diff --git a/test/expected/serialize.json b/test/expected/serialize.json
new file mode 100644
index 0000000..2ef850d
--- /dev/null
+++ b/test/expected/serialize.json
@@ -0,0 +1,341 @@
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+}
\ No newline at end of file
diff --git a/test/expected/shape.json b/test/expected/shape.json
new file mode 100644
index 0000000..bffb8f0
--- /dev/null
+++ b/test/expected/shape.json
@@ -0,0 +1,1137 @@
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+              "y": 26
+            },
+            {
+              "face": 0,
+              "glyph": 68,
+              "x": 14,
+              "y": 26
+            },
+            {
+              "face": 0,
+              "glyph": 81,
+              "x": 27,
+              "y": 26
+            },
+            {
+              "face": 0,
+              "glyph": 82,
+              "x": 42,
+              "y": 26
+            },
+            {
+              "face": 0,
+              "glyph": 85,
+              "x": 57,
+              "y": 26
+            },
+            {
+              "face": 0,
+              "glyph": 68,
+              "x": 67,
+              "y": 26
+            },
+            {
+              "face": 0,
+              "glyph": 80,
+              "x": 80,
+              "y": 26
+            },
+            {
+              "face": 0,
+              "glyph": 76,
+              "x": 102,
+              "y": 26
+            },
+            {
+              "face": 0,
+              "glyph": 70,
+              "x": 108,
+              "y": 26
+            },
+            {
+              "face": 0,
+              "glyph": 3,
+              "x": 119,
+              "y": 26
+            },
+            {
+              "face": 0,
+              "glyph": 43,
+              "x": 125,
+              "y": 26
+            },
+            {
+              "face": 0,
+              "glyph": 90,
+              "x": 143,
+              "y": 26
+            },
+            {
+              "face": 0,
+              "glyph": 92,
+              "x": 162,
+              "y": 26
+            }
+          ],
+          "Shoreline Hwy": [
+            {
+              "face": 0,
+              "glyph": 54,
+              "x": 0,
+              "y": 26
+            },
+            {
+              "face": 0,
+              "glyph": 75,
+              "x": 13,
+              "y": 26
+            },
+            {
+              "face": 0,
+              "glyph": 82,
+              "x": 28,
+              "y": 26
+            },
+            {
+              "face": 0,
+              "glyph": 85,
+              "x": 43,
+              "y": 26
+            },
+            {
+              "face": 0,
+              "glyph": 72,
+              "x": 53,
+              "y": 26
+            },
+            {
+              "face": 0,
+              "glyph": 79,
+              "x": 66,
+              "y": 26
+            },
+            {
+              "face": 0,
+              "glyph": 76,
+              "x": 72,
+              "y": 26
+            },
+            {
+              "face": 0,
+              "glyph": 81,
+              "x": 78,
+              "y": 26
+            },
+            {
+              "face": 0,
+              "glyph": 72,
+              "x": 93,
+              "y": 26
+            },
+            {
+              "face": 0,
+              "glyph": 3,
+              "x": 106,
+              "y": 26
+            },
+            {
+              "face": 0,
+              "glyph": 43,
+              "x": 112,
+              "y": 26
+            },
+            {
+              "face": 0,
+              "glyph": 90,
+              "x": 130,
+              "y": 26
+            },
+            {
+              "face": 0,
+              "glyph": 92,
+              "x": 149,
+              "y": 26
+            }
+          ]
+        }
+      },
+      "faces": [
+        "Open Sans Regular"
+      ],
+      "_keys": [
+        "class",
+        "len",
+        "name",
+        "name_de",
+        "name_en",
+        "name_es",
+        "name_fr",
+        "osm_id",
+        "ref",
+        "reflen"
+      ],
+      "_values": [
+        "main",
+        7396.168723572097,
+        "Panoramic Hwy",
+        "Panoramic Highway",
+        88159974,
+        "",
+        0,
+        4357.193150547803,
+        "Shoreline Hwy",
+        "Shoreline Highway",
+        157338250,
+        3528.44005555027,
+        174215024,
+        2928.2679350617123,
+        125871918,
+        7600.032638046431,
+        12177319,
+        2513.4221036393283,
+        174215004,
+        1716.9016582189813,
+        12188378
+      ],
+      "_features": [
+        7198,
+        7359,
+        7455,
+        7904,
+        8088,
+        8845,
+        9146
+      ]
+    }
+  },
+  "faces": {
+    "Open Sans Regular": {
+      "glyphs": {
+        "3": {
+          "id": 3,
+          "width": 0,
+          "height": 0,
+          "left": 0,
+          "top": 0,
+          "advance": 6
+        },
+        "37": {
+          "id": 37,
+          "width": 13,
+          "height": 18,
+          "left": 2,
+          "top": 18,
+          "advance": 15
+        },
+        "43": {
+          "id": 43,
+          "width": 14,
+          "height": 18,
+          "left": 2,
+          "top": 18,
+          "advance": 17
+        },
+        "48": {
+          "id": 48,
+          "width": 18,
+          "height": 18,
+          "left": 2,
+          "top": 18,
+          "advance": 21
+        },
+        "49": {
+          "id": 49,
+          "width": 14,
+          "height": 18,
+          "left": 2,
+          "top": 18,
+          "advance": 18
+        },
+        "51": {
+          "id": 51,
+          "width": 12,
+          "height": 18,
+          "left": 2,
+          "top": 18,
+          "advance": 14
+        },
+        "54": {
+          "id": 54,
+          "width": 12,
+          "height": 19,
+          "left": 1,
+          "top": 18,
+          "advance": 13
+        },
+        "55": {
+          "id": 55,
+          "width": 14,
+          "height": 18,
+          "left": 0,
+          "top": 18,
+          "advance": 13
+        },
+        "57": {
+          "id": 57,
+          "width": 15,
+          "height": 18,
+          "left": 0,
+          "top": 18,
+          "advance": 14
+        },
+        "58": {
+          "id": 58,
+          "width": 22,
+          "height": 18,
+          "left": 0,
+          "top": 18,
+          "advance": 22
+        },
+        "68": {
+          "id": 68,
+          "width": 11,
+          "height": 15,
+          "left": 1,
+          "top": 14,
+          "advance": 13
+        },
+        "70": {
+          "id": 70,
+          "width": 10,
+          "height": 15,
+          "left": 1,
+          "top": 14,
+          "advance": 11
+        },
+        "71": {
+          "id": 71,
+          "width": 12,
+          "height": 20,
+          "left": 1,
+          "top": 19,
+          "advance": 14
+        },
+        "72": {
+          "id": 72,
+          "width": 12,
+          "height": 15,
+          "left": 1,
+          "top": 14,
+          "advance": 13
+        },
+        "75": {
+          "id": 75,
+          "width": 11,
+          "height": 19,
+          "left": 2,
+          "top": 19,
+          "advance": 14
+        },
+        "76": {
+          "id": 76,
+          "width": 4,
+          "height": 18,
+          "left": 1,
+          "top": 18,
+          "advance": 6
+        },
+        "79": {
+          "id": 79,
+          "width": 3,
+          "height": 19,
+          "left": 2,
+          "top": 19,
+          "advance": 6
+        },
+        "80": {
+          "id": 80,
+          "width": 19,
+          "height": 14,
+          "left": 2,
+          "top": 14,
+          "advance": 22
+        },
+        "81": {
+          "id": 81,
+          "width": 11,
+          "height": 14,
+          "left": 2,
+          "top": 14,
+          "advance": 14
+        },
+        "82": {
+          "id": 82,
+          "width": 13,
+          "height": 15,
+          "left": 1,
+          "top": 14,
+          "advance": 14
+        },
+        "83": {
+          "id": 83,
+          "width": 12,
+          "height": 20,
+          "left": 2,
+          "top": 14,
+          "advance": 14
+        },
+        "85": {
+          "id": 85,
+          "width": 8,
+          "height": 14,
+          "left": 2,
+          "top": 14,
+          "advance": 9
+        },
+        "86": {
+          "id": 86,
+          "width": 10,
+          "height": 15,
+          "left": 1,
+          "top": 14,
+          "advance": 11
+        },
+        "87": {
+          "id": 87,
+          "width": 8,
+          "height": 17,
+          "left": 0,
+          "top": 16,
+          "advance": 8
+        },
+        "88": {
+          "id": 88,
+          "width": 12,
+          "height": 14,
+          "left": 1,
+          "top": 13,
+          "advance": 14
+        },
+        "90": {
+          "id": 90,
+          "width": 19,
+          "height": 13,
+          "left": 0,
+          "top": 13,
+          "advance": 18
+        },
+        "92": {
+          "id": 92,
+          "width": 13,
+          "height": 19,
+          "left": 0,
+          "top": 13,
+          "advance": 12
+        }
+      },
+      "family": "Open Sans",
+      "style": "Regular"
+    }
+  }
+}
\ No newline at end of file
diff --git a/test/expected/simplify.json b/test/expected/simplify.json
new file mode 100644
index 0000000..ae98ad4
--- /dev/null
+++ b/test/expected/simplify.json
@@ -0,0 +1,337 @@
+{
+  "layers": {
+    "landuse": {
+      "version": 2,
+      "name": "landuse",
+      "extent": 4096,
+      "length": 3,
+      "shaping": {},
+      "faces": [],
+      "_keys": [
+        "class",
+        "osm_id"
+      ],
+      "_values": [
+        "park",
+        0,
+        0,
+        "sand",
+        0
+      ],
+      "_features": [
+        13,
+        223,
+        314
+      ]
+    },
+    "waterway": {
+      "version": 2,
+      "name": "waterway",
+      "extent": 4096,
+      "length": 11,
+      "shaping": {},
+      "faces": [],
+      "_keys": [
+        "osm_id",
+        "type"
+      ],
+      "_values": [
+        102639147,
+        "stream",
+        28483936,
+        28544165,
+        28544279,
+        28544488,
+        28544489,
+        28544658,
+        28544491,
+        28544660,
+        28544661,
+        28544659
+      ],
+      "_features": [
+        543,
+        616,
+        912,
+        960,
+        1036,
+        1133,
+        1180,
+        1221,
+        1259,
+        1285,
+        1344
+      ]
+    },
+    "water": {
+      "version": 2,
+      "name": "water",
+      "extent": 4096,
+      "length": 1,
+      "shaping": {},
+      "faces": [],
+      "_keys": [
+        "osm_id"
+      ],
+      "_values": [
+        0,
+        0,
+        0,
+        0,
+        0
+      ],
+      "_features": [
+        1542
+      ]
+    },
+    "road": {
+      "version": 2,
+      "name": "road",
+      "extent": 4096,
+      "length": 37,
+      "shaping": {},
+      "faces": [],
+      "_keys": [
+        "class",
+        "oneway",
+        "osm_id",
+        "type"
+      ],
+      "_values": [
+        "street_limited",
+        0,
+        12176014,
+        "residential",
+        "street",
+        102638413,
+        12190176,
+        125871922,
+        "unclassified",
+        12172969,
+        12171395,
+        12172974,
+        12171388,
+        12176906,
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+        12188141,
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+        112429240,
+        12172937,
+        12178793,
+        12184634,
+        12175654,
+        12187257,
+        12183699,
+        "main",
+        112926169,
+        "primary",
+        239213058,
+        174215004,
+        157338248,
+        174215024,
+        88159974,
+        "tertiary",
+        12177297,
+        12177319
+      ],
+      "_features": [
+        2190,
+        2312,
+        2407,
+        2441,
+        2555,
+        2624,
+        2658,
+        2691,
+        2769,
+        2797,
+        2830,
+        2858,
+        2895,
+        2932,
+        3002,
+        3033,
+        3155,
+        3215,
+        3258,
+        3289,
+        3334,
+        3403,
+        3448,
+        3477,
+        3507,
+        3560,
+        3610,
+        3645,
+        3677,
+        3711,
+        3889,
+        3947,
+        4069,
+        4358,
+        4399,
+        4707,
+        4746
+      ]
+    },
+    "bridge": {
+      "version": 2,
+      "name": "bridge",
+      "extent": 4096,
+      "length": 2,
+      "shaping": {},
+      "faces": [],
+      "_keys": [
+        "class",
+        "oneway",
+        "osm_id",
+        "type"
+      ],
+      "_values": [
+        "service",
+        0,
+        207142221,
+        "track",
+        "street",
+        207142175,
+        "residential"
+      ],
+      "_features": [
+        5511,
+        5540
+      ]
+    },
+    "place_label": {
+      "version": 2,
+      "name": "place_label",
+      "extent": 4096,
+      "length": 3,
+      "shaping": {},
+      "faces": [],
+      "_keys": [
+        "name",
+        "name_de",
+        "name_en",
+        "name_es",
+        "name_fr",
+        "osm_id",
+        "type",
+        "ldir",
+        "scalerank"
+      ],
+      "_values": [
+        "Mill Valley",
+        0,
+        "town",
+        "",
+        "Tamalpais Valley",
+        0,
+        0,
+        "hamlet",
+        "Muir Beach",
+        0
+      ],
+      "_features": [
+        5682,
+        5720,
+        5762
+      ]
+    },
+    "poi_label": {
+      "version": 2,
+      "name": "poi_label",
+      "extent": 4096,
+      "length": 1,
+      "shaping": {},
+      "faces": [],
+      "_keys": [
+        "localrank",
+        "maki",
+        "name",
+        "name_de",
+        "name_en",
+        "name_es",
+        "name_fr",
+        "osm_id",
+        "ref",
+        "scalerank",
+        "type"
+      ],
+      "_values": [
+        1,
+        "park",
+        "Muir Woods National Monument",
+        0,
+        "",
+        "Park"
+      ],
+      "_features": [
+        6010
+      ]
+    },
+    "road_label": {
+      "version": 2,
+      "name": "road_label",
+      "extent": 4096,
+      "length": 7,
+      "shaping": {},
+      "faces": [],
+      "_keys": [
+        "class",
+        "len",
+        "name",
+        "name_de",
+        "name_en",
+        "name_es",
+        "name_fr",
+        "osm_id",
+        "ref",
+        "reflen"
+      ],
+      "_values": [
+        "main",
+        7396.168723572097,
+        "Panoramic Hwy",
+        "Panoramic Highway",
+        88159974,
+        "",
+        0,
+        4357.193150547803,
+        "Shoreline Hwy",
+        "Shoreline Highway",
+        157338250,
+        3528.44005555027,
+        174215024,
+        2928.2679350617123,
+        125871918,
+        7600.032638046431,
+        12177319,
+        2513.4221036393283,
+        174215004,
+        1716.9016582189813,
+        12188378
+      ],
+      "_features": [
+        6226,
+        6387,
+        6483,
+        6932,
+        7116,
+        7873,
+        8174
+      ]
+    }
+  },
+  "faces": {}
+}
\ No newline at end of file
diff --git a/test/fixtures/mapbox-streets-v4.13.1306.3163.vector.pbf b/test/fixtures/mapbox-streets-v4.13.1306.3163.vector.pbf
new file mode 100644
index 0000000..a0d8c85
Binary files /dev/null and b/test/fixtures/mapbox-streets-v4.13.1306.3163.vector.pbf differ
diff --git a/test/format/ieee754.js b/test/format/ieee754.js
new file mode 100644
index 0000000..47d18da
--- /dev/null
+++ b/test/format/ieee754.js
@@ -0,0 +1,118 @@
+'use strict';
+
+// Copyright (c) 2008, Fair Oaks Labs, Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+//  * Redistributions of source code must retain the above copyright notice,
+//    this list of conditions and the following disclaimer.
+//
+//  * Redistributions in binary form must reproduce the above copyright notice,
+//    this list of conditions and the following disclaimer in the documentation
+//    and/or other materials provided with the distribution.
+//
+//  * Neither the name of Fair Oaks Labs, Inc. nor the names of its contributors
+//    may be used to endorse or promote products derived from this software
+//    without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+// ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+// POSSIBILITY OF SUCH DAMAGE.
+//
+//
+// Modifications to writeIEEE754 to support negative zeroes made by Brian White
+
+exports.readIEEE754 = function(buffer, offset, isBE, mLen, nBytes) {
+  var e, m,
+      eLen = nBytes * 8 - mLen - 1,
+      eMax = (1 << eLen) - 1,
+      eBias = eMax >> 1,
+      nBits = -7,
+      i = isBE ? 0 : (nBytes - 1),
+      d = isBE ? 1 : -1,
+      s = buffer[offset + i];
+
+  i += d;
+
+  e = s & ((1 << (-nBits)) - 1);
+  s >>= (-nBits);
+  nBits += eLen;
+  for (; nBits > 0; e = e * 256 + buffer[offset + i], i += d, nBits -= 8);
+
+  m = e & ((1 << (-nBits)) - 1);
+  e >>= (-nBits);
+  nBits += mLen;
+  for (; nBits > 0; m = m * 256 + buffer[offset + i], i += d, nBits -= 8);
+
+  if (e === 0) {
+    e = 1 - eBias;
+  } else if (e === eMax) {
+    return m ? NaN : ((s ? -1 : 1) * Infinity);
+  } else {
+    m = m + Math.pow(2, mLen);
+    e = e - eBias;
+  }
+  return (s ? -1 : 1) * m * Math.pow(2, e - mLen);
+};
+
+exports.writeIEEE754 = function(buffer, value, offset, isBE, mLen, nBytes) {
+  var e, m, c,
+      eLen = nBytes * 8 - mLen - 1,
+      eMax = (1 << eLen) - 1,
+      eBias = eMax >> 1,
+      rt = (mLen === 23 ? Math.pow(2, -24) - Math.pow(2, -77) : 0),
+      i = isBE ? (nBytes - 1) : 0,
+      d = isBE ? -1 : 1,
+      s = value < 0 || (value === 0 && 1 / value < 0) ? 1 : 0;
+
+  value = Math.abs(value);
+
+  if (isNaN(value) || value === Infinity) {
+    m = isNaN(value) ? 1 : 0;
+    e = eMax;
+  } else {
+    e = Math.floor(Math.log(value) / Math.LN2);
+    if (value * (c = Math.pow(2, -e)) < 1) {
+      e--;
+      c *= 2;
+    }
+    if (e + eBias >= 1) {
+      value += rt / c;
+    } else {
+      value += rt * Math.pow(2, 1 - eBias);
+    }
+    if (value * c >= 2) {
+      e++;
+      c /= 2;
+    }
+
+    if (e + eBias >= eMax) {
+      m = 0;
+      e = eMax;
+    } else if (e + eBias >= 1) {
+      m = (value * c - 1) * Math.pow(2, mLen);
+      e = e + eBias;
+    } else {
+      m = value * Math.pow(2, eBias - 1) * Math.pow(2, mLen);
+      e = 0;
+    }
+  }
+
+  for (; mLen >= 8; buffer[offset + i] = m & 0xff, i += d, m /= 256, mLen -= 8);
+
+  e = (e << mLen) | m;
+  eLen += mLen;
+  for (; eLen > 0; buffer[offset + i] = e & 0xff, i += d, e /= 256, eLen -= 8);
+
+  buffer[offset + i - d] |= s * 128;
+};
diff --git a/test/format/protobuf.js b/test/format/protobuf.js
new file mode 100644
index 0000000..c31a9e9
--- /dev/null
+++ b/test/format/protobuf.js
@@ -0,0 +1,116 @@
+'use strict';
+
+var ieee754 = require('./ieee754.js');
+
+module.exports = Protobuf;
+function Protobuf(buf) {
+    this.buf = buf;
+    this.length = buf.length;
+    this.pos = 0;
+}
+
+Protobuf.prototype.destroy = function() {
+    this.buf = null;
+};
+
+Protobuf.prototype.readUInt32 = function() {
+    var val = this.readUInt32LE(this.pos);
+    this.pos += 4;
+    return val;
+};
+
+Protobuf.prototype.readUInt64 = function() {
+    var val = this.readUInt64LE(this.pos);
+    this.pos += 8;
+    return val;
+};
+
+Protobuf.prototype.readDouble = function() {
+    var val = ieee754.readIEEE754(this.buf, this.pos, false, 52, 8);
+    this.pos += 8;
+    return val;
+};
+
+Protobuf.prototype.readVarint = function() {
+    // TODO: bounds checking
+    var pos = this.pos;
+    if (this.buf[pos] <= 0x7f) {
+        this.pos++;
+        return this.buf[pos];
+    } else if (this.buf[pos + 1] <= 0x7f) {
+        this.pos += 2;
+        return (this.buf[pos] & 0x7f) | (this.buf[pos + 1] << 7);
+    } else if (this.buf[pos + 2] <= 0x7f) {
+        this.pos += 3;
+        return (this.buf[pos] & 0x7f) | (this.buf[pos + 1] & 0x7f) << 7 | (this.buf[pos + 2]) << 14;
+    } else if (this.buf[pos + 3] <= 0x7f) {
+        this.pos += 4;
+        return (this.buf[pos] & 0x7f) | (this.buf[pos + 1] & 0x7f) << 7 | (this.buf[pos + 2] & 0x7f) << 14 | (this.buf[pos + 3]) << 21;
+    } else if (this.buf[pos + 4] <= 0x7f) {
+        this.pos += 5;
+        return ((this.buf[pos] & 0x7f) | (this.buf[pos + 1] & 0x7f) << 7 | (this.buf[pos + 2] & 0x7f) << 14 | (this.buf[pos + 3]) << 21) + (this.buf[pos + 4] * 268435456);
+    } else {
+        this.skip(0);
+        return 0;
+        // throw new Error("TODO: Handle 6+ byte varints");
+    }
+};
+
+Protobuf.prototype.readSVarint = function() {
+    var num = this.readVarint();
+    if (num > 2147483647) throw new Error('TODO: Handle numbers >= 2^30');
+    // zigzag encoding
+    return ((num >> 1) ^ -(num & 1));
+};
+
+Protobuf.prototype.readString = function() {
+    var bytes = this.readVarint();
+    // TODO: bounds checking
+    var chr = String.fromCharCode;
+    var b = this.buf;
+    var p = this.pos;
+    var end = this.pos + bytes;
+    var str = '';
+    while (p < end) {
+        if (b[p] <= 0x7F) str += chr(b[p++]);
+        else if (b[p] <= 0xBF) throw new Error('Invalid UTF-8 codepoint: ' + b[p]);
+        else if (b[p] <= 0xDF) str += chr((b[p++] & 0x1F) << 6 | (b[p++] & 0x3F));
+        else if (b[p] <= 0xEF) str += chr((b[p++] & 0x1F) << 12 | (b[p++] & 0x3F) << 6 | (b[p++] & 0x3F));
+        else if (b[p] <= 0xF7) p += 4; // We can't handle these codepoints in JS, so skip.
+        else if (b[p] <= 0xFB) p += 5;
+        else if (b[p] <= 0xFD) p += 6;
+        else throw new Error('Invalid UTF-8 codepoint: ' + b[p]);
+    }
+    this.pos += bytes;
+    return str;
+};
+
+Protobuf.prototype.readBuffer = function() {
+    var bytes = this.readVarint();
+    var buffer = this.buf.subarray(this.pos, this.pos + bytes);
+    this.pos += bytes;
+    return buffer;
+};
+
+Protobuf.prototype.readPacked = function(type) {
+    // TODO: bounds checking
+    var bytes = this.readVarint();
+    var end = this.pos + bytes;
+    var array = [];
+    while (this.pos < end) {
+        array.push(this['read' + type]());
+    }
+    return array;
+};
+
+Protobuf.prototype.skip = function(val) {
+    // TODO: bounds checking
+    var type = val & 0x7;
+    switch (type) {
+        /* varint */ case 0: while (this.buf[this.pos++] > 0x7f); break;
+        /* 64 bit */ case 1: this.pos += 8; break;
+        /* length */ case 2: var bytes = this.readVarint(); this.pos += bytes; break;
+        /* 32 bit */ case 5: this.pos += 4; break;
+        default: throw new Error('Unimplemented type: ' + type);
+    }
+};
diff --git a/test/format/vectortile.js b/test/format/vectortile.js
new file mode 100644
index 0000000..fd0fd5e
--- /dev/null
+++ b/test/format/vectortile.js
@@ -0,0 +1,102 @@
+'use strict';
+
+var VectorTileLayer = require('./vectortilelayer');
+
+module.exports = VectorTile;
+function VectorTile(buffer, end) {
+    // Public
+    this.layers = {};
+    this.faces = {};
+
+    // Private
+    this._buffer = buffer;
+
+    var val, tag;
+    if (typeof end === 'undefined') end = buffer.length;
+    while (buffer.pos < end) {
+        val = buffer.readVarint();
+        tag = val >> 3;
+        if (tag == 3) {
+            var layer = this.readLayer();
+            if (layer.length) {
+                this.layers[layer.name] = layer;
+            }
+        } else if (tag == 4) {
+            var face = this.readFace();
+            this.faces[face.family + ' ' + face.style] = face;
+        } else {
+            // console.warn('skipping tile tag ' + tag);
+            buffer.skip(val);
+        }
+    }
+}
+
+VectorTile.prototype.readLayer = function() {
+    var buffer = this._buffer;
+
+    var bytes = buffer.readVarint();
+    var end = buffer.pos + bytes;
+    var layer = new VectorTileLayer(buffer, end);
+    buffer.pos = end;
+    return layer;
+};
+
+VectorTile.prototype.readFace = function() {
+    var buffer = this._buffer;
+    var face = { glyphs: {} };
+
+    var bytes = buffer.readVarint();
+    var val, tag;
+    var end = buffer.pos + bytes;
+    while (buffer.pos < end) {
+        val = buffer.readVarint();
+        tag = val >> 3;
+
+        if (tag == 1) {
+            face.family = buffer.readString();
+        } else if (tag == 2) {
+            face.style = buffer.readString();
+        } else if (tag == 5) {
+            var glyph = this.readGlyph();
+            face.glyphs[glyph.id] = glyph;
+        } else {
+            buffer.skip(val);
+        }
+    }
+
+    return face;
+};
+
+
+VectorTile.prototype.readGlyph = function() {
+    var buffer = this._buffer;
+    var glyph = {};
+
+    var bytes = buffer.readVarint();
+    var val, tag;
+    var end = buffer.pos + bytes;
+    while (buffer.pos < end) {
+        val = buffer.readVarint();
+        tag = val >> 3;
+
+        if (tag == 1) {
+            glyph.id = buffer.readVarint();
+        } else if (tag == 2) {
+            glyph.bitmap = buffer.readBuffer();
+        } else if (tag == 3) {
+            glyph.width = buffer.readVarint();
+        } else if (tag == 4) {
+            glyph.height = buffer.readVarint();
+        } else if (tag == 5) {
+            glyph.left = buffer.readSVarint();
+        } else if (tag == 6) {
+            glyph.top = buffer.readSVarint();
+        } else if (tag == 7) {
+            glyph.advance = buffer.readVarint();
+        } else {
+            buffer.skip(val);
+        }
+    }
+
+    return glyph;
+};
diff --git a/test/format/vectortilefeature.js b/test/format/vectortilefeature.js
new file mode 100644
index 0000000..4691f43
--- /dev/null
+++ b/test/format/vectortilefeature.js
@@ -0,0 +1,145 @@
+'use strict';
+
+var VectorTilePoint = require('./vectortilepoint.js');
+
+/*
+ * Construct a new vector tile feature given a buffer.
+ *
+ * @param {object} buffer
+ * @param {number} [end]
+ * @param {extent}
+ * @param {object} keys
+ * @param {object} values
+ */
+module.exports = VectorTileFeature;
+function VectorTileFeature(buffer, end, extent, keys, values) {
+    // Public
+    this._extent = extent;
+    this._type = 0;
+
+    // Private
+    this._buffer = buffer;
+    this._geometry = -1;
+
+    if (typeof end === 'undefined') {
+        end = buffer.length;
+    }
+
+    var val, tag;
+    while (buffer.pos < end) {
+        val = buffer.readVarint();
+        tag = val >> 3;
+
+        if (tag == 1) {
+            this._id = buffer.readVarint();
+        } else if (tag == 2) {
+            var tag_end = buffer.pos + buffer.readVarint();
+            while (buffer.pos < tag_end) {
+                var key = keys[buffer.readVarint()];
+                var value = values[buffer.readVarint()];
+                this[key] = value;
+            }
+        } else if (tag == 3) {
+            this._type = buffer.readVarint();
+        } else if (tag == 4) {
+            this._geometry = buffer.pos;
+            buffer.skip(val);
+        } else {
+            buffer.skip(val);
+        }
+    }
+}
+
+VectorTileFeature.Unknown = 0;
+VectorTileFeature.Point = 1;
+VectorTileFeature.LineString = 2;
+VectorTileFeature.Polygon = 3;
+
+
+VectorTileFeature.mapping = [];
+VectorTileFeature.mapping[VectorTileFeature.Point] = 'point';
+VectorTileFeature.mapping[VectorTileFeature.LineString] = 'line';
+VectorTileFeature.mapping[VectorTileFeature.Polygon] = 'fill';
+
+
+VectorTileFeature.prototype.loadGeometry = function() {
+    var buffer = this._buffer;
+    buffer.pos = this._geometry;
+
+    var bytes = buffer.readVarint();
+    var end = buffer.pos + bytes;
+    var cmd = 1, length = 0, x = 0, y = 0;
+
+    var lines = [];
+    var line = null;
+
+    while (buffer.pos < end) {
+        if (!length) {
+            var cmd_length = buffer.readVarint();
+            cmd = cmd_length & 0x7;
+            length = cmd_length >> 3;
+        }
+
+        length--;
+
+        if (cmd == 1 || cmd == 2) {
+            x += buffer.readSVarint();
+            y += buffer.readSVarint();
+
+            if (cmd == 1) {
+                // moveTo
+                if (line) {
+                    lines.push(line);
+                }
+                line = [];
+            }
+
+            line.push(new VectorTilePoint(x, y));
+        } else if (cmd == 7) {
+            // closePolygon
+            line.push(line[0]);
+        } else {
+            throw new Error('unknown command ' + cmd);
+        }
+    }
+
+    if (line) {
+        lines.push(line);
+    }
+
+    return lines;
+};
+
+VectorTileFeature.prototype.bbox = function() {
+    var buffer = this._buffer;
+    buffer.pos = this._geometry;
+
+    var bytes = buffer.readVarint();
+    var end = buffer.pos + bytes;
+    var cmd = 1, length = 0, x = 0, y = 0;
+
+    var x1 = Infinity, x2 = -Infinity, y1 = Infinity, y2 = -Infinity;
+
+    while (buffer.pos < end) {
+        if (!length) {
+            var cmd_length = buffer.readVarint();
+            cmd = cmd_length & 0x7;
+            length = cmd_length >> 3;
+        }
+
+        length--;
+
+        if (cmd == 1 || cmd == 2) {
+            x += buffer.readSVarint();
+            y += buffer.readSVarint();
+            if (x < x1) x1 = x;
+            if (x > x2) x2 = x;
+            if (y < y1) y1 = y;
+            if (y > y2) y2 = y;
+        } else if (cmd != 7) {
+            throw new Error('unknown command ' + cmd);
+        }
+    }
+
+    return { x1: x1, y1: y1, x2: x2, y2: y2 };
+};
diff --git a/test/format/vectortilelayer.js b/test/format/vectortilelayer.js
new file mode 100644
index 0000000..76b0520
--- /dev/null
+++ b/test/format/vectortilelayer.js
@@ -0,0 +1,150 @@
+'use strict';
+
+var VectorTileFeature = require('./vectortilefeature.js');
+
+module.exports = VectorTileLayer;
+function VectorTileLayer(buffer, end) {
+    // Public
+    this.version = 1;
+    this.name = null;
+    this.extent = 4096;
+    this.length = 0;
+    this.shaping = {};
+    this.faces = [];
+
+    // Private
+    this._buffer = buffer;
+    this._keys = [];
+    this._values = [];
+    this._features = [];
+
+    var stack_index = [];
+    var labels = [];
+
+    var val, tag;
+    if (typeof end === 'undefined') end = buffer.length;
+    while (buffer.pos < end) {
+        val = buffer.readVarint();
+        tag = val >> 3;
+        if (tag == 15) {
+            this.version = buffer.readVarint();
+        } else if (tag == 1) {
+            this.name = buffer.readString();
+        } else if (tag == 5) {
+            this.extent = buffer.readVarint();
+        } else if (tag == 2) {
+            this.length++;
+            this._features.push(buffer.pos);
+            buffer.skip(val);
+        } else if (tag == 3) {
+            this._keys.push(buffer.readString());
+        } else if (tag == 4) {
+            this._values.push(this.readFeatureValue());
+        } else if (tag == 7) {
+            this.faces.push(buffer.readString());
+        } else if (tag == 8) {
+            labels.push(this.readLabel());
+        } else if (tag == 9) {
+            stack_index.push(buffer.readString());
+        } else {
+            console.warn('skipping layer tag ' + tag);
+            buffer.skip(val);
+        }
+    }
+
+    // Build index of [stack][text] => shaping information
+    var shaping = this.shaping;
+    for (var i = 0; i < labels.length; i++) {
+        var label = labels[i];
+        var text = this._values[label.text];
+        var stack = stack_index[label.stack];
+
+        if (!(stack in shaping)) shaping[stack] = {};
+        shaping[stack][text] = label.glyphs;
+    }
+}
+
+VectorTileLayer.prototype.readFeatureValue = function() {
+    var buffer = this._buffer;
+    var value = null;
+
+    var bytes = buffer.readVarint();
+    var val, tag;
+    var end = buffer.pos + bytes;
+    while (buffer.pos < end) {
+        val = buffer.readVarint();
+        tag = val >> 3;
+
+        if (tag == 1) {
+            value = buffer.readString();
+        } else if (tag == 2) {
+            throw new Error('read float');
+        } else if (tag == 3) {
+            value = buffer.readDouble();
+        } else if (tag == 4) {
+            value = buffer.readVarint();
+        } else if (tag == 5) {
+            throw new Error('read uint');
+        } else if (tag == 6) {
+            value = buffer.readSVarint();
+        } else if (tag == 7) {
+            value = Boolean(buffer.readVarint());
+        } else {
+            buffer.skip(val);
+        }
+    }
+
+    return value;
+};
+
+VectorTileLayer.prototype.readLabel = function() {
+    var label = { glyphs: [] };
+    var faces, glyphs, x, y;
+
+    var buffer = this._buffer;
+    var bytes = buffer.readVarint();
+    var val, tag;
+    var end = buffer.pos + bytes;
+    while (buffer.pos < end) {
+        val = buffer.readVarint();
+        tag = val >> 3;
+
+        if (tag == 1) {
+            label.text = buffer.readVarint();
+        } else if (tag == 2) {
+            label.stack = buffer.readVarint();
+        } else if (tag == 3) {
+            faces = buffer.readPacked('Varint');
+        } else if (tag == 4) {
+            glyphs = buffer.readPacked('Varint');
+        } else if (tag == 5) {
+            x = buffer.readPacked('Varint');
+        } else if (tag == 6) {
+            y = buffer.readPacked('Varint');
+        } else {
+            buffer.skip(val);
+        }
+    }
+
+    for (var i = 0; i < glyphs.length; i++) {
+        label.glyphs.push({ face: faces[i], glyph: glyphs[i], x: x[i], y: y[i] });
+    }
+
+    return label;
+};
+
+/*
+ * Return feature `i` from this layer as a `VectorTileFeature`
+ *
+ * @param {number} i
+ * @returns {VectorTileFeature}
+ */
+VectorTileLayer.prototype.feature = function(i) {
+    if (i < 0 || i >= this._features.length) {
+        throw new Error('feature index out of bounds');
+    }
+
+    this._buffer.pos = this._features[i];
+    var end = this._buffer.readVarint() + this._buffer.pos;
+    return new VectorTileFeature(this._buffer, end, this.extent, this._keys, this._values);
+};
diff --git a/test/format/vectortilepoint.js b/test/format/vectortilepoint.js
new file mode 100644
index 0000000..dd0797b
--- /dev/null
+++ b/test/format/vectortilepoint.js
@@ -0,0 +1,11 @@
+'use strict';
+
+module.exports = VectorTilePoint;
+function VectorTilePoint(x, y) {
+    this.x = x;
+    this.y = y;
+}
+
+VectorTilePoint.prototype.toString = function() {
+    return "Point(" + this.x + ", " + this.y + ")";
+};
diff --git a/test/test.js b/test/test.js
new file mode 100644
index 0000000..7d4b776
--- /dev/null
+++ b/test/test.js
@@ -0,0 +1,88 @@
+var fontserver = require('../index.js');
+var assert = require('assert');
+var zlib = require('zlib');
+var fs = require('fs');
+var zdata = fs.readFileSync(__dirname + '/fixtures/mapbox-streets-v4.13.1306.3163.vector.pbf');
+var Protobuf = require('./format/protobuf');
+var VectorTile = require('./format/vectortile');
+
+function nobuffer(key, val) {
+    return key !== '_buffer' && key !== 'bitmap' ? val : undefined;
+}
+
+function jsonEqual(key, json) {
+    fs.writeFileSync(__dirname + '/expected/'+key+'.json', JSON.stringify(json, null, 2));
+    assert.deepEqual(json, require('./expected/'+key+'.json'));
+}
+
+describe('convert', function() {
+    var data;
+    before(function(done) {
+        zlib.inflate(zdata, function(err, d) {
+            assert.ifError(err);
+            data = d;
+            done();
+        });
+    });
+
+    it('serialize', function(done) {
+        var tile = new fontserver.Tile(data);
+        var vt = new VectorTile(new Protobuf(new Uint8Array(tile.serialize())));
+        var json = JSON.parse(JSON.stringify(vt, nobuffer));
+        jsonEqual('serialize', json);
+        done();
+    });
+
+    it('simplify', function(done) {
+        var tile = new fontserver.Tile(data);
+        tile.simplify(function(err) {
+            assert.ifError(err);
+            var vt = new VectorTile(new Protobuf(new Uint8Array(tile.serialize())));
+            var json = JSON.parse(JSON.stringify(vt, nobuffer));
+            jsonEqual('simplify', json);
+            done();
+        });
+    });
+
+    it('simplify (x10)', function(done) {
+        this.timeout(10000);
+        var remaining = 10;
+        for (var i = 0; i < 10; i++) (function() {
+            var tile = new fontserver.Tile(data);
+            tile.simplify(function(err) {
+                assert.ifError(err);
+                var vt = new VectorTile(new Protobuf(new Uint8Array(tile.serialize())));
+                var json = JSON.parse(JSON.stringify(vt, nobuffer));
+                jsonEqual('simplify', json);
+                if (!--remaining) return done();
+            });
+        })();
+    });
+
+    it('shape', function(done) {
+        var tile = new fontserver.Tile(data);
+        tile.shape('Open Sans', function(err) {
+            assert.ifError(err);
+            var vt = new VectorTile(new Protobuf(new Uint8Array(tile.serialize())));
+            var json = JSON.parse(JSON.stringify(vt, nobuffer));
+            jsonEqual('shape', json);
+            done();
+        });
+    });
+
+    it('shape (x10)', function(done) {
+        this.timeout(10000);
+        var remaining = 10;
+        for (var i = 0; i < 10; i++) (function() {
+            var tile = new fontserver.Tile(data);
+            tile.shape('Open Sans', function(err) {
+                assert.ifError(err);
+                var vt = new VectorTile(new Protobuf(new Uint8Array(tile.serialize())));
+                var json = JSON.parse(JSON.stringify(vt, nobuffer));
+                jsonEqual('shape', json);
+                if (!--remaining) return done();
+            });
+        })();
+    });
+});
+