.js b/test/evict.js
index 1ff60bbb..605b03bf 100644
--- a/test/evict.js
+++ b/test/evict.js
@@ -1,4 +1,3 @@
-var Buffer = require('safe-buffer').Buffer
 var Client = require('../')
 var common = require('./common')
 var test = require('tape')
@@ -31,7 +30,7 @@ function serverTest (t, serverType, serverFamily) {
 
     var client1 = new Client({
       infoHash: infoHash,
-      announce: [ announceUrl ],
+      announce: [announceUrl],
       peerId: peerId,
       port: 6881,
       wrtc: wrtc
@@ -43,7 +42,7 @@ function serverTest (t, serverType, serverFamily) {
     client1.once('update', function (data) {
       var client2 = new Client({
         infoHash: infoHash,
-        announce: [ announceUrl ],
+        announce: [announceUrl],
         peerId: peerId2,
         port: 6882,
         wrtc: wrtc
@@ -68,7 +67,7 @@ function serverTest (t, serverType, serverFamily) {
 
           var client3 = new Client({
             infoHash: infoHash,
-            announce: [ announceUrl ],
+            announce: [announceUrl],
             peerId: peerId3,
             port: 6880,
             wrtc: wrtc
diff --git a/test/filter.js b/test/filter.js
index 8eb4dd80..395e2336 100644
--- a/test/filter.js
+++ b/test/filter.js
@@ -1,4 +1,3 @@
-var Buffer = require('safe-buffer').Buffer
 var Client = require('../')
 var common = require('./common')
 var fixtures = require('webtorrent-fixtures')
diff --git a/test/querystring.js b/test/querystring.js
index e20ddfad..217e3624 100644
--- a/test/querystring.js
+++ b/test/querystring.js
@@ -1,4 +1,3 @@
-var Buffer = require('safe-buffer').Buffer
 var common = require('../lib/common')
 var test = require('tape')
 
diff --git a/test/request-handler.js b/test/request-handler.js
index e04e6651..d825a31e 100644
--- a/test/request-handler.js
+++ b/test/request-handler.js
@@ -1,4 +1,3 @@
-var Buffer = require('safe-buffer').Buffer
 var Client = require('../')
 var common = require('./common')
 var fixtures = require('webtorrent-fixtures')
diff --git a/test/scrape.js b/test/scrape.js
index 6391449b..b372ec2d 100644
--- a/test/scrape.js
+++ b/test/scrape.js
@@ -1,5 +1,4 @@
 var bencode = require('bencode')
-var Buffer = require('safe-buffer').Buffer
 var Client = require('../')
 var common = require('./common')
 var commonLib = require('../lib/common')
@@ -119,7 +118,7 @@ function clientScrapeMulti (t, serverType) {
 
   commonTest.createServer(t, serverType, function (server, announceUrl) {
     Client.scrape({
-      infoHash: [ infoHash1, infoHash2 ],
+      infoHash: [infoHash1, infoHash2],
       announce: announceUrl
     }, function (err, results) {
       t.error(err)
@@ -161,7 +160,7 @@ test('server: multiple info_hash scrape (manual http request)', function (t) {
     var scrapeUrl = announceUrl.replace('/announce', '/scrape')
 
     var url = scrapeUrl + '?' + commonLib.querystringStringify({
-      info_hash: [ binaryInfoHash1, binaryInfoHash2 ]
+      info_hash: [binaryInfoHash1, binaryInfoHash2]
     })
 
     get.concat(url, function (err, res, data) {
diff --git a/test/server.js b/test/server.js
index 73e9fe66..1c611bc2 100644
--- a/test/server.js
+++ b/test/server.js
@@ -1,4 +1,3 @@
-var Buffer = require('safe-buffer').Buffer
 var Client = require('../')
 var common = require('./common')
 var test = require('tape')
@@ -33,7 +32,7 @@ function serverTest (t, serverType, serverFamily) {
 
     var client1 = new Client({
       infoHash: infoHash,
-      announce: [ announceUrl ],
+      announce: [announceUrl],
       peerId: peerId,
       port: 6881,
       wrtc: wrtc
@@ -93,7 +92,7 @@ function serverTest (t, serverType, serverFamily) {
 
             var client2 = new Client({
               infoHash: infoHash,
-              announce: [ announceUrl ],
+              announce: [announceUrl],
               peerId: peerId2,
               port: 6882,
               wrtc: wrtc
@@ -113,7 +112,7 @@ function serverTest (t, serverType, serverFamily) {
 
               var client3 = new Client({
                 infoHash: infoHash,
-                announce: [ announceUrl ],
+                announce: [announceUrl],
                 peerId: peerId3,
                 port: 6880,
                 wrtc: wrtc
diff --git a/test/stats.js b/test/stats.js
index 15d0c0f5..5b14f81b 100644
--- a/test/stats.js
+++ b/test/stats.js
@@ -1,4 +1,3 @@
-var Buffer = require('safe-buffer').Buffer
 var Client = require('../')
 var commonTest = require('./common')
 var fixtures = require('webtorrent-fixtures')
@@ -145,7 +144,7 @@ test('server: get leecher stats.json', function (t) {
         t.equal(stats.peersSeederOnly, 0)
         t.equal(stats.peersLeecherOnly, 1)
         t.equal(stats.peersSeederAndLeecher, 0)
-        t.equal(stats.clients['WebTorrent']['0.91'], 1)
+        t.equal(stats.clients.WebTorrent['0.91'], 1)
 
         client.destroy(function () { t.pass('client destroyed') })
         server.close(function () { t.pass('server closed') })
@@ -186,7 +185,7 @@ test('server: get leecher stats.json (unknown peerId)', function (t) {
         t.equal(stats.peersSeederOnly, 0)
         t.equal(stats.peersLeecherOnly, 1)
         t.equal(stats.peersSeederAndLeecher, 0)
-        t.equal(stats.clients['unknown']['01234567'], 1)
+        t.equal(stats.clients.unknown['01234567'], 1)
 
         client.destroy(function () { t.pass('client destroyed') })
         server.close(function () { t.pass('server closed') })