diff --git a/lib/client/index.js b/lib/client/index.js
index 8faf8f4a2..3e4bc1225 100644
--- a/lib/client/index.js
+++ b/lib/client/index.js
@@ -4,7 +4,7 @@ var nThen = require("nthen");
 
 var Util = require("../../www/common/common-util");
 
-var Nacl = require("tweetnacl");
+var Nacl = require("tweetnacl/nacl-fast");
 
 var Client = module.exports;
 
diff --git a/rpc.js b/rpc.js
index 5a97cd572..d4bd41c9c 100644
--- a/rpc.js
+++ b/rpc.js
@@ -1,7 +1,7 @@
 /*@flow*/
 /*jshint esversion: 6 */
 /*  Use Nacl for checking signatures of messages */
-var Nacl = require("tweetnacl");
+var Nacl = require("tweetnacl/nacl-fast");
 
 /* globals Buffer*/
 /* globals process */
diff --git a/scripts/tests/test-rpc.js b/scripts/tests/test-rpc.js
index 178a07c0d..ddfe06655 100644
--- a/scripts/tests/test-rpc.js
+++ b/scripts/tests/test-rpc.js
@@ -3,7 +3,7 @@
 var Client = require("../../lib/client/");
 var Crypto = require("../../www/bower_components/chainpad-crypto");
 var Mailbox = Crypto.Mailbox;
-var Nacl = require("tweetnacl");
+var Nacl = require("tweetnacl/nacl-fast");
 var nThen = require("nthen");
 var Pinpad = require("../../www/common/pinpad");
 var Rpc = require("../../www/common/rpc");
diff --git a/storage/tasks.js b/storage/tasks.js
index 4db1c7642..2209b3d59 100644
--- a/storage/tasks.js
+++ b/storage/tasks.js
@@ -1,7 +1,7 @@
 var Fs = require("fs");
 var Fse = require("fs-extra");
 var Path = require("path");
-var nacl = require("tweetnacl");
+var nacl = require("tweetnacl/nacl-fast");
 var nThen = require("nthen");
 
 var Tasks = module.exports;
diff --git a/www/common/common-hash.js b/www/common/common-hash.js
index e59604136..fa9feb7e1 100644
--- a/www/common/common-hash.js
+++ b/www/common/common-hash.js
@@ -530,7 +530,7 @@ Version 1
 };
 
     if (typeof(module) !== 'undefined' && module.exports) {
-        module.exports = factory(require("./common-util"), require("chainpad-crypto"), require("tweetnacl"));
+        module.exports = factory(require("./common-util"), require("chainpad-crypto"), require("tweetnacl/nacl-fast"));
     } else if ((typeof(define) !== 'undefined' && define !== null) && (define.amd !== null)) {
         define([
             '/common/common-util.js',
diff --git a/www/common/rpc.js b/www/common/rpc.js
index cb7790602..53d969d3b 100644
--- a/www/common/rpc.js
+++ b/www/common/rpc.js
@@ -404,7 +404,7 @@ var factory = function (Util, Nacl) {
 };
 
     if (typeof(module) !== 'undefined' && module.exports) {
-        module.exports = factory(require("./common-util"), require("tweetnacl"));
+        module.exports = factory(require("./common-util"), require("tweetnacl/nacl-fast"));
     } else if ((typeof(define) !== 'undefined' && define !== null) && (define.amd !== null)) {
         define([
             '/common/common-util.js',