diff --git a/.travis.yml b/.travis.yml
index f7227d0..b07fd55 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,9 +1,6 @@
 sudo: false
 language: node_js
 node_js:
-  - "0.10"
-  - "0.11"
-  - "0.12"
   - "4"
   - "5"
   - "6"
diff --git a/index.js b/index.js
index e455590..34903b7 100644
--- a/index.js
+++ b/index.js
@@ -11,7 +11,7 @@ function throwIfNotStringOrBuffer (val, prefix) {
 function HashBase (blockSize) {
   Transform.call(this)
 
-  this._block = new Buffer(blockSize)
+  this._block = Buffer.allocUnsafe(blockSize)
   this._blockSize = blockSize
   this._blockOffset = 0
   this._length = [0, 0, 0, 0]
@@ -46,7 +46,7 @@ HashBase.prototype._flush = function (callback) {
 HashBase.prototype.update = function (data, encoding) {
   throwIfNotStringOrBuffer(data, 'Data')
   if (this._finalized) throw new Error('Digest already called')
-  if (!Buffer.isBuffer(data)) data = new Buffer(data, encoding)
+  if (!Buffer.isBuffer(data)) data = Buffer.from(data, encoding)
 
   // consume data
   var block = this._block
diff --git a/package.json b/package.json
index cd076f3..ae7ad71 100644
--- a/package.json
+++ b/package.json
@@ -33,5 +33,8 @@
     "nyc": "^8.3.2",
     "standard": "*",
     "tape": "^4.2.0"
+  },
+  "engines": {
+    "node": ">=4"
   }
 }
diff --git a/test/index.js b/test/index.js
index 28a2a14..95fdab2 100644
--- a/test/index.js
+++ b/test/index.js
@@ -3,7 +3,7 @@ var test = require('tape')
 var HashBase = require('../')
 
 var utf8text = 'УТФ-8 text'
-var utf8buf = new Buffer(utf8text, 'utf8')
+var utf8buf = Buffer.from(utf8text, 'utf8')
 function noop () {}
 
 function createHashBase (t) { t.base = new HashBase(64) }
@@ -38,7 +38,7 @@ test('HashBase#_transform', function (t) {
     t.plan(1)
     var err = new Error('hey')
     t.base.update = function () { throw err }
-    t.base._transform(new Buffer(0), 'buffer', function (_err) {
+    t.base._transform(Buffer.allocUnsafe(0), 'buffer', function (_err) {
       t.true(_err === err)
     })
     t.end()
@@ -52,7 +52,7 @@ test('HashBase#_flush', function (t) {
 
   t.test('should use HashBase#digest', function (t) {
     t.plan(2)
-    var buffer = new Buffer(0)
+    var buffer = Buffer.allocUnsafe(0)
     t.base.push = function (data) { t.true(data === buffer) }
     t.base.digest = function () { return buffer }
     t.base._flush(function (err) { t.same(err, null) })
@@ -92,13 +92,13 @@ test('HashBase#update', function (t) {
   t.test('should use HashBase#_update', function (t) {
     t.plan(1)
     t.base._update = t.pass
-    t.base.update(new Buffer(64))
+    t.base.update(Buffer.allocUnsafe(64))
     t.end()
   })
 
   t.test('default encoding is utf8', function (t) {
     t.plan(1)
-    var buffer = new Buffer(64)
+    var buffer = Buffer.allocUnsafe(64)
     buffer.fill(0)
     utf8buf.copy(buffer)
     t.base._update = function () { t.same(this._block, buffer) }
@@ -108,8 +108,7 @@ test('HashBase#update', function (t) {
 
   t.test('decode string with custom encoding', function (t) {
     t.plan(1)
-    var buffer = new Buffer(64)
-    buffer.fill(0x42)
+    var buffer = Buffer.allocUnsafe(64).fill(0x42)
     t.base._update = function () { t.same(this._block, buffer) }
     t.base.update(buffer.toString('hex'), 'hex')
     t.end()
@@ -117,13 +116,13 @@ test('HashBase#update', function (t) {
 
   t.test('data length is more than 2^32 bits', function (t) {
     t.base._length = [ Math.pow(2, 32) - 1, 0, 0, 0 ]
-    t.base.update(new Buffer(1))
+    t.base.update(Buffer.allocUnsafe(1))
     t.same(t.base._length, [ 7, 1, 0, 0 ])
     t.end()
   })
 
   t.test('should return `this`', function (t) {
-    t.same(t.base.update(new Buffer(0)), t.base)
+    t.same(t.base.update(Buffer.allocUnsafe(0)), t.base)
     t.end()
   })