diff --git a/src/js/crypto/aes-batch-worker.js b/src/js/crypto/aes-batch-worker.js
index 7b67937..d8c95c4 100644
--- a/src/js/crypto/aes-batch-worker.js
+++ b/src/js/crypto/aes-batch-worker.js
@@ -20,7 +20,7 @@
 
 		var args = e.data,
 			output = null,
-			aes = new app.crypto.AesCCM(),
+			aes = new app.crypto.AesCCM(sjcl),
 			util = new app.crypto.Util(null, null);
 
 		if (args.type === 'encrypt' && args.list) {
diff --git a/src/js/crypto/aes-ccm.js b/src/js/crypto/aes-ccm.js
index 05cdc8f..d701c5f 100644
--- a/src/js/crypto/aes-ccm.js
+++ b/src/js/crypto/aes-ccm.js
@@ -1,7 +1,7 @@
 /**
  * A Wrapper for SJCL's authenticated AES-CCM encryption
  */
-app.crypto.AesCCM = function() {
+var AesCCM = function(sjcl) {
 	'use strict';
 
 	var adata = []; // authenticated data (empty by default)
@@ -47,4 +47,10 @@ app.crypto.AesCCM = function() {
 		return pt;
 	};
 
-};
\ No newline at end of file
+};
+
+if (typeof module !== 'undefined' && module.exports) {
+	module.exports = AesCCM;
+} else {
+	app.crypto.AesCCM = AesCCM;
+}
\ No newline at end of file
diff --git a/src/js/crypto/aes-worker.js b/src/js/crypto/aes-worker.js
index 2dacea0..6910822 100644
--- a/src/js/crypto/aes-worker.js
+++ b/src/js/crypto/aes-worker.js
@@ -19,7 +19,7 @@
 
 		var args = e.data,
 			output = null,
-			aes = new app.crypto.AesCCM();
+			aes = new app.crypto.AesCCM(sjcl);
 
 		if (args.type === 'encrypt' && args.plaintext && args.key && args.iv) {
 			// start encryption
diff --git a/src/js/crypto/crypto.js b/src/js/crypto/crypto.js
index 44fc804..5b06ee3 100644
--- a/src/js/crypto/crypto.js
+++ b/src/js/crypto/crypto.js
@@ -6,7 +6,7 @@ app.crypto.Crypto = function(window, util) {
 	'use strict';
 
 	var symmetricUserKey, // the user's secret key used to encrypt item-keys
-	aes = new app.crypto.AesCCM(); // use authenticated AES-CCM mode by default
+	aes = new app.crypto.AesCCM(sjcl); // use authenticated AES-CCM mode by default
 
 	/**
 	 * Initializes the crypto modules by fetching the user's
diff --git a/src/js/crypto/nacl-crypto.js b/src/js/crypto/nacl-crypto.js
index 64829cc..cbf4e4a 100644
--- a/src/js/crypto/nacl-crypto.js
+++ b/src/js/crypto/nacl-crypto.js
@@ -1,7 +1,7 @@
 /**
  * A Wrapper for NaCl's asymmetric/symmetric crypto
  */
-app.crypto.NaclCrypto = function() {
+var NaclCrypto = function(util) {
 	'use strict';
 
 	/**
@@ -13,8 +13,8 @@ app.crypto.NaclCrypto = function() {
 		} else {
 			var keys = nacl.crypto_box_keypair();
 			return {
-				boxPk: window.btoa(nacl.decode_latin1(keys.boxPk)),
-				boxSk: window.btoa(nacl.decode_latin1(keys.boxSk))
+				boxPk: util.str2Base64(nacl.decode_latin1(keys.boxPk)),
+				boxSk: util.str2Base64(nacl.decode_latin1(keys.boxSk))
 			};
 		}
 	};
@@ -29,14 +29,14 @@ app.crypto.NaclCrypto = function() {
 	this.asymmetricEncrypt = function(plaintext, recipientBoxPk, senderBoxSk) {
 		// convert to Uint8Array
 		var ptBuf = nacl.encode_utf8(plaintext);
-		var recipientBoxPkBuf = nacl.encode_latin1(window.atob(recipientBoxPk));
-		var senderBoxSkBuf = nacl.encode_latin1(window.atob(senderBoxSk));
+		var recipientBoxPkBuf = nacl.encode_latin1(util.base642Str(recipientBoxPk));
+		var senderBoxSkBuf = nacl.encode_latin1(util.base642Str(senderBoxSk));
 		// generate nonce
 		var nonce = nacl.crypto_secretbox_random_nonce();
 
 		var ct = nacl.crypto_box(ptBuf, nonce, recipientBoxPkBuf, senderBoxSkBuf);
-		var ctBase64 = window.btoa(nacl.decode_latin1(ct));
-		var nonceBase64 = window.btoa(nacl.decode_latin1(nonce));
+		var ctBase64 = util.str2Base64(nacl.decode_latin1(ct));
+		var nonceBase64 = util.str2Base64(nacl.decode_latin1(nonce));
 
 		return {
 			ct: ctBase64,
@@ -54,10 +54,10 @@ app.crypto.NaclCrypto = function() {
 	 */
 	this.asymmetricDecrypt = function(ciphertext, nonce, senderBoxPk, recipientBoxSk) {
 		// convert to Uint8Array
-		var ctBuf = nacl.encode_latin1(window.atob(ciphertext));
-		var nonceBuf = nacl.encode_latin1(window.atob(nonce));
-		var senderBoxPkBuf = nacl.encode_latin1(window.atob(senderBoxPk));
-		var recipientBoxSkBuf = nacl.encode_latin1(window.atob(recipientBoxSk));
+		var ctBuf = nacl.encode_latin1(util.base642Str(ciphertext));
+		var nonceBuf = nacl.encode_latin1(util.base642Str(nonce));
+		var senderBoxPkBuf = nacl.encode_latin1(util.base642Str(senderBoxPk));
+		var recipientBoxSkBuf = nacl.encode_latin1(util.base642Str(recipientBoxSk));
 
 		var pt = nacl.crypto_box_open(ctBuf, nonceBuf, senderBoxPkBuf, recipientBoxSkBuf);
 		var ptStr = nacl.decode_utf8(pt);
@@ -65,4 +65,10 @@ app.crypto.NaclCrypto = function() {
 		return ptStr;
 	};
 
-};
\ No newline at end of file
+};
+
+if (typeof module !== 'undefined' && module.exports) {
+	module.exports = NaclCrypto;
+} else {
+	app.crypto.NaclCrypto = NaclCrypto;
+}
\ No newline at end of file
diff --git a/src/js/crypto/util.js b/src/js/crypto/util.js
index bae431b..b538f11 100644
--- a/src/js/crypto/util.js
+++ b/src/js/crypto/util.js
@@ -172,6 +172,22 @@ var Util = function(window, uuid) {
 		return str;
 	};
 
+	/**
+	 * Converts a binary String (e.g. from the FileReader Api) to a UInt8Array
+	 * @param str [String] a binary string with integer values (0..255) per character
+	 * @return [UInt8Array]
+	 */
+	this.binStr2Uint8Arr = function(str) {
+		var c, buf = new Uint8Array(str.length);
+
+		for (var i = 0; i < buf.length; i++) {
+			c = str.charCodeAt(i);
+			buf[i] = (c & 0xff);
+		}
+
+		return buf;
+	};
+
 	/**
 	 * Convert a str to base64 in a browser and in node.js
 	 */
diff --git a/src/test/unit/aes-test.js b/src/test/unit/aes-test.js
index 18e87eb..cb2a0b8 100644
--- a/src/test/unit/aes-test.js
+++ b/src/test/unit/aes-test.js
@@ -29,15 +29,15 @@ test("CBC mode", 4, function() {
 });
 
 test("CCM mode", 2, function() {
-	var aes = new app.crypto.AesCCM();
-	
+	var aes = new app.crypto.AesCCM(sjcl);
+
 	var plaintext = aes_test.test_message;
 	var key = aes_test.util.random(aes_test.keySize);
 	var iv = aes_test.util.random(104);
-	
+
 	var ciphertext = aes.encrypt(plaintext, key, iv);
 	ok(ciphertext, 'Ciphertext length: ' + ciphertext.length);
-	
+
 	var decrypted = aes.decrypt(ciphertext, key, iv);
 	equal(decrypted, plaintext, 'Decryption correct: ' + decrypted);
 });
diff --git a/src/test/unit/nacl-crypto-test.js b/src/test/unit/nacl-crypto-test.js
index 52bb870..c952b4d 100644
--- a/src/test/unit/nacl-crypto-test.js
+++ b/src/test/unit/nacl-crypto-test.js
@@ -6,13 +6,19 @@ var nacl_test = {
 
 test("Init", 1, function() {
 	// init dependencies
-	nacl_test.util = new app.crypto.Util(window, uuid);
-	ok(nacl_test.util, 'Util');
+	var util = new app.crypto.Util(window, uuid);
+	ok(util, 'Util');
 	// generate test data
 	nacl_test.test_message = new TestData().generateBigString(1000);
-	nacl_test.crypto = new app.crypto.NaclCrypto();
+	nacl_test.crypto = new app.crypto.NaclCrypto(util);
 });
 
+// test("Generate Keypair from seed", 2, function() {
+// 	// generate keypair from seed
+// 	var keys = nacl_test.crypto.generateKeypair();
+// 	ok(keys.boxSk && keys.boxPk, "Keypair: " + JSON.stringify(keys));
+// });
+
 test("Generate Keypair", 2, function() {
 	// generate keypair from seed
 	var senderKeypair = nacl_test.crypto.generateKeypair();
diff --git a/src/test/unit/util-test.js b/src/test/unit/util-test.js
index d01f738..e00ef1c 100644
--- a/src/test/unit/util-test.js
+++ b/src/test/unit/util-test.js
@@ -1,13 +1,13 @@
 module("Util");
 
 test("JQuery and basic requirements", 7, function() {
-	ok( Array.prototype.push, "Array.push()" );
-	ok( Function.prototype.apply, "Function.apply()" );
-	ok( document.getElementById, "getElementById" );
-	ok( document.getElementsByTagName, "getElementsByTagName" );
-	ok( RegExp, "RegExp" );
-	ok( jQuery, "jQuery" );
-	ok( $, "$" );
+	ok(Array.prototype.push, "Array.push()");
+	ok(Function.prototype.apply, "Function.apply()");
+	ok(document.getElementById, "getElementById");
+	ok(document.getElementsByTagName, "getElementsByTagName");
+	ok(RegExp, "RegExp");
+	ok(jQuery, "jQuery");
+	ok($, "$");
 });
 
 test("UUID", 2, function() {
@@ -32,25 +32,15 @@ test("Parse Date", 1, function() {
 	ok(date, "Date: " + date);
 });
 
-test("String -> ArrayBuffer -> String", 3, function() {
+test("String -> Uint8Array -> String", 3, function() {
 	var util = new app.crypto.Util(window);
-	
+
 	var input = "asdf";
-	var buf = util.binStr2ArrBuf(input);
+	var buf = util.binStr2Uint8Arr(input);
 	ok(buf);
-	
+
 	// test slow conversion in js
-	var binStr = util.arrBuf2BinStr(buf);
+	var binStr = util.uint8Arr2BinStr(buf);
 	ok(binStr);
 	equal(binStr, input);
-	
-	// // test native conversion with BlobBuilder Api
-	// var blob = util.arrBuf2Blob(buf, 'application/octet-stream');
-	// ok(blob);
-	// 
-	// util.blob2BinStr(blob, function(output) {
-	// 	equal(output, input);
-	// 
-	// 	start();
-	// });
-});
+});
\ No newline at end of file