diff --git a/Makefile b/Makefile
index d638304c7a2784..e526ad5242d519 100644
--- a/Makefile
+++ b/Makefile
@@ -513,8 +513,8 @@ bench-idle:
 	$(NODE) benchmark/idle_clients.js &
 
 jslint:
-	$(NODE) tools/eslint/bin/eslint.js lib src test tools/doc tools/eslint-rules \
-		--rulesdir tools/eslint-rules
+	$(NODE) tools/eslint/bin/eslint.js benchmark lib src test tools/doc \
+	  tools/eslint-rules --rulesdir tools/eslint-rules
 
 CPPLINT_EXCLUDE ?=
 CPPLINT_EXCLUDE += src/node_lttng.cc
diff --git a/benchmark/arrays/var-int.js b/benchmark/arrays/var-int.js
index 47a7e62dc7681b..74a73c9515fffa 100644
--- a/benchmark/arrays/var-int.js
+++ b/benchmark/arrays/var-int.js
@@ -1,6 +1,9 @@
+'use strict';
 var common = require('../common.js');
 var bench = common.createBenchmark(main, {
-  type: 'Array Buffer Int8Array Uint8Array Int16Array Uint16Array Int32Array Uint32Array Float32Array Float64Array'.split(' '),
+  type: ['Array', 'Buffer', 'Int8Array', 'Uint8Array', 'Int16Array',
+         'Uint16Array', 'Int32Array', 'Uint32Array', 'Float32Array',
+         'Float64Array'],
   n: [25]
 });
 
diff --git a/benchmark/arrays/zero-float.js b/benchmark/arrays/zero-float.js
index a6624205bffdea..e2569eed5c4e75 100644
--- a/benchmark/arrays/zero-float.js
+++ b/benchmark/arrays/zero-float.js
@@ -1,6 +1,9 @@
+'use strict';
 var common = require('../common.js');
 var bench = common.createBenchmark(main, {
-  type: 'Array Buffer Int8Array Uint8Array Int16Array Uint16Array Int32Array Uint32Array Float32Array Float64Array'.split(' '),
+  type: ['Array', 'Buffer', 'Int8Array', 'Uint8Array', 'Int16Array',
+         'Uint16Array', 'Int32Array', 'Uint32Array', 'Float32Array',
+         'Float64Array'],
   n: [25]
 });
 
diff --git a/benchmark/arrays/zero-int.js b/benchmark/arrays/zero-int.js
index 29a2d58b665cbe..8be70c1e87113a 100644
--- a/benchmark/arrays/zero-int.js
+++ b/benchmark/arrays/zero-int.js
@@ -1,6 +1,9 @@
+'use strict';
 var common = require('../common.js');
 var bench = common.createBenchmark(main, {
-  type: 'Array Buffer Int8Array Uint8Array Int16Array Uint16Array Int32Array Uint32Array Float32Array Float64Array'.split(' '),
+  type: ['Array', 'Buffer', 'Int8Array', 'Uint8Array', 'Int16Array',
+         'Uint16Array', 'Int32Array', 'Uint32Array', 'Float32Array',
+         'Float64Array'],
   n: [25]
 });
 
diff --git a/benchmark/buffers/buffer-base64-decode.js b/benchmark/buffers/buffer-base64-decode.js
index 23ab92462f8927..36094f632d4eec 100644
--- a/benchmark/buffers/buffer-base64-decode.js
+++ b/benchmark/buffers/buffer-base64-decode.js
@@ -1,3 +1,4 @@
+'use strict';
 const assert = require('assert');
 const common = require('../common.js');
 
diff --git a/benchmark/buffers/buffer-base64-encode.js b/benchmark/buffers/buffer-base64-encode.js
index cb520be2a621eb..8e2eec3cf5bb37 100644
--- a/benchmark/buffers/buffer-base64-encode.js
+++ b/benchmark/buffers/buffer-base64-encode.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 
 var bench = common.createBenchmark(main, {});
@@ -6,9 +7,10 @@ function main(conf) {
   var N = 64 * 1024 * 1024;
   var b = Buffer(N);
   var s = '';
-  for (var i = 0; i < 256; ++i) s += String.fromCharCode(i);
-  for (var i = 0; i < N; i += 256) b.write(s, i, 256, 'ascii');
+  var i;
+  for (i = 0; i < 256; ++i) s += String.fromCharCode(i);
+  for (i = 0; i < N; i += 256) b.write(s, i, 256, 'ascii');
   bench.start();
-  for (var i = 0; i < 32; ++i) b.toString('base64');
+  for (i = 0; i < 32; ++i) b.toString('base64');
   bench.end(64);
 }
diff --git a/benchmark/buffers/buffer-bytelength.js b/benchmark/buffers/buffer-bytelength.js
index 6a7afe6921aea1..50f420f412d30b 100644
--- a/benchmark/buffers/buffer-bytelength.js
+++ b/benchmark/buffers/buffer-bytelength.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common');
 
 var bench = common.createBenchmark(main, {
@@ -43,7 +44,7 @@ function main(conf) {
     var r = Buffer.byteLength(strings[index], encoding);
 
     if (r !== results[index])
-      throw Error('incorrect return value');
+      throw new Error('incorrect return value');
   }
   bench.end(n);
 }
diff --git a/benchmark/buffers/buffer-compare.js b/benchmark/buffers/buffer-compare.js
index b02e8a74030042..c83bb67fa24ad8 100644
--- a/benchmark/buffers/buffer-compare.js
+++ b/benchmark/buffers/buffer-compare.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 
 var bench = common.createBenchmark(main, {
diff --git a/benchmark/buffers/buffer-creation.js b/benchmark/buffers/buffer-creation.js
index bc0c55711858de..dfb68467cc54b9 100644
--- a/benchmark/buffers/buffer-creation.js
+++ b/benchmark/buffers/buffer-creation.js
@@ -1,4 +1,5 @@
-SlowBuffer = require('buffer').SlowBuffer;
+'use strict';
+const SlowBuffer = require('buffer').SlowBuffer;
 
 var common = require('../common.js');
 var bench = common.createBenchmark(main, {
@@ -13,7 +14,7 @@ function main(conf) {
   var clazz = conf.type === 'fast' ? Buffer : SlowBuffer;
   bench.start();
   for (var i = 0; i < n * 1024; i++) {
-    b = new clazz(len);
+    new clazz(len);
   }
   bench.end(n);
 }
diff --git a/benchmark/buffers/buffer-indexof.js b/benchmark/buffers/buffer-indexof.js
index c575f54b6a638c..6f10033020bc74 100644
--- a/benchmark/buffers/buffer-indexof.js
+++ b/benchmark/buffers/buffer-indexof.js
@@ -1,5 +1,7 @@
+'use strict';
 var common = require('../common.js');
 var fs = require('fs');
+const path = require('path');
 
 var bench = common.createBenchmark(main, {
   search: ['@', 'SQ', '10x', '--l', 'Alice', 'Gryphon', 'Panther',
@@ -14,7 +16,9 @@ var bench = common.createBenchmark(main, {
 
 function main(conf) {
   var iter = (conf.iter) * 100000;
-  var aliceBuffer = fs.readFileSync(__dirname + '/../fixtures/alice.html');
+  var aliceBuffer = fs.readFileSync(
+    path.resolve(__dirname, '../fixtures/alice.html')
+  );
   var search = conf.search;
   var encoding = conf.encoding;
 
diff --git a/benchmark/buffers/buffer-iterate.js b/benchmark/buffers/buffer-iterate.js
index 77a0b59b8ac081..fb8abc1aee1c63 100644
--- a/benchmark/buffers/buffer-iterate.js
+++ b/benchmark/buffers/buffer-iterate.js
@@ -1,3 +1,4 @@
+'use strict';
 var SlowBuffer = require('buffer').SlowBuffer;
 var common = require('../common.js');
 var assert = require('assert');
diff --git a/benchmark/buffers/buffer-read.js b/benchmark/buffers/buffer-read.js
index 92138bccef99d6..2810aa1b463321 100644
--- a/benchmark/buffers/buffer-read.js
+++ b/benchmark/buffers/buffer-read.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 
 var bench = common.createBenchmark(main, {
@@ -21,10 +22,10 @@ function main(conf) {
 
   buff.writeDoubleLE(0, 0, noAssert);
   var testFunction = new Function('buff', [
-    "for (var i = 0; i !== " + len + "; i++) {",
-    "  buff." + fn + "(0, " + JSON.stringify(noAssert) + ");",
-    "}"
-  ].join("\n"));
+    'for (var i = 0; i !== ' + len + '; i++) {',
+    '  buff.' + fn + '(0, ' + JSON.stringify(noAssert) + ');',
+    '}'
+  ].join('\n'));
   bench.start();
   testFunction(buff);
   bench.end(len / 1e6);
diff --git a/benchmark/buffers/buffer-slice.js b/benchmark/buffers/buffer-slice.js
index f632fa64adff11..70cf3a705c0d8b 100644
--- a/benchmark/buffers/buffer-slice.js
+++ b/benchmark/buffers/buffer-slice.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var SlowBuffer = require('buffer').SlowBuffer;
 
diff --git a/benchmark/buffers/buffer-tostring.js b/benchmark/buffers/buffer-tostring.js
index 948052042d677b..f71c2b9a2b5127 100644
--- a/benchmark/buffers/buffer-tostring.js
+++ b/benchmark/buffers/buffer-tostring.js
@@ -14,12 +14,13 @@ function main(conf) {
   const n = conf.n | 0;
   const buf = Buffer(len).fill(42);
 
+  var i;
   bench.start();
   if (arg) {
-    for (var i = 0; i < n; i += 1)
+    for (i = 0; i < n; i += 1)
       buf.toString('utf8');
   } else {
-    for (var i = 0; i < n; i += 1)
+    for (i = 0; i < n; i += 1)
       buf.toString();
   }
   bench.end(n);
diff --git a/benchmark/buffers/buffer-write.js b/benchmark/buffers/buffer-write.js
index 2a2a0e37e3adda..4e07fc511be12a 100644
--- a/benchmark/buffers/buffer-write.js
+++ b/benchmark/buffers/buffer-write.js
@@ -1,4 +1,4 @@
-
+'use strict';
 var common = require('../common.js');
 var bench = common.createBenchmark(main, {
   noAssert: [false, true],
@@ -48,10 +48,10 @@ function main(conf) {
 function benchInt(buff, fn, len, noAssert) {
   var m = mod[fn];
   var testFunction = new Function('buff', [
-    "for (var i = 0; i !== " + len + "; i++) {",
-    "  buff." + fn + "(i & " + m + ", 0, " + JSON.stringify(noAssert) + ");",
-    "}"
-  ].join("\n"));
+    'for (var i = 0; i !== ' + len + '; i++) {',
+    '  buff.' + fn + '(i & ' + m + ', 0, ' + JSON.stringify(noAssert) + ');',
+    '}'
+  ].join('\n'));
   bench.start();
   testFunction(buff);
   bench.end(len / 1e6);
@@ -59,10 +59,10 @@ function benchInt(buff, fn, len, noAssert) {
 
 function benchFloat(buff, fn, len, noAssert) {
   var testFunction = new Function('buff', [
-    "for (var i = 0; i !== " + len + "; i++) {",
-    "  buff." + fn + "(i, 0, " + JSON.stringify(noAssert) + ");",
-    "}"
-  ].join("\n"));
+    'for (var i = 0; i !== ' + len + '; i++) {',
+    '  buff.' + fn + '(i, 0, ' + JSON.stringify(noAssert) + ');',
+    '}'
+  ].join('\n'));
   bench.start();
   testFunction(buff);
   bench.end(len / 1e6);
diff --git a/benchmark/buffers/dataview-set.js b/benchmark/buffers/dataview-set.js
index ce0064edb6e0cd..ab9c1d1d23b736 100644
--- a/benchmark/buffers/dataview-set.js
+++ b/benchmark/buffers/dataview-set.js
@@ -1,4 +1,4 @@
-
+'use strict';
 var common = require('../common.js');
 var bench = common.createBenchmark(main, {
   type: ['Uint8', 'Uint16LE', 'Uint16BE',
diff --git a/benchmark/common.js b/benchmark/common.js
index 511ae384f418bf..69c3d00ee2e1f1 100644
--- a/benchmark/common.js
+++ b/benchmark/common.js
@@ -1,3 +1,4 @@
+'use strict';
 var assert = require('assert');
 var fs = require('fs');
 var path = require('path');
@@ -27,7 +28,7 @@ if (module === require.main) {
   var tests = fs.readdirSync(dir);
 
   if (testFilter) {
-    var filteredTests = tests.filter(function(item){
+    var filteredTests = tests.filter(function(item) {
       if (item.lastIndexOf(testFilter) >= 0) {
         return item;
       }
@@ -48,7 +49,7 @@ function hasWrk() {
   if (result.error && result.error.code === 'ENOENT') {
     console.error('Couldn\'t locate `wrk` which is needed for running ' +
       'benchmarks. Check benchmark/README.md for further instructions.');
-      process.exit(-1);
+    process.exit(-1);
   }
 }
 
@@ -86,7 +87,7 @@ function Benchmark(fn, options) {
   this.options = options;
   this.config = parseOpts(options);
   this._name = require.main.filename.split(/benchmark[\/\\]/).pop();
-  this._start = [0,0];
+  this._start = [0, 0];
   this._started = false;
 
   var self = this;
@@ -120,7 +121,7 @@ Benchmark.prototype.http = function(p, args, cb) {
 
     if (code) {
       console.error('wrk failed with ' + code);
-      process.exit(code)
+      process.exit(code);
     }
     var match = out.match(regexp);
     var qps = match && +match[1];
@@ -140,8 +141,6 @@ Benchmark.prototype._run = function() {
   // some options weren't set.
   // run with all combinations
   var main = require.main.filename;
-  var settings = [];
-  var queueLen = 1;
   var options = this.options;
 
   var queue = Object.keys(options).reduce(function(set, key) {
@@ -192,7 +191,7 @@ function parseOpts(options) {
     if (!match || !match[1] || !match[2] || !options[match[1]]) {
       return null;
     } else {
-      conf[match[1]] = isFinite(match[2]) ? +match[2] : match[2]
+      conf[match[1]] = isFinite(match[2]) ? +match[2] : match[2];
       num--;
     }
   }
@@ -203,7 +202,7 @@ function parseOpts(options) {
     });
   }
   return num === 0 ? conf : null;
-};
+}
 
 Benchmark.prototype.start = function() {
   if (this._started)
@@ -221,8 +220,8 @@ Benchmark.prototype.end = function(operations) {
   if (typeof operations !== 'number')
     throw new Error('called end() without specifying operation count');
 
-  var time = elapsed[0] + elapsed[1]/1e9;
-  var rate = operations/time;
+  var time = elapsed[0] + elapsed[1] / 1e9;
+  var rate = operations / time;
   this.report(rate);
 };
 
diff --git a/benchmark/compare.js b/benchmark/compare.js
index edb116d0c64baa..44854aefa7b5e8 100644
--- a/benchmark/compare.js
+++ b/benchmark/compare.js
@@ -1,3 +1,4 @@
+'use strict';
 var usage = 'node benchmark/compare.js ' +
             '<node-binary1> <node-binary2> ' +
             '[--html] [--red|-r] [--green|-g] ' +
@@ -36,18 +37,19 @@ for (var i = 2; i < process.argv.length; i++) {
   }
 }
 
+var start, green, red, reset, end;
 if (!html) {
-  var start = '';
-  var green = '\033[1;32m';
-  var red = '\033[1;31m';
-  var reset = '\033[m';
-  var end = '';
+  start = '';
+  green = '\u001b[1;32m';
+  red = '\u001b[1;31m';
+  reset = '\u001b[m';
+  end = '';
 } else {
-  var start = '<pre style="background-color:#333;color:#eee">';
-  var green = '<span style="background-color:#0f0;color:#000">';
-  var red = '<span style="background-color:#f00;color:#fff">';
-  var reset = '</span>';
-  var end = '</pre>';
+  start = '<pre style="background-color:#333;color:#eee">';
+  green = '<span style="background-color:#0f0;color:#000">';
+  red = '<span style="background-color:#f00;color:#fff">';
+  reset = '</span>';
+  end = '</pre>';
 }
 
 var runBench = process.env.NODE_BENCH || 'bench';
@@ -75,10 +77,15 @@ function run() {
 
   var out = '';
   var child;
-  if (Array.isArray(benchmarks) && benchmarks.length)
-    child = spawn(node, ['benchmark/common.js'].concat(benchmarks), { env: env });
-  else
+  if (Array.isArray(benchmarks) && benchmarks.length) {
+    child = spawn(
+      node,
+      ['benchmark/common.js'].concat(benchmarks),
+      { env: env }
+    );
+  } else {
     child = spawn('make', [runBench], { env: env });
+  }
   child.stdout.setEncoding('utf8');
   child.stdout.on('data', function(c) {
     out += c;
@@ -134,9 +141,20 @@ function compare() {
     if (show === 'green' && !g || show === 'red' && !r)
       return;
 
-    var r0 = util.format('%s%s: %d%s', g, nodes[0], n0.toPrecision(5), g ? reset : '');
-    var r1 = util.format('%s%s: %d%s', r, nodes[1], n1.toPrecision(5), r ? reset : '');
-    var pct = c + pct + '%' + reset;
+    var r0 = util.format(
+      '%s%s: %d%s',
+      g,
+      nodes[0],
+      n0.toPrecision(5), g ? reset : ''
+    );
+    var r1 = util.format(
+      '%s%s: %d%s',
+      r,
+      nodes[1],
+      n1.toPrecision(5), r ? reset : ''
+    );
+    pct = c + pct + '%' + reset;
+
     var l = util.format('%s: %s %s', bench, r0, r1);
     maxLen = Math.max(l.length + pct.length, maxLen);
     return [l, pct];
diff --git a/benchmark/crypto/aes-gcm-throughput.js b/benchmark/crypto/aes-gcm-throughput.js
index 65e1713f0eb1c6..fc379b21b748bf 100644
--- a/benchmark/crypto/aes-gcm-throughput.js
+++ b/benchmark/crypto/aes-gcm-throughput.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var crypto = require('crypto');
 var keylen = {'aes-128-gcm': 16, 'aes-192-gcm': 24, 'aes-256-gcm': 32};
@@ -30,7 +31,7 @@ function AEAD_Bench(cipher, message, associate_data, key, iv, n, len) {
     var bob = crypto.createDecipheriv(cipher, key, iv);
     bob.setAuthTag(tag);
     bob.setAAD(associate_data);
-    var clear = bob.update(enc);
+    bob.update(enc);
     bob.final();
   }
 
diff --git a/benchmark/crypto/cipher-stream.js b/benchmark/crypto/cipher-stream.js
index 4e8198931729f4..5da6f2481ecbc3 100644
--- a/benchmark/crypto/cipher-stream.js
+++ b/benchmark/crypto/cipher-stream.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 
 var bench = common.createBenchmark(main, {
@@ -85,17 +86,17 @@ function streamWrite(alice, bob, message, encoding, writes) {
 
 function legacyWrite(alice, bob, message, encoding, writes) {
   var written = 0;
+  var enc, dec;
   for (var i = 0; i < writes; i++) {
-    var enc = alice.update(message, encoding);
-    var dec = bob.update(enc);
+    enc = alice.update(message, encoding);
+    dec = bob.update(enc);
     written += dec.length;
   }
-  var enc = alice.final();
-  var dec = bob.update(enc);
+  enc = alice.final();
+  dec = bob.update(enc);
   written += dec.length;
   dec = bob.final();
   written += dec.length;
-  var bits = written * 8;
   var gbits = written / (1024 * 1024 * 1024);
   bench.end(gbits);
 }
diff --git a/benchmark/crypto/hash-stream-creation.js b/benchmark/crypto/hash-stream-creation.js
index a14aa220120e4e..4bcd37f00aaae8 100644
--- a/benchmark/crypto/hash-stream-creation.js
+++ b/benchmark/crypto/hash-stream-creation.js
@@ -1,5 +1,6 @@
 // throughput benchmark
 // creates a single hasher, then pushes a bunch of data through it
+'use strict';
 var common = require('../common.js');
 var crypto = require('crypto');
 
@@ -20,9 +21,6 @@ function main(conf) {
     api = 'legacy';
   }
 
-  var crypto = require('crypto');
-  var assert = require('assert');
-
   var message;
   var encoding;
   switch (conf.type) {
diff --git a/benchmark/crypto/hash-stream-throughput.js b/benchmark/crypto/hash-stream-throughput.js
index 2e987f03f5a1cf..050bbeb1ae54d3 100644
--- a/benchmark/crypto/hash-stream-throughput.js
+++ b/benchmark/crypto/hash-stream-throughput.js
@@ -1,5 +1,6 @@
 // throughput benchmark
 // creates a single hasher, then pushes a bunch of data through it
+'use strict';
 var common = require('../common.js');
 var crypto = require('crypto');
 
@@ -19,9 +20,6 @@ function main(conf) {
     api = 'legacy';
   }
 
-  var crypto = require('crypto');
-  var assert = require('assert');
-
   var message;
   var encoding;
   switch (conf.type) {
diff --git a/benchmark/crypto/rsa-encrypt-decrypt-throughput.js b/benchmark/crypto/rsa-encrypt-decrypt-throughput.js
index 1cd7a5e632910b..cf0579134cfb62 100644
--- a/benchmark/crypto/rsa-encrypt-decrypt-throughput.js
+++ b/benchmark/crypto/rsa-encrypt-decrypt-throughput.js
@@ -1,3 +1,4 @@
+'use strict';
 // throughput benchmark in signing and verifying
 var common = require('../common.js');
 var crypto = require('crypto');
@@ -22,7 +23,6 @@ var bench = common.createBenchmark(main, {
 });
 
 function main(conf) {
-  var crypto = require('crypto');
   var message = (new Buffer(conf.len)).fill('b');
 
   bench.start();
@@ -38,7 +38,7 @@ function StreamWrite(algo, keylen, message, n, len) {
   var publicKey = RSA_PublicPem[keylen];
   for (var i = 0; i < n; i++) {
     var enc = crypto.privateEncrypt(privateKey, message);
-    var clear = crypto.publicDecrypt(publicKey, enc);
+    crypto.publicDecrypt(publicKey, enc);
   }
 
   bench.end(kbits);
diff --git a/benchmark/crypto/rsa-sign-verify-throughput.js b/benchmark/crypto/rsa-sign-verify-throughput.js
index fd4260417b2221..779cc8bca1c6a8 100644
--- a/benchmark/crypto/rsa-sign-verify-throughput.js
+++ b/benchmark/crypto/rsa-sign-verify-throughput.js
@@ -1,3 +1,4 @@
+'use strict';
 // throughput benchmark in signing and verifying
 var common = require('../common.js');
 var crypto = require('crypto');
@@ -23,7 +24,6 @@ var bench = common.createBenchmark(main, {
 });
 
 function main(conf) {
-  var crypto = require('crypto');
   var message = (new Buffer(conf.len)).fill('b');
 
   bench.start();
@@ -36,7 +36,6 @@ function StreamWrite(algo, keylen, message, writes, len) {
   var kbits = bits / (1024);
 
   var privateKey = RSA_PrivatePem[keylen];
-  var publicKey = RSA_PublicPem[keylen];
   var s = crypto.createSign(algo);
   var v = crypto.createVerify(algo);
 
@@ -45,7 +44,7 @@ function StreamWrite(algo, keylen, message, writes, len) {
     v.update(message);
   }
 
-  var sign = s.sign(privateKey, 'binary');
+  s.sign(privateKey, 'binary');
   s.end();
   v.end();
 
diff --git a/benchmark/events/ee-add-remove.js b/benchmark/events/ee-add-remove.js
index cd9fe3cb7de057..99d85367cb8d6f 100644
--- a/benchmark/events/ee-add-remove.js
+++ b/benchmark/events/ee-add-remove.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var events = require('events');
 
@@ -9,14 +10,15 @@ function main(conf) {
   var ee = new events.EventEmitter();
   var listeners = [];
 
-  for (var k = 0; k < 10; k += 1)
+  var k;
+  for (k = 0; k < 10; k += 1)
     listeners.push(function() {});
 
   bench.start();
   for (var i = 0; i < n; i += 1) {
-    for (var k = listeners.length; --k >= 0; /* empty */)
+    for (k = listeners.length; --k >= 0; /* empty */)
       ee.on('dummy', listeners[k]);
-    for (var k = listeners.length; --k >= 0; /* empty */)
+    for (k = listeners.length; --k >= 0; /* empty */)
       ee.removeListener('dummy', listeners[k]);
   }
   bench.end(n);
diff --git a/benchmark/events/ee-emit-multi-args.js b/benchmark/events/ee-emit-multi-args.js
index 78a892d457095d..b423c216b1ed73 100644
--- a/benchmark/events/ee-emit-multi-args.js
+++ b/benchmark/events/ee-emit-multi-args.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var EventEmitter = require('events').EventEmitter;
 
@@ -7,7 +8,6 @@ function main(conf) {
   var n = conf.n | 0;
 
   var ee = new EventEmitter();
-  var listeners = [];
 
   for (var k = 0; k < 10; k += 1)
     ee.on('dummy', function() {});
diff --git a/benchmark/events/ee-emit.js b/benchmark/events/ee-emit.js
index 4c45bd9b719665..87772222f0a467 100644
--- a/benchmark/events/ee-emit.js
+++ b/benchmark/events/ee-emit.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var EventEmitter = require('events').EventEmitter;
 
diff --git a/benchmark/events/ee-listener-count-on-prototype.js b/benchmark/events/ee-listener-count-on-prototype.js
index 8d536edd62739b..dfe7e27cd09144 100644
--- a/benchmark/events/ee-listener-count-on-prototype.js
+++ b/benchmark/events/ee-listener-count-on-prototype.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var EventEmitter = require('events').EventEmitter;
 
@@ -13,7 +14,7 @@ function main(conf) {
 
   bench.start();
   for (var i = 0; i < n; i += 1) {
-    var r = ee.listenerCount('dummy');
+    ee.listenerCount('dummy');
   }
   bench.end(n);
 }
diff --git a/benchmark/events/ee-listeners-many.js b/benchmark/events/ee-listeners-many.js
index 32721b32e56527..063732e1facb4b 100644
--- a/benchmark/events/ee-listeners-many.js
+++ b/benchmark/events/ee-listeners-many.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var EventEmitter = require('events').EventEmitter;
 
@@ -14,7 +15,7 @@ function main(conf) {
 
   bench.start();
   for (var i = 0; i < n; i += 1) {
-    var r = ee.listeners('dummy');
+    ee.listeners('dummy');
   }
   bench.end(n);
 }
diff --git a/benchmark/events/ee-listeners.js b/benchmark/events/ee-listeners.js
index 68339bc3eca77a..e91ca5078f5f98 100644
--- a/benchmark/events/ee-listeners.js
+++ b/benchmark/events/ee-listeners.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var EventEmitter = require('events').EventEmitter;
 
@@ -13,7 +14,7 @@ function main(conf) {
 
   bench.start();
   for (var i = 0; i < n; i += 1) {
-    var r = ee.listeners('dummy');
+    ee.listeners('dummy');
   }
   bench.end(n);
 }
diff --git a/benchmark/fs-write-stream-throughput.js b/benchmark/fs-write-stream-throughput.js
index b131d5b736fd38..4c767cf666e579 100644
--- a/benchmark/fs-write-stream-throughput.js
+++ b/benchmark/fs-write-stream-throughput.js
@@ -1,5 +1,5 @@
-
 // If there are no args, then this is the root.  Run all the benchmarks!
+'use strict';
 if (!process.argv[2])
   parent();
 else
@@ -39,24 +39,24 @@ function parent() {
 function runTest(dur, size, type) {
   if (type !== 'string')
     type = 'buffer';
+  var chunk;
   switch (type) {
     case 'string':
-      var chunk = new Array(size + 1).join('a');
+      chunk = new Array(size + 1).join('a');
       break;
     case 'buffer':
-      var chunk = new Buffer(size);
+      chunk = new Buffer(size);
       chunk.fill('a');
       break;
   }
 
-  var writes = 0;
   var fs = require('fs');
   try { fs.unlinkSync('write_stream_throughput'); } catch (e) {}
 
-  var start
+  var start;
   var end;
   function done() {
-    var time = end[0] + end[1]/1E9;
+    var time = end[0] + end[1] / 1E9;
     var written = fs.statSync('write_stream_throughput').size / 1024;
     var rate = (written / time).toFixed(2);
     console.log('fs_write_stream_dur_%d_size_%d_type_%s: %d',
diff --git a/benchmark/fs/read-stream-throughput.js b/benchmark/fs/read-stream-throughput.js
index a181a2df60291c..c305485cd5f8dc 100644
--- a/benchmark/fs/read-stream-throughput.js
+++ b/benchmark/fs/read-stream-throughput.js
@@ -1,4 +1,5 @@
 // test the throughput of the fs.WriteStream class.
+'use strict';
 
 var path = require('path');
 var common = require('../common.js');
@@ -11,7 +12,7 @@ var type, encoding, size;
 
 var bench = common.createBenchmark(main, {
   type: ['buf', 'asc', 'utf'],
-  size: [1024, 4096, 65535, 1024*1024]
+  size: [1024, 4096, 65535, 1024 * 1024]
 });
 
 function main(conf) {
diff --git a/benchmark/fs/readfile.js b/benchmark/fs/readfile.js
index ac3241901b931e..0f39f64f57c418 100644
--- a/benchmark/fs/readfile.js
+++ b/benchmark/fs/readfile.js
@@ -1,6 +1,7 @@
 // Call fs.readFile over and over again really fast.
 // Then see how many times it got called.
 // Yes, this is a silly benchmark.  Most benchmarks are silly.
+'use strict';
 
 var path = require('path');
 var common = require('../common.js');
diff --git a/benchmark/fs/write-stream-throughput.js b/benchmark/fs/write-stream-throughput.js
index 9ff58389c7959d..4f41d2b4bb4af3 100644
--- a/benchmark/fs/write-stream-throughput.js
+++ b/benchmark/fs/write-stream-throughput.js
@@ -1,4 +1,5 @@
 // test the throughput of the fs.WriteStream class.
+'use strict';
 
 var path = require('path');
 var common = require('../common.js');
@@ -28,7 +29,7 @@ function main(conf) {
       encoding = 'ascii';
       break;
     case 'utf':
-      chunk = new Array(Math.ceil(size/2) + 1).join('ü');
+      chunk = new Array(Math.ceil(size / 2) + 1).join('ü');
       encoding = 'utf8';
       break;
     default:
diff --git a/benchmark/http/_chunky_http_client.js b/benchmark/http/_chunky_http_client.js
index 24e14ca2bc9b0e..158be5a0eb6424 100644
--- a/benchmark/http/_chunky_http_client.js
+++ b/benchmark/http/_chunky_http_client.js
@@ -15,7 +15,6 @@ var bench = common.createBenchmark(main, {
 function main(conf) {
   var len = +conf.len;
   var num = +conf.num;
-  var type = conf.type;
   var todo = [];
   var headers = [];
   // Chose 7 because 9 showed "Connection error" / "Connection closed"
@@ -24,7 +23,7 @@ function main(conf) {
     headers.push(Array(i + 1).join('o'));
 
   function WriteHTTPHeaders(channel, has_keep_alive, extra_header_count) {
-    todo = []
+    todo = [];
     todo.push('GET / HTTP/1.1');
     todo.push('Host: localhost');
     todo.push('Connection: keep-alive');
@@ -63,7 +62,7 @@ function main(conf) {
   var socket = net.connect(PIPE, function() {
     bench.start();
     WriteHTTPHeaders(socket, 1, len);
-    socket.setEncoding('utf8')
+    socket.setEncoding('utf8');
     socket.on('data', function(d) {
       var did = false;
       var pattern = 'HTTP/1.1 200 OK\r\n';
@@ -73,7 +72,7 @@ function main(conf) {
         success += 1;
         did = true;
       } else {
-        pattern = 'HTTP/1.1 '
+        pattern = 'HTTP/1.1 ';
         if ((d.length === pattern.length && d === pattern) ||
             (d.length > pattern.length &&
              d.slice(0, pattern.length) === pattern)) {
diff --git a/benchmark/http/chunked.js b/benchmark/http/chunked.js
index 0589ff3166f04d..642f2962cdce78 100644
--- a/benchmark/http/chunked.js
+++ b/benchmark/http/chunked.js
@@ -6,9 +6,9 @@
 // always as hot as it could be.
 //
 // Verify that our assumptions are valid.
+'use strict';
 
 var common = require('../common.js');
-var PORT = common.PORT;
 
 var bench = common.createBenchmark(main, {
   num: [1, 4, 8, 16],
@@ -17,7 +17,7 @@ var bench = common.createBenchmark(main, {
 });
 
 function main(conf) {
-  http = require('http');
+  const http = require('http');
   var chunk = new Buffer(conf.size);
   chunk.fill('8');
 
diff --git a/benchmark/http/client-request-body.js b/benchmark/http/client-request-body.js
index 1c27dea2a2066e..befa3811ddd1c3 100644
--- a/benchmark/http/client-request-body.js
+++ b/benchmark/http/client-request-body.js
@@ -1,4 +1,5 @@
 // Measure the time it takes for the HTTP client to send a request body.
+'use strict';
 
 var common = require('../common.js');
 var http = require('http');
diff --git a/benchmark/http/cluster.js b/benchmark/http/cluster.js
index 6391704ff7836b..9934883f7c3fa4 100644
--- a/benchmark/http/cluster.js
+++ b/benchmark/http/cluster.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var PORT = common.PORT;
 
diff --git a/benchmark/http/end-vs-write-end.js b/benchmark/http/end-vs-write-end.js
index c17e2ffb45fa02..4e12e543f0bd92 100644
--- a/benchmark/http/end-vs-write-end.js
+++ b/benchmark/http/end-vs-write-end.js
@@ -6,9 +6,9 @@
 // always as hot as it could be.
 //
 // Verify that our assumptions are valid.
+'use strict';
 
 var common = require('../common.js');
-var PORT = common.PORT;
 
 var bench = common.createBenchmark(main, {
   type: ['asc', 'utf', 'buf'],
@@ -18,7 +18,7 @@ var bench = common.createBenchmark(main, {
 });
 
 function main(conf) {
-  http = require('http');
+  const http = require('http');
   var chunk;
   var len = conf.kb * 1024;
   switch (conf.type) {
@@ -27,7 +27,6 @@ function main(conf) {
       chunk.fill('x');
       break;
     case 'utf':
-      encoding = 'utf8';
       chunk = new Array(len / 2 + 1).join('ü');
       break;
     case 'asc':
diff --git a/benchmark/http/http_server_for_chunky_client.js b/benchmark/http/http_server_for_chunky_client.js
index dede7daa7cdc75..d85e15bcbed4e9 100644
--- a/benchmark/http/http_server_for_chunky_client.js
+++ b/benchmark/http/http_server_for_chunky_client.js
@@ -4,8 +4,8 @@ var path = require('path');
 var http = require('http');
 var fs = require('fs');
 var spawn = require('child_process').spawn;
-var common = require('../common.js')
-var test = require('../../test/common.js')
+require('../common.js');
+var test = require('../../test/common.js');
 var pep = path.dirname(process.argv[1]) + '/_chunky_http_client.js';
 var PIPE = test.PIPE;
 
@@ -38,17 +38,17 @@ try {
   child = spawn(process.execPath, [pep], { });
 
   child.on('error', function(err) {
-    throw new Error('spawn error: ' + err );
+    throw new Error('spawn error: ' + err);
   });
 
   child.stdout.pipe(process.stdout);
   child.stderr.pipe(process.stderr);
 
-  child.on('close', function (exitCode) {
+  child.on('close', function(exitCode) {
     server.close();
   });
 
-} catch(e) {
-  throw new Error('error: ' + e );
+} catch (e) {
+  throw new Error('error: ' + e);
 }
 
diff --git a/benchmark/http/simple.js b/benchmark/http/simple.js
index 5bff9283cb51a1..5449c49be97614 100644
--- a/benchmark/http/simple.js
+++ b/benchmark/http/simple.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var PORT = common.PORT;
 
@@ -11,7 +12,6 @@ var bench = common.createBenchmark(main, {
 
 function main(conf) {
   process.env.PORT = PORT;
-  var spawn = require('child_process').spawn;
   var server = require('../http_simple.js');
   setTimeout(function() {
     var path = '/' + conf.type + '/' + conf.length + '/' + conf.chunks;
diff --git a/benchmark/http_bench.js b/benchmark/http_bench.js
index a8f99e2f0e7978..354993a2706a95 100644
--- a/benchmark/http_bench.js
+++ b/benchmark/http_bench.js
@@ -1,3 +1,4 @@
+'use strict';
 var spawn = require('child_process').spawn;
 var cluster = require('cluster');
 var http = require('http');
@@ -20,10 +21,10 @@ for (var i = 2; i < process.argv.length; ++i) {
 }
 
 switch (options.mode) {
-case 'master': startMaster(); break;
-case 'server': startServer(); break;
-case 'client': startClient(); break;
-default: throw new Error('Bad mode: ' + options.mode);
+  case 'master': startMaster(); break;
+  case 'server': startServer(); break;
+  case 'client': startClient(); break;
+  default: throw new Error('Bad mode: ' + options.mode);
 }
 
 process.title = 'http_bench[' + options.mode + ']';
@@ -47,7 +48,7 @@ function startMaster() {
 
   var forkCount = 0;
 
-  cluster.on('online', function () {
+  cluster.on('online', function() {
     forkCount = forkCount + 1;
     if (forkCount === ~~options.servers) {
       var args = [
diff --git a/benchmark/http_server_lag.js b/benchmark/http_server_lag.js
index ca923d5b34afde..a3c18628ec68ba 100644
--- a/benchmark/http_server_lag.js
+++ b/benchmark/http_server_lag.js
@@ -1,3 +1,5 @@
+'use strict';
+
 var http = require('http');
 var port = parseInt(process.env.PORT, 10) || 8000;
 var defaultLag = parseInt(process.argv[2], 10) || 100;
@@ -6,7 +8,7 @@ http.createServer(function(req, res) {
   res.writeHead(200, { 'content-type': 'text/plain',
                        'content-length': '2' });
 
-  var lag = parseInt(req.url.split("/").pop(), 10) || defaultLag;
+  var lag = parseInt(req.url.split('/').pop(), 10) || defaultLag;
   setTimeout(function() {
     res.end('ok');
   }, lag);
diff --git a/benchmark/http_simple.js b/benchmark/http_simple.js
index 36800f2c9dba5a..0f36d3b6ce3ebd 100644
--- a/benchmark/http_simple.js
+++ b/benchmark/http_simple.js
@@ -1,13 +1,13 @@
-var path = require('path'),
-    exec = require('child_process').exec,
-    http = require('http');
+'use strict';
+
+var http = require('http');
 
 var port = parseInt(process.env.PORT || 8000);
 
 var fixed = makeString(20 * 1024, 'C'),
-    storedBytes = {},
-    storedBuffer = {},
-    storedUnicode = {};
+  storedBytes = {},
+  storedBuffer = {},
+  storedUnicode = {};
 
 var useDomains = process.env.NODE_USE_DOMAINS;
 
@@ -22,7 +22,7 @@ if (useDomains) {
   gdom.enter();
 }
 
-var server = module.exports = http.createServer(function (req, res) {
+var server = module.exports = http.createServer(function(req, res) {
   if (useDomains) {
     var dom = domain.create();
     dom.add(req);
@@ -36,29 +36,30 @@ var server = module.exports = http.createServer(function (req, res) {
   var n_chunks = parseInt(commands[3], 10);
   var status = 200;
 
+  var n, i;
   if (command == 'bytes') {
-    var n = ~~arg;
+    n = ~~arg;
     if (n <= 0)
-      throw new Error('bytes called with n <= 0')
+      throw new Error('bytes called with n <= 0');
     if (storedBytes[n] === undefined) {
       storedBytes[n] = makeString(n, 'C');
     }
     body = storedBytes[n];
 
   } else if (command == 'buffer') {
-    var n = ~~arg;
+    n = ~~arg;
     if (n <= 0)
       throw new Error('buffer called with n <= 0');
     if (storedBuffer[n] === undefined) {
       storedBuffer[n] = new Buffer(n);
-      for (var i = 0; i < n; i++) {
+      for (i = 0; i < n; i++) {
         storedBuffer[n][i] = 'C'.charCodeAt(0);
       }
     }
     body = storedBuffer[n];
 
   } else if (command == 'unicode') {
-    var n = ~~arg;
+    n = ~~arg;
     if (n <= 0)
       throw new Error('unicode called with n <= 0');
     if (storedUnicode[n] === undefined) {
@@ -93,7 +94,7 @@ var server = module.exports = http.createServer(function (req, res) {
     var len = body.length;
     var step = Math.floor(len / n_chunks) || 1;
 
-    for (var i = 0, n = (n_chunks - 1); i < n; ++i) {
+    for (i = 0, n = (n_chunks - 1); i < n; ++i) {
       res.write(body.slice(i * step, i * step + step));
     }
     res.end(body.slice((n_chunks - 1) * step));
@@ -114,7 +115,7 @@ function makeString(size, c) {
   return s;
 }
 
-server.listen(port, function () {
+server.listen(port, function() {
   if (module === require.main)
-    console.error('Listening at http://127.0.0.1:'+port+'/');
+    console.error('Listening at http://127.0.0.1:' + port + '/');
 });
diff --git a/benchmark/http_simple_auto.js b/benchmark/http_simple_auto.js
index f72cc01e60aa46..6f56879cc08aaa 100644
--- a/benchmark/http_simple_auto.js
+++ b/benchmark/http_simple_auto.js
@@ -6,94 +6,95 @@
 //   <args>   Arguments to pass to `ab`.
 //   <target> Target to benchmark, e.g. `bytes/1024` or `buffer/8192`.
 //
+'use strict';
 
-var path = require("path");
-var http = require("http");
-var spawn = require("child_process").spawn;
+var http = require('http');
+var spawn = require('child_process').spawn;
 
 var port = parseInt(process.env.PORT || 8000);
 
-var fixed = ""
-for (var i = 0; i < 20*1024; i++) {
-  fixed += "C";
+var fixed = '';
+var i;
+for (i = 0; i < 20 * 1024; i++) {
+  fixed += 'C';
 }
 
 var stored = {};
 var storedBuffer = {};
 
-var server = http.createServer(function (req, res) {
-  var commands = req.url.split("/");
+var server = http.createServer(function(req, res) {
+  var commands = req.url.split('/');
   var command = commands[1];
-  var body = "";
+  var body = '';
   var arg = commands[2];
   var n_chunks = parseInt(commands[3], 10);
   var status = 200;
+  var n;
 
-  if (command == "bytes") {
-    var n = parseInt(arg, 10)
+  if (command == 'bytes') {
+    n = parseInt(arg, 10);
     if (n <= 0)
-      throw "bytes called with n <= 0"
+      throw new Error('bytes called with n <= 0');
     if (stored[n] === undefined) {
-      stored[n] = "";
-      for (var i = 0; i < n; i++) {
-        stored[n] += "C"
+      stored[n] = '';
+      for (i = 0; i < n; i++) {
+        stored[n] += 'C';
       }
     }
     body = stored[n];
-
-  } else if (command == "buffer") {
-    var n = parseInt(arg, 10)
-    if (n <= 0) throw new Error("bytes called with n <= 0");
+  } else if (command == 'buffer') {
+    n = parseInt(arg, 10);
+    if (n <= 0) throw new Error('bytes called with n <= 0');
     if (storedBuffer[n] === undefined) {
       storedBuffer[n] = new Buffer(n);
-      for (var i = 0; i < n; i++) {
-        storedBuffer[n][i] = "C".charCodeAt(0);
+      for (i = 0; i < n; i++) {
+        storedBuffer[n][i] = 'C'.charCodeAt(0);
       }
     }
     body = storedBuffer[n];
 
-  } else if (command == "quit") {
+  } else if (command == 'quit') {
     res.connection.server.close();
-    body = "quitting";
+    body = 'quitting';
 
-  } else if (command == "fixed") {
+  } else if (command == 'fixed') {
     body = fixed;
 
-  } else if (command == "echo") {
-    res.writeHead(200, { "Content-Type": "text/plain",
-                         "Transfer-Encoding": "chunked" });
+  } else if (command == 'echo') {
+    res.writeHead(200, { 'Content-Type': 'text/plain',
+                         'Transfer-Encoding': 'chunked' });
     req.pipe(res);
     return;
 
   } else {
     status = 404;
-    body = "not found\n";
+    body = 'not found\n';
   }
 
   // example: http://localhost:port/bytes/512/4
   // sends a 512 byte body in 4 chunks of 128 bytes
   if (n_chunks > 0) {
-    res.writeHead(status, { "Content-Type": "text/plain",
-                            "Transfer-Encoding": "chunked" });
+    res.writeHead(status, { 'Content-Type': 'text/plain',
+                            'Transfer-Encoding': 'chunked' });
     // send body in chunks
     var len = body.length;
     var step = Math.floor(len / n_chunks) || 1;
 
-    for (var i = 0, n = (n_chunks - 1); i < n; ++i) {
+    for (i = 0, n = (n_chunks - 1); i < n; ++i) {
       res.write(body.slice(i * step, i * step + step));
     }
     res.end(body.slice((n_chunks - 1) * step));
   } else {
     var content_length = body.length.toString();
 
-    res.writeHead(status, { "Content-Type": "text/plain",
-                            "Content-Length": content_length });
+    res.writeHead(status, { 'Content-Type': 'text/plain',
+                            'Content-Length': content_length });
     res.end(body);
   }
 
 });
 
-server.listen(port, function () {
+server.listen(port, function() {
   var url = 'http://127.0.0.1:' + port + '/';
 
   var n = process.argv.length - 1;
@@ -109,10 +110,10 @@ server.listen(port, function () {
 });
 
 function dump_mm_stats() {
-  if (typeof gc != 'function') return;
+  if (typeof global.gc != 'function') return;
 
   var before = process.memoryUsage();
-  for (var i = 0; i < 10; ++i) gc();
+  for (var i = 0; i < 10; ++i) global.gc();
   var after = process.memoryUsage();
   setTimeout(print_stats, 250); // give GC time to settle
 
diff --git a/benchmark/http_simple_cluster.js b/benchmark/http_simple_cluster.js
index 9a886f2ee75dab..f48a2a2599a78f 100644
--- a/benchmark/http_simple_cluster.js
+++ b/benchmark/http_simple_cluster.js
@@ -1,9 +1,11 @@
-var cluster = require('cluster');
-var os = require('os');
+'use strict';
+const cluster = require('cluster');
+const os = require('os');
+const path = require('path');
 
 if (cluster.isMaster) {
   console.log('master running on pid %d', process.pid);
   for (var i = 0, n = os.cpus().length; i < n; ++i) cluster.fork();
 } else {
-  require(__dirname + '/http_simple.js');
+  require(path.join(__dirname, 'http_simple.js'));
 }
diff --git a/benchmark/idle_clients.js b/benchmark/idle_clients.js
index da96b8ac654db4..d294e685224d8b 100644
--- a/benchmark/idle_clients.js
+++ b/benchmark/idle_clients.js
@@ -1,27 +1,25 @@
-net = require('net');
+'use strict';
+const net = require('net');
 
 var errors = 0, connections = 0;
 
-var lastClose = 0;
-
-function connect () {
-  process.nextTick(function () {
+function connect() {
+  process.nextTick(function() {
     var s = net.Stream();
     var gotConnected = false;
     s.connect(9000);
 
-    s.on('connect', function () {
+    s.on('connect', function() {
       gotConnected = true;
       connections++;
       connect();
     });
 
-    s.on('close', function () {
+    s.on('close', function() {
       if (gotConnected) connections--;
-      lastClose = new Date();
     });
 
-    s.on('error', function () {
+    s.on('error', function() {
       errors++;
     });
   });
@@ -35,15 +33,15 @@ var oldConnections, oldErrors;
 // Try to start new connections every so often
 setInterval(connect, 5000);
 
-setInterval(function () {
+setInterval(function() {
   if (oldConnections != connections) {
     oldConnections = connections;
-    console.log("CLIENT %d connections: %d", process.pid, connections);
+    console.log('CLIENT %d connections: %d', process.pid, connections);
   }
 
   if (oldErrors != errors) {
     oldErrors = errors;
-    console.log("CLIENT %d errors: %d", process.pid, errors);
+    console.log('CLIENT %d errors: %d', process.pid, errors);
   }
 }, 1000);
 
diff --git a/benchmark/idle_server.js b/benchmark/idle_server.js
index 805c988811ea50..78e496690d1d4e 100644
--- a/benchmark/idle_server.js
+++ b/benchmark/idle_server.js
@@ -1,12 +1,11 @@
 'use strict';
 
 const net = require('net');
-var connections = 0;
 var errors = 0;
 
-var server = net.Server(function (socket) {
+var server = net.Server(function(socket) {
 
-  socket.on('error', function () {
+  socket.on('error', function() {
     errors++;
   });
 
@@ -18,14 +17,14 @@ server.listen(9000);
 
 var oldConnections, oldErrors;
 
-setInterval(function () {
+setInterval(function() {
   if (oldConnections != server.connections) {
     oldConnections = server.connections;
-    console.log("SERVER %d connections: %d", process.pid, server.connections);
+    console.log('SERVER %d connections: %d', process.pid, server.connections);
   }
 
   if (oldErrors != errors) {
     oldErrors = errors;
-    console.log("SERVER %d errors: %d", process.pid, errors);
+    console.log('SERVER %d errors: %d', process.pid, errors);
   }
 }, 1000);
diff --git a/benchmark/misc/child-process-read.js b/benchmark/misc/child-process-read.js
index 894dd55d301249..c1a7474aae32c1 100644
--- a/benchmark/misc/child-process-read.js
+++ b/benchmark/misc/child-process-read.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var bench = common.createBenchmark(main, {
   len: [64, 256, 1024, 4096, 32768],
diff --git a/benchmark/misc/domain-fn-args.js b/benchmark/misc/domain-fn-args.js
index 36e9e900299bb2..e9b24811c81689 100644
--- a/benchmark/misc/domain-fn-args.js
+++ b/benchmark/misc/domain-fn-args.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var domain = require('domain');
 
@@ -11,17 +12,17 @@ var gargs = [1, 2, 3];
 
 function main(conf) {
 
-  var args, ret, n = +conf.n;
-  var arguments = gargs.slice(0, conf.arguments);
+  var args, n = +conf.n;
+  var myArguments = gargs.slice(0, conf.arguments);
   bench.start();
 
   bdomain.enter();
   for (var i = 0; i < n; i++) {
-    if (arguments.length >= 2) {
-      args = Array.prototype.slice.call(arguments, 1);
-      ret = fn.apply(this, args);
+    if (myArguments.length >= 2) {
+      args = Array.prototype.slice.call(myArguments, 1);
+      fn.apply(this, args);
     } else {
-      ret = fn.call(this);
+      fn.call(this);
     }
   }
   bdomain.exit();
@@ -40,4 +41,4 @@ function fn(a, b, c) {
     c = 3;
 
   return a + b + c;
-}
\ No newline at end of file
+}
diff --git a/benchmark/misc/freelist.js b/benchmark/misc/freelist.js
index 76275000b08ffb..7956dc3d6b18c0 100644
--- a/benchmark/misc/freelist.js
+++ b/benchmark/misc/freelist.js
@@ -22,7 +22,7 @@ function main(conf) {
 
   bench.start();
 
-  for (i = 0; i < n; i++){
+  for (i = 0; i < n; i++) {
     // Return all the items to the pool
     for (j = 0; j < poolSize; j++) {
       list.free(used[j]);
diff --git a/benchmark/misc/function_call/index.js b/benchmark/misc/function_call/index.js
index fc8542a068ccd6..04f5627093893e 100644
--- a/benchmark/misc/function_call/index.js
+++ b/benchmark/misc/function_call/index.js
@@ -2,6 +2,7 @@
 // relative to a comparable C++ function.
 // Reports millions of calls per second.
 // Note that JS speed goes up, while cxx speed stays about the same.
+'use strict';
 
 var assert = require('assert');
 var common = require('../../common.js');
@@ -27,7 +28,7 @@ assert(js() === cxx());
 
 var bench = common.createBenchmark(main, {
   type: ['js', 'cxx'],
-  millions: [1,10,50]
+  millions: [1, 10, 50]
 });
 
 function main(conf) {
diff --git a/benchmark/misc/module-loader.js b/benchmark/misc/module-loader.js
index e53bc4d801164b..1df7a74cbe77e1 100644
--- a/benchmark/misc/module-loader.js
+++ b/benchmark/misc/module-loader.js
@@ -1,7 +1,7 @@
+'use strict';
 var fs = require('fs');
 var path = require('path');
 var common = require('../common.js');
-var packageJson = '{"main": "index.js"}';
 
 var tmpDirectory = path.join(__dirname, '..', 'tmp');
 var benchmarkDirectory = path.join(tmpDirectory, 'nodejs-benchmark-module');
@@ -18,8 +18,14 @@ function main(conf) {
   var n = +conf.thousands * 1e3;
   for (var i = 0; i <= n; i++) {
     fs.mkdirSync(benchmarkDirectory + i);
-    fs.writeFileSync(benchmarkDirectory + i + '/package.json', '{"main": "index.js"}');
-    fs.writeFileSync(benchmarkDirectory + i + '/index.js', 'module.exports = "";');
+    fs.writeFileSync(
+      benchmarkDirectory + i + '/package.json',
+      '{"main": "index.js"}'
+    );
+    fs.writeFileSync(
+      benchmarkDirectory + i + '/index.js',
+      'module.exports = "";'
+    );
   }
 
   measure(n);
@@ -38,7 +44,7 @@ function rmrf(location) {
     var things = fs.readdirSync(location);
     things.forEach(function(thing) {
       var cur = path.join(location, thing),
-          isDirectory = fs.statSync(cur).isDirectory();
+        isDirectory = fs.statSync(cur).isDirectory();
       if (isDirectory) {
         rmrf(cur);
         return;
diff --git a/benchmark/misc/next-tick-breadth.js b/benchmark/misc/next-tick-breadth.js
index 652408144373f6..87d130f3a7e102 100644
--- a/benchmark/misc/next-tick-breadth.js
+++ b/benchmark/misc/next-tick-breadth.js
@@ -1,3 +1,4 @@
+'use strict';
 
 var common = require('../common.js');
 var bench = common.createBenchmark(main, {
diff --git a/benchmark/misc/next-tick-depth.js b/benchmark/misc/next-tick-depth.js
index 8a2c8e0a6ae148..bc513d338d6d8c 100644
--- a/benchmark/misc/next-tick-depth.js
+++ b/benchmark/misc/next-tick-depth.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var bench = common.createBenchmark(main, {
   millions: [2]
diff --git a/benchmark/misc/spawn-echo.js b/benchmark/misc/spawn-echo.js
index 2b1b989e679b96..7c9e851aacb641 100644
--- a/benchmark/misc/spawn-echo.js
+++ b/benchmark/misc/spawn-echo.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var bench = common.createBenchmark(main, {
   thousands: [1]
diff --git a/benchmark/misc/startup.js b/benchmark/misc/startup.js
index aa5b4420f65903..34604911d250f3 100644
--- a/benchmark/misc/startup.js
+++ b/benchmark/misc/startup.js
@@ -1,10 +1,8 @@
+'use strict';
 var common = require('../common.js');
 var spawn = require('child_process').spawn;
 var path = require('path');
 var emptyJsFile = path.resolve(__dirname, '../../test/fixtures/semicolon.js');
-var starts = 100;
-var i = 0;
-var start;
 
 var bench = common.createBenchmark(startNode, {
   dur: [1]
@@ -14,7 +12,6 @@ function startNode(conf) {
   var dur = +conf.dur;
   var go = true;
   var starts = 0;
-  var open = 0;
 
   setTimeout(function() {
     go = false;
diff --git a/benchmark/misc/string-creation.js b/benchmark/misc/string-creation.js
index 74dabd66c02501..59fb1b52b4ec12 100644
--- a/benchmark/misc/string-creation.js
+++ b/benchmark/misc/string-creation.js
@@ -1,8 +1,9 @@
+'use strict';
 
 var common = require('../common.js');
 var bench = common.createBenchmark(main, {
   millions: [100]
-})
+});
 
 function main(conf) {
   var n = +conf.millions * 1e6;
@@ -10,7 +11,7 @@ function main(conf) {
   var s;
   for (var i = 0; i < n; i++) {
     s = '01234567890';
-    s[1] = "a";
+    s[1] = 'a';
   }
   bench.end(n / 1e6);
 }
diff --git a/benchmark/misc/string-decoder.js b/benchmark/misc/string-decoder.js
index 14563cee0d7754..b10b0a6e9cbd48 100644
--- a/benchmark/misc/string-decoder.js
+++ b/benchmark/misc/string-decoder.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var StringDecoder = require('string_decoder').StringDecoder;
 
@@ -21,6 +22,7 @@ function main(conf) {
   var chunks = [];
   var str = '';
   var isBase64 = (encoding === 'base64-ascii' || encoding === 'base64-utf8');
+  var i;
 
   if (encoding === 'ascii' || encoding === 'base64-ascii')
     alpha = ASC_ALPHA;
@@ -31,7 +33,7 @@ function main(conf) {
 
   var sd = new StringDecoder(isBase64 ? 'base64' : encoding);
 
-  for (var i = 0; i < inLen; ++i) {
+  for (i = 0; i < inLen; ++i) {
     if (i > 0 && (i % chunkLen) === 0 && !isBase64) {
       chunks.push(new Buffer(str, encoding));
       str = '';
@@ -52,7 +54,7 @@ function main(conf) {
   var nChunks = chunks.length;
 
   bench.start();
-  for (var i = 0; i < n; ++i) {
+  for (i = 0; i < n; ++i) {
     for (var j = 0; j < nChunks; ++j)
       sd.write(chunks[j]);
   }
diff --git a/benchmark/misc/timers.js b/benchmark/misc/timers.js
index 23f571bb4528a1..13b18fffc5ead7 100644
--- a/benchmark/misc/timers.js
+++ b/benchmark/misc/timers.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 
 var bench = common.createBenchmark(main, {
diff --git a/benchmark/misc/url.js b/benchmark/misc/url.js
index 6c2799b6cb92b2..4b65300a9c580d 100644
--- a/benchmark/misc/url.js
+++ b/benchmark/misc/url.js
@@ -1,4 +1,5 @@
-var url = require('url')
+'use strict';
+var url = require('url');
 var n = 25 * 100;
 
 var urls = [
@@ -20,7 +21,7 @@ benchmark('parse()', url.parse);
 benchmark('format()', url.format);
 paths.forEach(function(p) {
   benchmark('resolve("' + p + '")', function(u) {
-    url.resolve(u, p)
+    url.resolve(u, p);
   });
 });
 
diff --git a/benchmark/misc/v8-bench.js b/benchmark/misc/v8-bench.js
index 0eb95aa9e2b2bc..0b9a5139ba23cf 100644
--- a/benchmark/misc/v8-bench.js
+++ b/benchmark/misc/v8-bench.js
@@ -1,4 +1,5 @@
 // compare with "google-chrome deps/v8/benchmarks/run.html"
+'use strict';
 var fs = require('fs');
 var path = require('path');
 var vm = require('vm');
@@ -19,4 +20,4 @@ global.load = function(filename) {
   global.RegExp = $RegExp;
 };
 
-load('run.js');
+global.load('run.js');
diff --git a/benchmark/net/dgram.js b/benchmark/net/dgram.js
index 6a0c5501c62c8e..fed5b873929b98 100644
--- a/benchmark/net/dgram.js
+++ b/benchmark/net/dgram.js
@@ -1,3 +1,4 @@
+'use strict';
 // test UDP send/recv throughput
 
 var common = require('../common.js');
@@ -18,7 +19,6 @@ var len;
 var num;
 var type;
 var chunk;
-var encoding;
 
 function main(conf) {
   dur = +conf.dur;
diff --git a/benchmark/net/net-c2s-cork.js b/benchmark/net/net-c2s-cork.js
index 5f8e0fa4357b99..5d1c8a7495ead9 100644
--- a/benchmark/net/net-c2s-cork.js
+++ b/benchmark/net/net-c2s-cork.js
@@ -1,4 +1,5 @@
 // test the speed of .pipe() with sockets
+'use strict';
 
 var common = require('../common.js');
 var PORT = common.PORT;
@@ -35,7 +36,6 @@ function main(conf) {
       break;
     default:
       throw new Error('invalid type: ' + type);
-      break;
   }
 
   server();
@@ -77,8 +77,8 @@ function server() {
     socket.on('connect', function() {
       bench.start();
 
-      socket.on('drain', send)
-      send()
+      socket.on('drain', send);
+      send();
 
       setTimeout(function() {
         var bytes = writer.received;
@@ -88,7 +88,7 @@ function server() {
 
       function send() {
         socket.cork();
-        while(socket.write(chunk, encoding)) {}
+        while (socket.write(chunk, encoding)) {}
         socket.uncork();
       }
     });
diff --git a/benchmark/net/net-c2s.js b/benchmark/net/net-c2s.js
index 49de7c77c9265c..370ff4f138cafd 100644
--- a/benchmark/net/net-c2s.js
+++ b/benchmark/net/net-c2s.js
@@ -1,4 +1,5 @@
 // test the speed of .pipe() with sockets
+'use strict';
 
 var common = require('../common.js');
 var PORT = common.PORT;
@@ -35,7 +36,6 @@ function main(conf) {
       break;
     default:
       throw new Error('invalid type: ' + type);
-      break;
   }
 
   server();
diff --git a/benchmark/net/net-pipe.js b/benchmark/net/net-pipe.js
index 2a5ed8e483659e..ea8af249a35b50 100644
--- a/benchmark/net/net-pipe.js
+++ b/benchmark/net/net-pipe.js
@@ -1,4 +1,5 @@
 // test the speed of .pipe() with sockets
+'use strict';
 
 var common = require('../common.js');
 var PORT = common.PORT;
@@ -35,7 +36,6 @@ function main(conf) {
       break;
     default:
       throw new Error('invalid type: ' + type);
-      break;
   }
 
   server();
diff --git a/benchmark/net/net-s2c.js b/benchmark/net/net-s2c.js
index 79e22494a7b8ed..af40d8d58d8852 100644
--- a/benchmark/net/net-s2c.js
+++ b/benchmark/net/net-s2c.js
@@ -1,4 +1,5 @@
 // test the speed of .pipe() with sockets
+'use strict';
 
 var common = require('../common.js');
 var PORT = common.PORT;
@@ -35,7 +36,6 @@ function main(conf) {
       break;
     default:
       throw new Error('invalid type: ' + type);
-      break;
   }
 
   server();
diff --git a/benchmark/net/tcp-raw-c2s.js b/benchmark/net/tcp-raw-c2s.js
index 0039313f5235ad..e13af85c6774dd 100644
--- a/benchmark/net/tcp-raw-c2s.js
+++ b/benchmark/net/tcp-raw-c2s.js
@@ -1,5 +1,6 @@
 // In this benchmark, we connect a client to the server, and write
 // as many bytes as we can in the specified time (default = 10s)
+'use strict';
 
 var common = require('../common.js');
 var util = require('util');
@@ -89,7 +90,6 @@ function client() {
       break;
     default:
       throw new Error('invalid type: ' + type);
-      break;
   }
 
   var clientHandle = new TCP();
diff --git a/benchmark/net/tcp-raw-pipe.js b/benchmark/net/tcp-raw-pipe.js
index 1504d11db5fa53..c05c816855e7a6 100644
--- a/benchmark/net/tcp-raw-pipe.js
+++ b/benchmark/net/tcp-raw-pipe.js
@@ -1,5 +1,6 @@
 // In this benchmark, we connect a client to the server, and write
 // as many bytes as we can in the specified time (default = 10s)
+'use strict';
 
 var common = require('../common.js');
 var util = require('util');
@@ -87,7 +88,6 @@ function client() {
       break;
     default:
       throw new Error('invalid type: ' + type);
-      break;
   }
 
   var clientHandle = new TCP();
diff --git a/benchmark/net/tcp-raw-s2c.js b/benchmark/net/tcp-raw-s2c.js
index 502586c2a05e29..822a74c679db12 100644
--- a/benchmark/net/tcp-raw-s2c.js
+++ b/benchmark/net/tcp-raw-s2c.js
@@ -1,5 +1,6 @@
 // In this benchmark, we connect a client to the server, and write
 // as many bytes as we can in the specified time (default = 10s)
+'use strict';
 
 var common = require('../common.js');
 var util = require('util');
@@ -61,7 +62,6 @@ function server() {
         break;
       default:
         throw new Error('invalid type: ' + type);
-        break;
     }
 
     clientHandle.readStart();
diff --git a/benchmark/path/basename.js b/benchmark/path/basename.js
index 57d9492746b32c..6c710dbb58ceb6 100644
--- a/benchmark/path/basename.js
+++ b/benchmark/path/basename.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var path = require('path');
 var v8 = require('v8');
diff --git a/benchmark/path/dirname.js b/benchmark/path/dirname.js
index e95adf28811a4e..4a9c04158cdee6 100644
--- a/benchmark/path/dirname.js
+++ b/benchmark/path/dirname.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var path = require('path');
 var v8 = require('v8');
diff --git a/benchmark/path/extname.js b/benchmark/path/extname.js
index c655ee7e3e160a..4f7c6b542d21c4 100644
--- a/benchmark/path/extname.js
+++ b/benchmark/path/extname.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var path = require('path');
 var v8 = require('v8');
diff --git a/benchmark/path/format.js b/benchmark/path/format.js
index bc77f888116963..478a30cbaedbd2 100644
--- a/benchmark/path/format.js
+++ b/benchmark/path/format.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var path = require('path');
 var v8 = require('v8');
diff --git a/benchmark/path/isAbsolute.js b/benchmark/path/isAbsolute.js
index d4c79b99cdbeb7..0d412f925388c6 100644
--- a/benchmark/path/isAbsolute.js
+++ b/benchmark/path/isAbsolute.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var path = require('path');
 var v8 = require('v8');
diff --git a/benchmark/path/join.js b/benchmark/path/join.js
index 58f4dc3e1e9e44..0262e25d249cb0 100644
--- a/benchmark/path/join.js
+++ b/benchmark/path/join.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var path = require('path');
 var v8 = require('v8');
diff --git a/benchmark/path/normalize.js b/benchmark/path/normalize.js
index 6f7f05e4f9e1c8..56a637f401c0cc 100644
--- a/benchmark/path/normalize.js
+++ b/benchmark/path/normalize.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var path = require('path');
 var v8 = require('v8');
diff --git a/benchmark/path/parse.js b/benchmark/path/parse.js
index f3fbb2a1f5c98f..2afc143090c6c8 100644
--- a/benchmark/path/parse.js
+++ b/benchmark/path/parse.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var path = require('path');
 var v8 = require('v8');
diff --git a/benchmark/path/relative.js b/benchmark/path/relative.js
index d61c3961a62d8b..0a72a2ad7bf726 100644
--- a/benchmark/path/relative.js
+++ b/benchmark/path/relative.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var path = require('path');
 var v8 = require('v8');
diff --git a/benchmark/path/resolve.js b/benchmark/path/resolve.js
index 375e8b134ba0ea..5235b94b74d328 100644
--- a/benchmark/path/resolve.js
+++ b/benchmark/path/resolve.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var path = require('path');
 var v8 = require('v8');
diff --git a/benchmark/querystring/querystring-parse.js b/benchmark/querystring/querystring-parse.js
index 6a4d9f5e6169f4..1019a941dfdecb 100644
--- a/benchmark/querystring/querystring-parse.js
+++ b/benchmark/querystring/querystring-parse.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var querystring = require('querystring');
 var v8 = require('v8');
@@ -27,8 +28,16 @@ function main(conf) {
   v8.setFlagsFromString('--allow_natives_syntax');
   eval('%OptimizeFunctionOnNextCall(querystring.parse)');
 
-  bench.start();
-  for (var i = 0; i < n; i += 1)
-    querystring.parse(input);
-  bench.end(n);
+  var i;
+  if (type !== 'multicharsep') {
+    bench.start();
+    for (i = 0; i < n; i += 1)
+      querystring.parse(input);
+    bench.end(n);
+  } else {
+    bench.start();
+    for (i = 0; i < n; i += 1)
+      querystring.parse(input, '&&&&&&&&&&');
+    bench.end(n);
+  }
 }
diff --git a/benchmark/querystring/querystring-stringify.js b/benchmark/querystring/querystring-stringify.js
index d4bb95c21e5af4..c2f38554166aa4 100644
--- a/benchmark/querystring/querystring-stringify.js
+++ b/benchmark/querystring/querystring-stringify.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var querystring = require('querystring');
 var v8 = require('v8');
diff --git a/benchmark/report-startup-memory.js b/benchmark/report-startup-memory.js
index 14e56231ec2ddd..6d796307f4f437 100644
--- a/benchmark/report-startup-memory.js
+++ b/benchmark/report-startup-memory.js
@@ -1 +1,2 @@
+'use strict';
 console.log(process.memoryUsage().rss);
diff --git a/benchmark/static_http_server.js b/benchmark/static_http_server.js
index b3a83785e3792f..804f83c208bb39 100644
--- a/benchmark/static_http_server.js
+++ b/benchmark/static_http_server.js
@@ -1,9 +1,10 @@
+'use strict';
 var http = require('http');
 
 var concurrency = 30;
 var port = 12346;
 var n = 700;
-var bytes = 1024*5;
+var bytes = 1024 * 5;
 
 var requests = 0;
 var responses = 0;
@@ -19,7 +20,7 @@ var server = http.createServer(function(req, res) {
     'Content-Length': body.length
   });
   res.end(body);
-})
+});
 
 server.listen(port, function() {
   var agent = new http.Agent();
diff --git a/benchmark/tls/throughput.js b/benchmark/tls/throughput.js
index 442eba338ed643..7b545267ace7fe 100644
--- a/benchmark/tls/throughput.js
+++ b/benchmark/tls/throughput.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var bench = common.createBenchmark(main, {
   dur: [5],
@@ -30,7 +31,7 @@ function main(conf) {
       encoding = 'ascii';
       break;
     case 'utf':
-      chunk = new Array(size/2 + 1).join('ü');
+      chunk = new Array(size / 2 + 1).join('ü');
       encoding = 'utf8';
       break;
     default:
@@ -44,16 +45,16 @@ function main(conf) {
 
   server = tls.createServer(options, onConnection);
   setTimeout(done, dur * 1000);
+  var conn;
   server.listen(common.PORT, function() {
     var opt = { port: common.PORT, rejectUnauthorized: false };
-    var conn = tls.connect(opt, function() {
+    conn = tls.connect(opt, function() {
       bench.start();
       conn.on('drain', write);
       write();
     });
 
     function write() {
-      var i = 0;
       while (false !== conn.write(chunk, encoding));
     }
   });
@@ -68,7 +69,8 @@ function main(conf) {
   function done() {
     var mbits = (received * 8) / (1024 * 1024);
     bench.end(mbits);
-    conn.destroy();
+    if (conn)
+      conn.destroy();
     server.close();
   }
 }
diff --git a/benchmark/tls/tls-connect.js b/benchmark/tls/tls-connect.js
index 96c9c5ab275f9d..a265989e04db24 100644
--- a/benchmark/tls/tls-connect.js
+++ b/benchmark/tls/tls-connect.js
@@ -1,7 +1,7 @@
-var assert = require('assert'),
-    fs = require('fs'),
-    path = require('path'),
-    tls = require('tls');
+'use strict';
+var fs = require('fs'),
+  path = require('path'),
+  tls = require('tls');
 
 var common = require('../common.js');
 var bench = common.createBenchmark(main, {
@@ -21,10 +21,10 @@ function main(conf) {
   concurrency = +conf.concurrency;
 
   var cert_dir = path.resolve(__dirname, '../../test/fixtures'),
-      options = { key: fs.readFileSync(cert_dir + '/test_key.pem'),
-                  cert: fs.readFileSync(cert_dir + '/test_cert.pem'),
-                  ca: [ fs.readFileSync(cert_dir + '/test_ca.pem') ],
-                  ciphers: 'AES256-GCM-SHA384' };
+    options = { key: fs.readFileSync(cert_dir + '/test_key.pem'),
+                cert: fs.readFileSync(cert_dir + '/test_cert.pem'),
+                ca: [ fs.readFileSync(cert_dir + '/test_ca.pem') ],
+                ciphers: 'AES256-GCM-SHA384' };
 
   server = tls.createServer(options, onConnection);
   server.listen(common.PORT, onListening);
diff --git a/benchmark/url/url-parse.js b/benchmark/url/url-parse.js
index ffa47c4ccd6105..89679548b8f193 100644
--- a/benchmark/url/url-parse.js
+++ b/benchmark/url/url-parse.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var url = require('url');
 var v8 = require('v8');
diff --git a/benchmark/url/url-resolve.js b/benchmark/url/url-resolve.js
index 5f6c1f7600ce4e..18f67e82e30787 100644
--- a/benchmark/url/url-resolve.js
+++ b/benchmark/url/url-resolve.js
@@ -1,3 +1,4 @@
+'use strict';
 var common = require('../common.js');
 var url = require('url');
 var v8 = require('v8');
diff --git a/benchmark/util/inspect.js b/benchmark/util/inspect.js
index 8a59e6b48e54df..3312bd683ba81b 100644
--- a/benchmark/util/inspect.js
+++ b/benchmark/util/inspect.js
@@ -1,3 +1,4 @@
+'use strict';
 var util = require('util');
 
 var common = require('../common.js');
@@ -9,7 +10,7 @@ function main(conf) {
 
   bench.start();
   for (var i = 0; i < n; i += 1) {
-    var r = util.inspect({a: 'a', b: 'b', c: 'c', d: 'd'});
+    util.inspect({a: 'a', b: 'b', c: 'c', d: 'd'});
   }
   bench.end(n);
 }
diff --git a/vcbuild.bat b/vcbuild.bat
index 1a6a0e45c6f678..e955860b8a464e 100644
--- a/vcbuild.bat
+++ b/vcbuild.bat
@@ -258,7 +258,7 @@ goto jslint
 :jslint
 if not defined jslint goto exit
 echo running jslint
-%config%\node tools\eslint\bin\eslint.js lib src test tools\doc tools\eslint-rules --rulesdir tools\eslint-rules
+%config%\node tools\eslint\bin\eslint.js benchmark lib src test tools\doc tools\eslint-rules --rulesdir tools\eslint-rules
 goto exit
 
 :create-msvs-files-failed