diff --git a/src/datatypes/minecraft.js b/src/datatypes/minecraft.js
new file mode 100644
index 0000000..5907b2e
--- /dev/null
+++ b/src/datatypes/minecraft.js
@@ -0,0 +1,138 @@
+var nbt = require('prismarine-nbt');
+var utils = require("./utils");
+var numeric = require("./numeric");
+
+module.exports = {
+    'UUID': [readUUID, writeUUID, 16],
+    'position': [readPosition, writePosition, 8],
+    'slot': [readSlot, writeSlot, sizeOfSlot],
+    'nbt': [readNbt, utils.buffer[1], utils.buffer[2]]
+};
+
+function readUUID(buffer, offset) {
+    return {
+        value: [
+            buffer.readUInt32BE(offset),
+            buffer.readUInt32BE(offset + 4),
+            buffer.readUInt32BE(offset + 8),
+            buffer.readUInt32BE(offset + 12),
+        ],
+        size: 16,
+    };
+}
+
+function writeUUID(value, buffer, offset) {
+    buffer.writeUInt32BE(value[0], offset);
+    buffer.writeUInt32BE(value[1], offset + 4);
+    buffer.writeUInt32BE(value[2], offset + 8);
+    buffer.writeUInt32BE(value[3], offset + 12);
+    return offset + 16;
+}
+
+
+function readPosition(buffer, offset) {
+    var longVal = numeric.long[0](buffer, offset).value;
+    var x = signExtend26(longVal[0] >> 6);
+    var y = signExtend12(((longVal[0] & 0x3f) << 6) | ((longVal[1] >> 26) & 0x3f));
+    var z = signExtend26(longVal[1] & 0x3FFFFFF);
+    return {
+        value: { x: x, y: y, z: z },
+        size: 8
+    };
+}
+function signExtend26(value) {
+    if (value > 0x2000000) value -= 0x4000000;
+    return value;
+}
+function signExtend12(value) {
+    if (value > 0x800) value -= 0x1000;
+    return value;
+}
+
+
+function writePosition(value, buffer, offset) {
+    var longVal = [];
+    longVal[0] = ((value.x & 0x3FFFFFF) <<  6) | ((value.y & 0xFFF) >> 6);
+    longVal[1] = ((value.y & 0x3F) << 26) | (value.z & 0x3FFFFFF);
+    return numeric.long[1](longVal, buffer, offset);
+}
+
+
+function readSlot(buffer, offset) {
+    var value = {};
+    var results = numeric.short[0](buffer, offset);
+    if (! results) return null;
+    value.blockId = results.value;
+
+    if (value.blockId === -1) {
+        return {
+            value: value,
+            size: 2,
+        };
+    }
+
+    var cursorEnd = offset + 6;
+    if (cursorEnd > buffer.length) return null;
+    value.itemCount = buffer.readInt8(offset + 2);
+    value.itemDamage = buffer.readInt16BE(offset + 3);
+    var nbtData = buffer.readInt8(offset + 5);
+    if (nbtData == 0) {
+        return {
+            value: value,
+            size: 6
+        }
+    }
+    var nbtData = readNbt(buffer, offset + 5);
+    value.nbtData = nbtData.value;
+    return {
+        value: value,
+        size: nbtData.size + 5
+    };
+}
+
+function writeSlot(value, buffer, offset) {
+    buffer.writeInt16BE(value.blockId, offset);
+    if (value.blockId === -1) return offset + 2;
+    buffer.writeInt8(value.itemCount, offset + 2);
+    buffer.writeInt16BE(value.itemDamage, offset + 3);
+    var nbtDataLen;
+    if (value.nbtData)
+    {
+        var newbuf = nbt.writeUncompressed(value.nbtData);
+        newbuf.copy(buffer, offset + 5);
+        nbtDataLen = newbuf.length;
+    }
+    else
+    {
+        buffer.writeInt8(0, offset + 5);
+        nbtDataLen = 1;
+    }
+    return offset + 5 + nbtDataLen;
+}
+
+function sizeOfSlot(value) {
+    if (value.blockId === -1)
+        return (2);
+    else if (!value.nbtData) {
+        return (6);
+    } else {
+        return (5 + sizeOfNbt(value.nbtData));
+    }
+}
+
+
+function readNbt(buffer, offset) {
+    buffer = buffer.slice(offset);
+    return nbt.parseUncompressed(buffer);
+}
+
+function writeNbt(value, buffer, offset) {
+    var newbuf = nbt.writeUncompressed(value);
+    newbuf.copy(buffer, offset);
+    return offset + newbuf.length;
+}
+
+function sizeOfNbt(value) {
+    return nbt.writeUncompressed(value).length;
+}
+
diff --git a/src/protocol.js b/src/protocol.js
index d7fb5c4..d910435 100644
--- a/src/protocol.js
+++ b/src/protocol.js
@@ -1,7 +1,6 @@
 var assert = require('assert');
 var util = require('util');
 var zlib = require('zlib');
-var nbt = require('prismarine-nbt');
 
 var getField= require("./utils").getField;
 
@@ -53,6 +52,7 @@ var packetStates = {toClient: {}, toServer: {}};
 
 var numeric=require("./datatypes/numeric");
 var utils=require("./datatypes/utils");
+var minecraft=require("./datatypes/minecraft");
 
 var types = {
   'byte': numeric.byte,
@@ -66,17 +66,17 @@ var types = {
   'double': numeric.double,
   'bool': utils.bool,
   'string': utils.string,
-  'ustring': utils.ustring, // TODO : remove ustring
-  'UUID': [readUUID, writeUUID, 16],
+  'ustring': utils.ustring,
+  'UUID': minecraft.UUID,
   'container': [readContainer, writeContainer, sizeOfContainer],
   'array': [readArray, writeArray, sizeOfArray],
   'buffer': utils.buffer,
   'restBuffer': [readRestBuffer, utils.buffer[1], utils.buffer[2]],
   'count': [readCount, writeCount, sizeOfCount],
   // TODO : remove type-specific, replace with generic containers and arrays.
-  'position': [readPosition, writePosition, 8],
-  'slot': [readSlot, writeSlot, sizeOfSlot],
-  'nbt': [readNbt, utils.buffer[1], utils.buffer[2]],
+  'position': minecraft.position,
+  'slot': minecraft.slot,
+  'nbt': minecraft.nbt,
   'entityMetadata': [readEntityMetadata, writeEntityMetadata, sizeOfEntityMetadata],
   'condition': [readCondition, writeCondition, sizeOfCondition]
 };
@@ -154,184 +154,66 @@ function evalCondition(condition,field_values)
         return b;
 }
 
-function sizeOfEntityMetadata(value) {
-  var size = 1 + value.length;
-  var item;
-  for (var i = 0; i < value.length; ++i) {
-    item = value[i];
-    size += sizeOf(item.value, entityMetadataTypes[entityMetadataTypeBytes[item.type]], {});
-  }
-  return size;
-}
-
-function writeEntityMetadata(value, buffer, offset) {
-  value.forEach(function(item) {
-    var type = entityMetadataTypeBytes[item.type];
-    var headerByte = (type << 5) | item.key;
-    buffer.writeUInt8(headerByte, offset);
-    offset += 1;
-    offset = write(item.value, buffer, offset, entityMetadataTypes[type], {});
-  });
-  buffer.writeUInt8(0x7f, offset);
-  return offset + 1;
-}
-
-function writeUUID(value, buffer, offset) {
-  buffer.writeUInt32BE(value[0], offset);
-  buffer.writeUInt32BE(value[1], offset + 4);
-  buffer.writeUInt32BE(value[2], offset + 8);
-  buffer.writeUInt32BE(value[3], offset + 12);
-  return offset + 16;
-}
 
 function readEntityMetadata(buffer, offset) {
-  var cursor = offset;
-  var metadata = [];
-  var item, key, type, results, reader, typeName, dataType;
-  while (true) {
-    if (cursor + 1 > buffer.length) return null;
-    item = buffer.readUInt8(cursor);
-    cursor += 1;
-    if (item === 0x7f) {
-      return {
-        value: metadata,
-        size: cursor - offset,
-      };
+    var cursor = offset;
+    var metadata = [];
+    var item, key, type, results, reader, typeName, dataType;
+    while (true) {
+        if (cursor + 1 > buffer.length) return null;
+        item = buffer.readUInt8(cursor);
+        cursor += 1;
+        if (item === 0x7f) {
+            return {
+                value: metadata,
+                size: cursor - offset,
+            };
+        }
+        key = item & 0x1f;
+        type = item >> 5;
+        dataType = entityMetadataTypes[type];
+        typeName = dataType.type;
+        //debug("Reading entity metadata type " + dataType + " (" + ( typeName || "unknown" ) + ")");
+        if (!dataType) {
+            return {
+                error: new Error("unrecognized entity metadata type " + type)
+            }
+        }
+        results = read(buffer, cursor, dataType, {});
+        if (! results) return null;
+        metadata.push({
+            key: key,
+            value: results.value,
+            type: typeName,
+        });
+        cursor += results.size;
     }
-    key = item & 0x1f;
-    type = item >> 5;
-    dataType = entityMetadataTypes[type];
-    typeName = dataType.type;
-    //debug("Reading entity metadata type " + dataType + " (" + ( typeName || "unknown" ) + ")");
-    if (!dataType) {
-      return {
-        error: new Error("unrecognized entity metadata type " + type)
-      }
-    }
-    results = read(buffer, cursor, dataType, {});
-    if (! results) return null;
-    metadata.push({
-      key: key,
-      value: results.value,
-      type: typeName,
+}
+
+
+
+function writeEntityMetadata(value, buffer, offset) {
+    value.forEach(function(item) {
+        var type = entityMetadataTypeBytes[item.type];
+        var headerByte = (type << 5) | item.key;
+        buffer.writeUInt8(headerByte, offset);
+        offset += 1;
+        offset = write(item.value, buffer, offset, entityMetadataTypes[type], {});
     });
-    cursor += results.size;
-  }
+    buffer.writeUInt8(0x7f, offset);
+    return offset + 1;
 }
 
-function readNbt(buffer, offset) {
-  buffer = buffer.slice(offset);
-  return nbt.parseUncompressed(buffer);
-}
 
-function writeNbt(value, buffer, offset) {
-  var newbuf = nbt.writeUncompressed(value);
-  newbuf.copy(buffer, offset);
-  return offset + newbuf.length;
-}
 
-function sizeOfNbt(value) {
-  return nbt.writeUncompressed(value).length;
-}
-
-function readUUID(buffer, offset) {
-  return {
-    value: [
-      buffer.readUInt32BE(offset),
-      buffer.readUInt32BE(offset + 4),
-      buffer.readUInt32BE(offset + 8),
-      buffer.readUInt32BE(offset + 12),
-    ],
-    size: 16,
-  };
-}
-
-function readPosition(buffer, offset) {
-  var longVal = numeric.long[0](buffer, offset).value;
-  var x = signExtend26(longVal[0] >> 6);
-  var y = signExtend12(((longVal[0] & 0x3f) << 6) | ((longVal[1] >> 26) & 0x3f));
-  var z = signExtend26(longVal[1] & 0x3FFFFFF);
-  return {
-    value: { x: x, y: y, z: z },
-    size: 8
-  };
-}
-function signExtend26(value) {
-  if (value > 0x2000000) value -= 0x4000000;
-  return value;
-}
-function signExtend12(value) {
-  if (value > 0x800) value -= 0x1000;
-  return value;
-}
-
-function readSlot(buffer, offset) {
-  var value = {};
-  var results = numeric.short[0](buffer, offset);
-  if (! results) return null;
-  value.blockId = results.value;
-
-  if (value.blockId === -1) {
-    return {
-      value: value,
-      size: 2,
-    };
-  }
-
-  var cursorEnd = offset + 6;
-  if (cursorEnd > buffer.length) return null;
-  value.itemCount = buffer.readInt8(offset + 2);
-  value.itemDamage = buffer.readInt16BE(offset + 3);
-  var nbtData = buffer.readInt8(offset + 5);
-  if (nbtData == 0) {
-    return {
-      value: value,
-      size: 6
+function sizeOfEntityMetadata(value) {
+    var size = 1 + value.length;
+    var item;
+    for (var i = 0; i < value.length; ++i) {
+        item = value[i];
+        size += sizeOf(item.value, entityMetadataTypes[entityMetadataTypeBytes[item.type]], {});
     }
-  }
-  var nbtData = readNbt(buffer, offset + 5);
-  value.nbtData = nbtData.value;
-  return {
-    value: value,
-    size: nbtData.size + 5
-  };
-}
-
-function sizeOfSlot(value) {
-  if (value.blockId === -1)
-    return (2);
-  else if (!value.nbtData) {
-    return (6);
-  } else {
-    return (5 + sizeOfNbt(value.nbtData));
-  }
-}
-
-function writePosition(value, buffer, offset) {
-  var longVal = [];
-  longVal[0] = ((value.x & 0x3FFFFFF) <<  6) | ((value.y & 0xFFF) >> 6);
-  longVal[1] = ((value.y & 0x3F) << 26) | (value.z & 0x3FFFFFF);
-  return numeric.long[1](longVal, buffer, offset);
-}
-
-function writeSlot(value, buffer, offset) {
-  buffer.writeInt16BE(value.blockId, offset);
-  if (value.blockId === -1) return offset + 2;
-  buffer.writeInt8(value.itemCount, offset + 2);
-  buffer.writeInt16BE(value.itemDamage, offset + 3);
-  var nbtDataLen;
-  if (value.nbtData)
-  {
-    var newbuf = nbt.writeUncompressed(value.nbtData);
-    newbuf.copy(buffer, offset + 5);
-    nbtDataLen = newbuf.length;
-  }
-  else
-  {
-    buffer.writeInt8(0, offset + 5);
-    nbtDataLen = 1;
-  }
-  return offset + 5 + nbtDataLen;
+    return size;
 }