diff --git a/crypto_stream.js b/crypto_stream.js
index a7e11ee..a130dab 100644
--- a/crypto_stream.js
+++ b/crypto_stream.js
@@ -4,14 +4,15 @@ exports.crypto_stream_KEYBYTES = 32
 exports.crypto_stream_NONCEBYTES = 24
 exports.crypto_stream_PRIMITIVE = 'xsalsa20'
 
-exports.crypto_stream = function (out, nonce, key) {
-  out.fill(0)
-  exports.crypto_stream_xor(out, out, nonce, key)
+exports.crypto_stream = function (c, cpos, clen, nonce, key) {
+  c.fill(0)
+  exports.crypto_stream_xor(c, 0, c, 0, 0, nonce, key)
 }
 
-exports.crypto_stream_xor = function (out, inp, nonce, key) {
+exports.crypto_stream_xor = function (c, cpos, m, mpos, clen, nonce, key) {
   var xor = xsalsa20(nonce, key)
-  xor.update(inp, out)
+
+  xor.update(m, c)
   xor.final()
 }
 
diff --git a/index.js b/index.js
index c7b26de..785c4fb 100644
--- a/index.js
+++ b/index.js
@@ -1,11 +1,8 @@
 'use strict';
 
-var xsalsa20 = require('xsalsa20')
-
 // Based on https://github.com/dchest/tweetnacl-js/blob/6dcbcaf5f5cbfd313f2dcfe763db35c828c8ff5b/nacl-fast.js.
 
 var sodium = module.exports
-var cs = require('./crypto_stream')
 
 // Ported in 2014 by Dmitry Chestnykh and Devi Mandiri.
 // Public domain.
@@ -1859,9 +1856,7 @@ function cleanup(arr) {
   for (var i = 0; i < arr.length; i++) arr[i] = 0;
 }
 
-function check (buf, len) {
-  if (!buf || (len && buf.length < len)) throw new Error('Argument must be a buffer' + (len ? ' of length ' + len : ''))
-}
+forward(require('./crypto_stream'))
 
 function forward (submodule) {
   Object.keys(submodule).forEach(function (prop) {