diff --git a/build-js.sh b/build-js.sh
index 53b042f..427501d 100755
--- a/build-js.sh
+++ b/build-js.sh
@@ -65,10 +65,11 @@ echo "building nntpchan.js ..."
 echo
 initfile "$outfile"
 
-
-for f in ./contrib/js/contrib/*.js ; do
-    mini "$f" "$outfile"
-done
+if [ -e ./contrib/js/contrib/*.js ] ; then
+    for f in ./contrib/js/contrib/*.js ; do
+        mini "$f" "$outfile"
+    done
+fi
 
 mini ./contrib/js/entry.js "$outfile"
 
diff --git a/contrib/js/contrib/chacha20.js b/contrib/js/contrib/chacha20.js
deleted file mode 100644
index e9247bd..0000000
--- a/contrib/js/contrib/chacha20.js
+++ /dev/null
@@ -1,116 +0,0 @@
-/* chacha20 - 256 bits */
-
-// Written in 2014 by Devi Mandiri. Public domain.
-//
-// Implementation derived from chacha-ref.c version 20080118
-// See for details: http://cr.yp.to/chacha/chacha-20080128.pdf
-
-function U8TO32_LE(x, i) {
-  return x[i] | (x[i+1]<<8) | (x[i+2]<<16) | (x[i+3]<<24);
-}
-
-function U32TO8_LE(x, i, u) {
-  x[i]   = u; u >>>= 8;
-  x[i+1] = u; u >>>= 8;
-  x[i+2] = u; u >>>= 8;
-  x[i+3] = u;
-}
-
-function ROTATE(v, c) {
-  return (v << c) | (v >>> (32 - c));
-}
-
-var Chacha20 = function(key, nonce, counter) {
-  this.input = new Uint32Array(16);
-
-  // https://tools.ietf.org/html/draft-irtf-cfrg-chacha20-poly1305-01#section-2.3
-  this.input[0] = 1634760805;
-  this.input[1] =  857760878;
-  this.input[2] = 2036477234;
-  this.input[3] = 1797285236;
-  this.input[4] = U8TO32_LE(key, 0);
-  this.input[5] = U8TO32_LE(key, 4);
-  this.input[6] = U8TO32_LE(key, 8);
-  this.input[7] = U8TO32_LE(key, 12);
-  this.input[8] = U8TO32_LE(key, 16);
-  this.input[9] = U8TO32_LE(key, 20);
-  this.input[10] = U8TO32_LE(key, 24);
-  this.input[11] = U8TO32_LE(key, 28);
-  // be compatible with the reference ChaCha depending on the nonce size
-  if(nonce.length == 12)
-  {
-    this.input[12] = counter;
-    this.input[13] = U8TO32_LE(nonce, 0);
-    this.input[14] = U8TO32_LE(nonce, 4);
-    this.input[15] = U8TO32_LE(nonce, 8);
-  }else{
-    this.input[12] = counter;
-    this.input[13] = 0;
-    this.input[14] = U8TO32_LE(nonce, 0);
-    this.input[15] = U8TO32_LE(nonce, 4);
-    
-  }
-};
-
-Chacha20.prototype.quarterRound = function(x, a, b, c, d) {
-  x[a] += x[b]; x[d] = ROTATE(x[d] ^ x[a], 16);
-  x[c] += x[d]; x[b] = ROTATE(x[b] ^ x[c], 12);
-  x[a] += x[b]; x[d] = ROTATE(x[d] ^ x[a],  8);
-  x[c] += x[d]; x[b] = ROTATE(x[b] ^ x[c],  7);
-};
-
-Chacha20.prototype.encrypt = function(dst, src, len) {
-  var x = new Uint32Array(16);
-  var output = new Uint8Array(64);
-  var i, dpos = 0, spos = 0;
-
-  while (len > 0 ) {
-    for (i = 16; i--;) x[i] = this.input[i];
-    for (i = 20; i > 0; i -= 2) {
-      this.quarterRound(x, 0, 4, 8,12);
-      this.quarterRound(x, 1, 5, 9,13);
-      this.quarterRound(x, 2, 6,10,14);
-      this.quarterRound(x, 3, 7,11,15);
-      this.quarterRound(x, 0, 5,10,15);
-      this.quarterRound(x, 1, 6,11,12);
-      this.quarterRound(x, 2, 7, 8,13);
-      this.quarterRound(x, 3, 4, 9,14);
-    }
-    for (i = 16; i--;) x[i] += this.input[i];
-    for (i = 16; i--;) U32TO8_LE(output, 4*i, x[i]);
-
-    this.input[12] += 1;
-    if (!this.input[12]) {
-      this.input[13] += 1;
-    }
-    if (len <= 64) {
-      for (i = len; i--;) {
-        dst[i+dpos] = src[i+spos] ^ output[i];
-      }
-      return;
-    }
-    for (i = 64; i--;) {
-      dst[i+dpos] = src[i+spos] ^ output[i];
-    }
-    len -= 64;
-    spos += 64;
-    dpos += 64;
-  }
-};
-
-Chacha20.prototype.keystream = function(dst, len) {
-  for (var i = 0; i < len; ++i) dst[i] = 0;
-  this.encrypt(dst, dst, len);
-};
-
-// additions to make it easier and export it as a module
-
-exports.Cipher = Chacha20;
-
-exports.encrypt = exports.decrypt = function(key, nonce, data)
-{
-  var cipher = new Chacha20(key, nonce);
-  var ret = new Buffer(data.length);
-  cipher.encrypt(ret, data, data.length);
-  return ret;
-}
\ No newline at end of file