diff --git a/lib/deflate.js b/lib/deflate.js
index ffdd753..168e8cb 100644
--- a/lib/deflate.js
+++ b/lib/deflate.js
@@ -200,18 +200,18 @@ Deflate.prototype.push = function(data, mode) {
   // Convert data if needed
   if (typeof data === 'string') {
     // If we need to compress text, change encoding to utf8.
-    strm.next_in = strings.string2buf(data);
+    strm.input = strings.string2buf(data);
   } else {
-    strm.next_in = data;
+    strm.input = data;
   }
 
-  strm.next_in_index = 0;
-  strm.avail_in = strm.next_in.length;
+  strm.next_in = 0;
+  strm.avail_in = strm.input.length;
 
   do {
     if (strm.avail_out === 0) {
-      strm.next_out = new utils.Buf8(chunkSize);
-      strm.next_out_index = 0;
+      strm.output = new utils.Buf8(chunkSize);
+      strm.next_out = 0;
       strm.avail_out = chunkSize;
     }
     status = zlib_deflate.deflate(strm, _mode);    /* no bad return value */
@@ -223,9 +223,9 @@ Deflate.prototype.push = function(data, mode) {
     }
     if (strm.avail_out === 0 || (strm.avail_in === 0 && _mode === Z_FINISH)) {
       if (this.options.to === 'string') {
-        this.onData(strings.buf2binstring(utils.shrinkBuf(strm.next_out, strm.next_out_index)));
+        this.onData(strings.buf2binstring(utils.shrinkBuf(strm.output, strm.next_out)));
       } else {
-        this.onData(utils.shrinkBuf(strm.next_out, strm.next_out_index));
+        this.onData(utils.shrinkBuf(strm.output, strm.next_out));
       }
     }
   } while ((strm.avail_in > 0 || strm.avail_out === 0) && status !== Z_STREAM_END);
diff --git a/lib/inflate.js b/lib/inflate.js
index 3320c10..e960a10 100644
--- a/lib/inflate.js
+++ b/lib/inflate.js
@@ -175,7 +175,7 @@ Inflate.prototype.push = function(data, mode) {
   var strm = this.strm;
   var chunkSize = this.options.chunkSize;
   var status, _mode;
-  var next_out_utf8_index, tail, utf8str;
+  var next_out_utf8, tail, utf8str;
 
   if (this.ended) { return false; }
   _mode = (mode === ~~mode) ? mode : ((mode === true) ? c.Z_FINISH : c.Z_NO_FLUSH);
@@ -183,18 +183,18 @@ Inflate.prototype.push = function(data, mode) {
   // Convert data if needed
   if (typeof data === 'string') {
     // Only binary strings can be decompressed on practice
-    strm.next_in = strings.binstring2buf(data);
+    strm.input = strings.binstring2buf(data);
   } else {
-    strm.next_in = data;
+    strm.input = data;
   }
 
-  strm.next_in_index = 0;
-  strm.avail_in = strm.next_in.length;
+  strm.next_in = 0;
+  strm.avail_in = strm.input.length;
 
   do {
     if (strm.avail_out === 0) {
-      strm.next_out = new utils.Buf8(chunkSize);
-      strm.next_out_index = 0;
+      strm.output = new utils.Buf8(chunkSize);
+      strm.next_out = 0;
       strm.avail_out = chunkSize;
     }
 
@@ -206,25 +206,25 @@ Inflate.prototype.push = function(data, mode) {
       return false;
     }
 
-    if (strm.next_out_index) {
+    if (strm.next_out) {
       if (strm.avail_out === 0 || status === c.Z_STREAM_END || (strm.avail_in === 0 && _mode === c.Z_FINISH)) {
 
         if (this.options.to === 'string') {
 
-          next_out_utf8_index = strings.utf8border(strm.next_out, strm.next_out_index);
+          next_out_utf8 = strings.utf8border(strm.output, strm.next_out);
 
-          tail = strm.next_out_index - next_out_utf8_index;
-          utf8str = strings.buf2string(strm.next_out, next_out_utf8_index);
+          tail = strm.next_out - next_out_utf8;
+          utf8str = strings.buf2string(strm.output, next_out_utf8);
 
           // move tail
-          strm.next_out_index = tail;
+          strm.next_out = tail;
           strm.avail_out = chunkSize - tail;
-          if (tail) { utils.arraySet(strm.next_out, strm.next_out, next_out_utf8_index, tail, 0); }
+          if (tail) { utils.arraySet(strm.output, strm.output, next_out_utf8, tail, 0); }
 
           this.onData(utf8str);
 
         } else {
-          this.onData(utils.shrinkBuf(strm.next_out, strm.next_out_index));
+          this.onData(utils.shrinkBuf(strm.output, strm.next_out));
         }
       }
     }
diff --git a/lib/zlib/deflate.js b/lib/zlib/deflate.js
index b7b4188..b483cbb 100644
--- a/lib/zlib/deflate.js
+++ b/lib/zlib/deflate.js
@@ -118,7 +118,7 @@ function zero(buf) { var len = buf.length; while (--len >= 0) { buf[len] = 0; }
 /* =========================================================================
  * Flush as much pending output as possible. All deflate() output goes
  * through this function so some applications may wish to modify it
- * to avoid allocating a large strm->next_out buffer and copying into it.
+ * to avoid allocating a large strm->output buffer and copying into it.
  * (See also read_buf()).
  */
 function flush_pending(strm) {
@@ -131,8 +131,8 @@ function flush_pending(strm) {
   }
   if (len === 0) { return; }
 
-  utils.arraySet(strm.next_out, s.pending_buf, s.pending_out, len, strm.next_out_index);
-  strm.next_out_index += len;
+  utils.arraySet(strm.output, s.pending_buf, s.pending_out, len, strm.next_out);
+  strm.next_out += len;
   s.pending_out += len;
   strm.total_out += len;
   strm.avail_out -= len;
@@ -172,7 +172,7 @@ function putShortMSB(s, b) {
  * Read a new buffer from the current input stream, update the adler32
  * and total number of bytes read.  All deflate() input goes through
  * this function so some applications may wish to modify it to avoid
- * allocating a large strm->next_in buffer and copying from it.
+ * allocating a large strm->input buffer and copying from it.
  * (See also flush_pending()).
  */
 function read_buf(strm, buf, start, size) {
@@ -183,7 +183,7 @@ function read_buf(strm, buf, start, size) {
 
   strm.avail_in -= len;
 
-  utils.arraySet(buf, strm.next_in, strm.next_in_index, len, start);
+  utils.arraySet(buf, strm.input, strm.next_in, len, start);
   if (strm.state.wrap === 1) {
     strm.adler = adler32(strm.adler, buf, len, start);
   }
@@ -192,7 +192,7 @@ function read_buf(strm, buf, start, size) {
     strm.adler = crc32(strm.adler, buf, len, start);
   }
 
-  strm.next_in_index += len;
+  strm.next_in += len;
   strm.total_in += len;
 
   return len;
@@ -1391,8 +1391,8 @@ function deflate(strm, flush) {
 
   s = strm.state;
 
-  if (!strm.next_out ||
-      (!strm.next_in && strm.avail_in !== 0) ||
+  if (!strm.output ||
+      (!strm.input && strm.avail_in !== 0) ||
       (s.status === FINISH_STATE && flush !== Z_FINISH)) {
     return err(strm, (strm.avail_out === 0) ? Z_BUF_ERROR : Z_STREAM_ERROR);
   }
diff --git a/lib/zlib/inffast.js b/lib/zlib/inffast.js
index df0ae2f..1bcae7f 100644
--- a/lib/zlib/inffast.js
+++ b/lib/zlib/inffast.js
@@ -41,10 +41,10 @@ var TYPE = 12;      /* i: waiting for type bits, including last-flag bit */
  */
 module.exports = function inflate_fast(strm, start) {
   var state;
-  var _in;                    /* local strm.next_in */
+  var _in;                    /* local strm.input */
   var last;                   /* have enough input while in < last */
-  var _out;                   /* local strm.next_out */
-  var beg;                    /* inflate()'s initial strm.next_out */
+  var _out;                   /* local strm.output */
+  var beg;                    /* inflate()'s initial strm.output */
   var end;                    /* while out < end, enough space available */
 //#ifdef INFLATE_STRICT
   var dmax;                   /* maximum distance from zlib header */
@@ -73,11 +73,11 @@ module.exports = function inflate_fast(strm, start) {
   /* copy state to local variables */
   state = strm.state;
   //here = state.here;
-  _in = strm.next_in_index;
-  input = strm.next_in;
+  _in = strm.next_in;
+  input = strm.input;
   last = _in + (strm.avail_in - 5);
-  _out = strm.next_out_index;
-  output = strm.next_out;
+  _out = strm.next_out;
+  output = strm.output;
   beg = _out - (start - strm.avail_out);
   end = _out + (strm.avail_out - 257);
 //#ifdef INFLATE_STRICT
@@ -315,8 +315,8 @@ module.exports = function inflate_fast(strm, start) {
   hold &= (1 << bits) - 1;
 
   /* update state and return */
-  strm.next_in_index = _in;
-  strm.next_out_index = _out;
+  strm.next_in = _in;
+  strm.next_out = _out;
   strm.avail_in = (_in < last ? 5 + (last - _in) : 5 - (_in - last));
   strm.avail_out = (_out < end ? 257 + (end - _out) : 257 - (_out - end));
   state.hold = hold;
diff --git a/lib/zlib/inflate.js b/lib/zlib/inflate.js
index 79e3fd7..805f545 100644
--- a/lib/zlib/inflate.js
+++ b/lib/zlib/inflate.js
@@ -384,8 +384,8 @@ function inflate(strm, flush) {
     [16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15];
 
 
-  if (!strm || !strm.state || !strm.next_out ||
-      (!strm.next_in && strm.avail_in !== 0)) {
+  if (!strm || !strm.state || !strm.output ||
+      (!strm.input && strm.avail_in !== 0)) {
     return Z_STREAM_ERROR;
   }
 
@@ -394,11 +394,11 @@ function inflate(strm, flush) {
 
 
   //--- LOAD() ---
-  put = strm.next_out_index;
-  output = strm.next_out;
+  put = strm.next_out;
+  output = strm.output;
   left = strm.avail_out;
-  next = strm.next_in_index;
-  input = strm.next_in;
+  next = strm.next_in;
+  input = strm.input;
   have = strm.avail_in;
   hold = state.hold;
   bits = state.bits;
@@ -724,9 +724,9 @@ function inflate(strm, flush) {
     case DICT:
       if (state.havedict === 0) {
         //--- RESTORE() ---
-        strm.next_out_index = put;
+        strm.next_out = put;
         strm.avail_out = left;
-        strm.next_in_index = next;
+        strm.next_in = next;
         strm.avail_in = have;
         state.hold = hold;
         state.bits = bits;
@@ -1076,20 +1076,20 @@ function inflate(strm, flush) {
     case LEN:
       if (have >= 6 && left >= 258) {
         //--- RESTORE() ---
-        strm.next_out_index = put;
+        strm.next_out = put;
         strm.avail_out = left;
-        strm.next_in_index = next;
+        strm.next_in = next;
         strm.avail_in = have;
         state.hold = hold;
         state.bits = bits;
         //---
         inflate_fast(strm, _out);
         //--- LOAD() ---
-        put = strm.next_out_index;
-        output = strm.next_out;
+        put = strm.next_out;
+        output = strm.output;
         left = strm.avail_out;
-        next = strm.next_in_index;
-        input = strm.next_in;
+        next = strm.next_in;
+        input = strm.input;
         have = strm.avail_in;
         hold = state.hold;
         bits = state.bits;
@@ -1410,9 +1410,9 @@ function inflate(strm, flush) {
    */
 
   //--- RESTORE() ---
-  strm.next_out_index = put;
+  strm.next_out = put;
   strm.avail_out = left;
-  strm.next_in_index = next;
+  strm.next_in = next;
   strm.avail_in = have;
   state.hold = hold;
   state.bits = bits;
@@ -1420,7 +1420,7 @@ function inflate(strm, flush) {
 
   if (state.wsize || (_out !== strm.avail_out && state.mode < BAD &&
                       (state.mode < CHECK || flush !== Z_FINISH))) {
-    if (updatewindow(strm, strm.next_out, strm.next_out_index, _out - strm.avail_out)) {
+    if (updatewindow(strm, strm.output, strm.next_out, _out - strm.avail_out)) {
       state.mode = MEM;
       return Z_MEM_ERROR;
     }
@@ -1431,8 +1431,8 @@ function inflate(strm, flush) {
   strm.total_out += _out;
   state.total += _out;
   if (state.wrap && _out) {
-    strm.adler = state.check = /*UPDATE(state.check, strm.next_out_index - _out, _out);*/
-      (state.flags ? crc32(state.check, output, _out, strm.next_out_index - _out) : adler32(state.check, output, _out, strm.next_out_index - _out));
+    strm.adler = state.check = /*UPDATE(state.check, strm.next_out - _out, _out);*/
+      (state.flags ? crc32(state.check, output, _out, strm.next_out - _out) : adler32(state.check, output, _out, strm.next_out - _out));
   }
   strm.data_type = state.bits + (state.last ? 64 : 0) +
                     (state.mode === TYPE ? 128 : 0) +
diff --git a/lib/zlib/zstream.js b/lib/zlib/zstream.js
index d9d5265..928148b 100644
--- a/lib/zlib/zstream.js
+++ b/lib/zlib/zstream.js
@@ -3,16 +3,16 @@
 
 function ZStream() {
   /* next input byte */
-  this.next_in = null;
-  this.next_in_index = 0; // JS specific, offset in next_in
-  /* number of bytes available at next_in */
+  this.input = null;
+  this.next_in = 0; // JS specific, offset in input
+  /* number of bytes available at input */
   this.avail_in = 0;
   /* total number of input bytes read so far */
   this.total_in = 0;
   /* next output byte should be put there */
-  this.next_out = null;
-  this.next_out_index = 0; // JS specific, offset in next_out
-  /* remaining free space at next_out */
+  this.output = null;
+  this.next_out = 0; // JS specific, offset in output
+  /* remaining free space at output */
   this.avail_out = 0;
   /* total number of bytes output so far */
   this.total_out = 0;
diff --git a/test/gzip_specials.js b/test/gzip_specials.js
index 1c116bc..b3b4c95 100644
--- a/test/gzip_specials.js
+++ b/test/gzip_specials.js
@@ -75,7 +75,7 @@ describe('Gzip special cases', function() {
 
       assert(!inflator.err, inflator.msg);
 
-      pos += strm.next_in_index;
+      pos += strm.next_in;
       i++;
     } while (strm.avail_in);
 
diff --git a/test/inflate_cover_ported.js b/test/inflate_cover_ported.js
index 0eda02f..711d3ea 100644
--- a/test/inflate_cover_ported.js
+++ b/test/inflate_cover_ported.js
@@ -210,7 +210,7 @@ describe('Inflate support', function() {
     var ret;
     var strm = new zlib_stream();
     strm.avail_in = 0;
-    strm.next_in = null;
+    strm.input = null;
 
     ret = zlib_inflate.inflateInit(strm);
     assert(ret === c.Z_OK);