Merge branch 'master' into libuv-0.10-headless-display

Conflicts:
	common/curl_request.cpp
	common/glfw_view.cpp
	common/glfw_view.hpp
	include/mbgl/platform/request.hpp
	ios/mapbox-gl-cocoa
	setup-libraries.sh
	src/map/map.cpp
	src/platform/request.cpp
	test/fixtures/fixture_request.cpp

51 files changed, 1011 insertions, 252 deletions

diff --git a/include/mbgl/map/map.hpp b/include/mbgl/map/map.hpp
index ac33dba0ef..7e4687ea6f 100644
--- a/include/mbgl/map/map.hpp
+++ b/include/mbgl/map/map.hpp
@@ -7,11 +7,11 @@
 #include <mbgl/util/noncopyable.hpp>
 #include <mbgl/util/time.hpp>
 #include <mbgl/util/uv.hpp>
+#include <mbgl/util/ptr.hpp>
 
 #include <cstdint>
 #include <atomic>
 #include <iosfwd>
-#include <memory>
 #include <set>
 #include <vector>
 
@@ -31,21 +31,31 @@ class FileSource;
 class View;
 
 class Map : private util::noncopyable {
+    typedef void (*stop_callback)(void *);
+
 public:
     explicit Map(View &view);
     ~Map();
 
-    // Start/stop the map render thread
+    // Start the map render thread. It is asynchronous.
     void start();
-    void stop();
 
-    // Runs the map event loop.
+    // Stop the map render thread. This call will block until the map rendering thread stopped.
+    // The optional callback function will be invoked repeatedly until the map thread is stopped.
+    // The callback function should wait until it is woken up again by view.notify(), otherwise
+    // this will be a busy waiting loop. The optional data parameter will be passed to the callback
+    // function.
+    void stop(stop_callback cb = nullptr, void *data = nullptr);
+
+    // Runs the map event loop. ONLY run this function when you want to get render a single frame
+    // with this map object. It will *not* spawn a separate thread and instead block until the
+    // frame is completely rendered.
     void run();
 
     // Triggers a lazy rerender: only performs a render when the map is not clean.
     void rerender();
 
-    void renderLayer(std::shared_ptr<StyleLayer> layer_desc, RenderPass pass, const Tile::ID* id = nullptr, const mat4* matrix = nullptr);
+    void renderLayer(util::ptr<StyleLayer> layer_desc, RenderPass pass, const Tile::ID* id = nullptr, const mat4* matrix = nullptr);
 
     // Forces a map update: always triggers a rerender.
     void update();
@@ -65,7 +75,7 @@ public:
     void resize(uint16_t width, uint16_t height, float ratio, uint16_t fb_width, uint16_t fb_height);
 
     // Styling
-    const std::set<std::shared_ptr<StyleSource>> getActiveSources() const;
+    const std::set<util::ptr<StyleSource>> getActiveSources() const;
     void setAppliedClasses(const std::vector<std::string> &classes);
     void toggleClass(const std::string &name);
     const std::vector<std::string> &getAppliedClasses() const;
@@ -116,16 +126,20 @@ public:
     void toggleDebug();
     bool getDebug() const;
 
+    // Call this when the network reachability changed.
+    void setReachability(bool status);
+
 public:
     inline const TransformState &getState() const { return state; }
-    inline std::shared_ptr<FileSource> getFileSource() const { return fileSource; }
-    inline std::shared_ptr<Style> getStyle() const { return style; }
-    inline std::shared_ptr<GlyphAtlas> getGlyphAtlas() { return glyphAtlas; }
-    inline std::shared_ptr<GlyphStore> getGlyphStore() { return glyphStore; }
-    inline std::shared_ptr<SpriteAtlas> getSpriteAtlas() { return spriteAtlas; }
-    std::shared_ptr<Sprite> getSprite();
-    inline std::shared_ptr<Texturepool> getTexturepool() { return texturepool; }
-    inline std::shared_ptr<uv::loop> getLoop() { return loop; }
+    inline util::ptr<FileSource> getFileSource() const { return fileSource; }
+    inline util::ptr<Style> getStyle() const { return style; }
+    inline util::ptr<GlyphAtlas> getGlyphAtlas() { return glyphAtlas; }
+    inline util::ptr<GlyphStore> getGlyphStore() { return glyphStore; }
+    inline util::ptr<SpriteAtlas> getSpriteAtlas() { return spriteAtlas; }
+    util::ptr<Sprite> getSprite();
+    inline util::ptr<Texturepool> getTexturepool() { return texturepool; }
+    inline util::ptr<uv::loop> getLoop() { return loop; }
+    uv::worker &getWorker();
     inline timestamp getAnimationTime() const { return animationTime; }
     inline timestamp getTime() const { return animationTime; }
     void updateTiles();
@@ -141,7 +155,7 @@ private:
     void setup();
 
     void updateSources();
-    void updateSources(const std::shared_ptr<StyleLayerGroup> &group);
+    void updateSources(const util::ptr<StyleLayerGroup> &group);
 
     void updateRenderState();
 
@@ -154,15 +168,16 @@ private:
 
     // Unconditionally performs a render with the current map state.
     void render();
-    void renderLayers(std::shared_ptr<StyleLayerGroup> group);
+    void renderLayers(util::ptr<StyleLayerGroup> group);
 
 private:
     bool async = false;
-    std::shared_ptr<uv::loop> loop;
+    util::ptr<uv::loop> loop;
+    std::unique_ptr<uv::worker> workers;
     std::unique_ptr<uv::thread> thread;
-    uv_async_t *async_terminate = nullptr;
-    uv_async_t *async_render = nullptr;
-    uv_async_t *async_cleanup = nullptr;
+    std::unique_ptr<uv_async_t> async_terminate;
+    std::unique_ptr<uv_async_t> async_render;
+    std::unique_ptr<uv_async_t> async_cleanup;
 
 private:
     // If cleared, the next time the render thread attempts to render the map, it will *actually*
@@ -177,24 +192,33 @@ private:
     // ready for rendering.
     std::atomic_flag is_rendered = ATOMIC_FLAG_INIT;
 
+    // Stores whether the map thread has been stopped already.
+    std::atomic_bool is_stopped;
+
 public:
     View &view;
 
 private:
+#ifndef NDEBUG
+    const unsigned long main_thread;
+    unsigned long map_thread = -1;
+#endif
+
     Transform transform;
     TransformState state;
 
-    std::shared_ptr<FileSource> fileSource;
+    util::ptr<FileSource> fileSource;
 
-    std::shared_ptr<Style> style;
-    std::shared_ptr<GlyphAtlas> glyphAtlas;
-    std::shared_ptr<GlyphStore> glyphStore;
-    std::shared_ptr<SpriteAtlas> spriteAtlas;
-    std::shared_ptr<Sprite> sprite;
-    std::shared_ptr<Texturepool> texturepool;
+    util::ptr<Style> style;
+    util::ptr<GlyphAtlas> glyphAtlas;
+    util::ptr<GlyphStore> glyphStore;
+    util::ptr<SpriteAtlas> spriteAtlas;
+    util::ptr<Sprite> sprite;
+    util::ptr<Texturepool> texturepool;
 
     Painter painter;
 
+    std::string styleURL;
     std::string styleJSON = "";
     std::string accessToken = "";
 
@@ -203,7 +227,7 @@ private:
 
     int indent = 0;
 
-    std::set<std::shared_ptr<StyleSource>> activeSources;
+    std::set<util::ptr<StyleSource>> activeSources;
 
 };
 
diff --git a/include/mbgl/map/raster_tile_data.hpp b/include/mbgl/map/raster_tile_data.hpp
index 98aa3baaf5..14833c0d84 100644
--- a/include/mbgl/map/raster_tile_data.hpp
+++ b/include/mbgl/map/raster_tile_data.hpp
@@ -5,8 +5,6 @@
 #include <mbgl/map/tile_data.hpp>
 #include <mbgl/renderer/raster_bucket.hpp>
 
-#include <memory>
-
 namespace mbgl {
 
 class Map;
@@ -18,12 +16,12 @@ class RasterTileData : public TileData {
     friend class TileParser;
 
 public:
-    RasterTileData(Tile::ID id, Map &map, const SourceInfo &source);
+    RasterTileData(Tile::ID id, Map &map, const util::ptr<SourceInfo> &source);
     ~RasterTileData();
 
     virtual void parse();
-    virtual void render(Painter &painter, std::shared_ptr<StyleLayer> layer_desc, const mat4 &matrix);
-    virtual bool hasData(std::shared_ptr<StyleLayer> layer_desc) const;
+    virtual void render(Painter &painter, util::ptr<StyleLayer> layer_desc, const mat4 &matrix);
+    virtual bool hasData(util::ptr<StyleLayer> layer_desc) const;
 
 protected:
     StyleBucketRaster properties;
diff --git a/include/mbgl/map/source.hpp b/include/mbgl/map/source.hpp
index cb069db272..e74ddb9902 100644
--- a/include/mbgl/map/source.hpp
+++ b/include/mbgl/map/source.hpp
@@ -8,12 +8,12 @@
 #include <mbgl/util/noncopyable.hpp>
 #include <mbgl/util/time.hpp>
 #include <mbgl/util/mat4.hpp>
+#include <mbgl/util/ptr.hpp>
 
 #include <cstdint>
 #include <forward_list>
 #include <iosfwd>
 #include <map>
-#include <memory>
 
 namespace mbgl {
 
@@ -25,7 +25,7 @@ struct box;
 
 class Source : public std::enable_shared_from_this<Source>, private util::noncopyable {
 public:
-    Source(SourceInfo& info);
+    Source(const util::ptr<SourceInfo>& info);
 
     void load(Map &map);
 
@@ -33,8 +33,8 @@ public:
     void updateMatrices(const mat4 &projMatrix, const TransformState &transform);
     void drawClippingMasks(Painter &painter);
     size_t getTileCount() const;
-    void render(Painter &painter, std::shared_ptr<StyleLayer> layer_desc);
-    void render(Painter &painter, std::shared_ptr<StyleLayer> layer_desc, const Tile::ID &id, const mat4 &matrix);
+    void render(Painter &painter, util::ptr<StyleLayer> layer_desc);
+    void render(Painter &painter, util::ptr<StyleLayer> layer_desc, const Tile::ID &id, const mat4 &matrix);
     void finishRender(Painter &painter);
 
     std::forward_list<Tile::ID> getIDs() const;
@@ -54,7 +54,7 @@ private:
 
     double getZoom(const TransformState &state) const;
 
-    SourceInfo& info;
+    util::ptr<SourceInfo> info;
     bool loaded = false;
 
     // Stores the time when this source was most recently updated.
diff --git a/include/mbgl/map/sprite.hpp b/include/mbgl/map/sprite.hpp
index 6461a5e33d..454ebd8886 100644
--- a/include/mbgl/map/sprite.hpp
+++ b/include/mbgl/map/sprite.hpp
@@ -3,11 +3,11 @@
 
 #include <mbgl/util/image.hpp>
 #include <mbgl/util/noncopyable.hpp>
+#include <mbgl/util/ptr.hpp>
 
 #include <cstdint>
 #include <atomic>
 #include <iosfwd>
-#include <memory>
 #include <string>
 #include <unordered_map>
 #include <future>
@@ -34,11 +34,11 @@ public:
 class Sprite : public std::enable_shared_from_this<Sprite>, private util::noncopyable {
 private:
     struct Key {};
-    void load(const std::shared_ptr<FileSource> &fileSource);
+    void load(const util::ptr<FileSource> &fileSource);
 
 public:
     Sprite(const Key &, const std::string& base_url, float pixelRatio);
-    static std::shared_ptr<Sprite> Create(const std::string& base_url, float pixelRatio, const std::shared_ptr<FileSource> &fileSource);
+    static util::ptr<Sprite> Create(const std::string& base_url, float pixelRatio, const util::ptr<FileSource> &fileSource);
 
     const SpritePosition &getSpritePosition(const std::string& name) const;
 
diff --git a/include/mbgl/map/tile.hpp b/include/mbgl/map/tile.hpp
index 75ced7e384..b9f0556add 100644
--- a/include/mbgl/map/tile.hpp
+++ b/include/mbgl/map/tile.hpp
@@ -3,6 +3,7 @@
 
 #include <mbgl/util/mat4.hpp>
 #include <mbgl/util/noncopyable.hpp>
+#include <mbgl/util/ptr.hpp>
 
 #include <cstdint>
 #include <bitset>
@@ -10,7 +11,6 @@
 #include <cstdint>
 #include <forward_list>
 #include <iosfwd>
-#include <memory>
 #include <string>
 
 namespace mbgl {
@@ -78,7 +78,7 @@ public:
     const Tile::ID id;
     ClipID clip;
     mat4 matrix;
-    std::shared_ptr<TileData> data;
+    util::ptr<TileData> data;
 };
 
 }
diff --git a/include/mbgl/map/tile_data.hpp b/include/mbgl/map/tile_data.hpp
index 9aaef84e04..07cf19c5c8 100644
--- a/include/mbgl/map/tile_data.hpp
+++ b/include/mbgl/map/tile_data.hpp
@@ -6,11 +6,11 @@
 #include <mbgl/geometry/debug_font_buffer.hpp>
 
 #include <mbgl/util/noncopyable.hpp>
+#include <mbgl/util/ptr.hpp>
 
 #include <atomic>
 #include <exception>
 #include <iosfwd>
-#include <memory>
 #include <string>
 
 namespace mbgl {
@@ -19,8 +19,7 @@ class Map;
 class Painter;
 class SourceInfo;
 class StyleLayer;
-
-namespace platform { class Request; }
+class Request;
 
 class TileData : public std::enable_shared_from_this<TileData>,
              private util::noncopyable {
@@ -29,7 +28,7 @@ public:
     struct geometry_too_long_exception : exception {};
 
 public:
-    typedef std::shared_ptr<TileData> Ptr;
+    typedef util::ptr<TileData> Ptr;
 
     enum class State {
         invalid,
@@ -41,7 +40,7 @@ public:
     };
 
 public:
-    TileData(Tile::ID id, Map &map, const SourceInfo &source);
+    TileData(Tile::ID id, Map &map, const util::ptr<SourceInfo> &source);
     ~TileData();
 
     void request();
@@ -57,8 +56,8 @@ public:
     virtual void beforeParse();
     virtual void parse() = 0;
     virtual void afterParse();
-    virtual void render(Painter &painter, std::shared_ptr<StyleLayer> layer_desc, const mat4 &matrix) = 0;
-    virtual bool hasData(std::shared_ptr<StyleLayer> layer_desc) const = 0;
+    virtual void render(Painter &painter, util::ptr<StyleLayer> layer_desc, const mat4 &matrix) = 0;
+    virtual bool hasData(util::ptr<StyleLayer> layer_desc) const = 0;
 
 
 public:
@@ -69,10 +68,10 @@ protected:
     Map &map;
 
 public:
-    const SourceInfo &source;
+    util::ptr<SourceInfo> source;
 
 protected:
-    std::weak_ptr<platform::Request> req;
+    std::unique_ptr<Request> req;
     std::string data;
 
     // Contains the tile ID string for painting debug information.
diff --git a/include/mbgl/map/tile_parser.hpp b/include/mbgl/map/tile_parser.hpp
index fa64dad6d5..ddb4b98820 100644
--- a/include/mbgl/map/tile_parser.hpp
+++ b/include/mbgl/map/tile_parser.hpp
@@ -4,10 +4,10 @@
 #include <mbgl/map/vector_tile.hpp>
 #include <mbgl/style/filter_expression.hpp>
 #include <mbgl/text/glyph.hpp>
+#include <mbgl/util/ptr.hpp>
 
 #include <cstdint>
 #include <iosfwd>
-#include <memory>
 #include <string>
 
 namespace mbgl {
@@ -32,11 +32,11 @@ class Collision;
 class TileParser {
 public:
     TileParser(const std::string &data, VectorTileData &tile,
-               const std::shared_ptr<const Style> &style,
-               const std::shared_ptr<GlyphAtlas> &glyphAtlas,
-               const std::shared_ptr<GlyphStore> &glyphStore,
-               const std::shared_ptr<SpriteAtlas> &spriteAtlas,
-               const std::shared_ptr<Sprite> &sprite);
+               const util::ptr<const Style> &style,
+               const util::ptr<GlyphAtlas> &glyphAtlas,
+               const util::ptr<GlyphStore> &glyphStore,
+               const util::ptr<SpriteAtlas> &spriteAtlas,
+               const util::ptr<Sprite> &sprite);
     ~TileParser();
 
 public:
@@ -44,11 +44,11 @@ public:
 
 private:
     bool obsolete() const;
-    void parseStyleLayers(std::shared_ptr<StyleLayerGroup> group);
-    std::unique_ptr<Bucket> createBucket(std::shared_ptr<StyleBucket> bucket_desc);
+    void parseStyleLayers(util::ptr<StyleLayerGroup> group);
+    std::unique_ptr<Bucket> createBucket(util::ptr<StyleBucket> bucket_desc);
 
     std::unique_ptr<Bucket> createFillBucket(const VectorTileLayer& layer, const FilterExpression &filter, const StyleBucketFill &fill);
-    std::unique_ptr<Bucket> createRasterBucket(const std::shared_ptr<Texturepool> &texturepool, const StyleBucketRaster &raster);
+    std::unique_ptr<Bucket> createRasterBucket(const util::ptr<Texturepool> &texturepool, const StyleBucketRaster &raster);
     std::unique_ptr<Bucket> createLineBucket(const VectorTileLayer& layer, const FilterExpression &filter, const StyleBucketLine &line);
     std::unique_ptr<Bucket> createSymbolBucket(const VectorTileLayer& layer, const FilterExpression &filter, const StyleBucketSymbol &symbol);
 
@@ -59,12 +59,12 @@ private:
     VectorTileData& tile;
 
     // Cross-thread shared data.
-    std::shared_ptr<const Style> style;
-    std::shared_ptr<GlyphAtlas> glyphAtlas;
-    std::shared_ptr<GlyphStore> glyphStore;
-    std::shared_ptr<SpriteAtlas> spriteAtlas;
-    std::shared_ptr<Sprite> sprite;
-    std::shared_ptr<Texturepool> texturePool;
+    util::ptr<const Style> style;
+    util::ptr<GlyphAtlas> glyphAtlas;
+    util::ptr<GlyphStore> glyphStore;
+    util::ptr<SpriteAtlas> spriteAtlas;
+    util::ptr<Sprite> sprite;
+    util::ptr<Texturepool> texturePool;
 
     std::unique_ptr<Collision> collision;
 };
diff --git a/include/mbgl/map/transform.hpp b/include/mbgl/map/transform.hpp
index d0f56b7fba..5404f333c1 100644
--- a/include/mbgl/map/transform.hpp
+++ b/include/mbgl/map/transform.hpp
@@ -98,10 +98,10 @@ private:
     // cache values for spherical mercator math
     double Bc, Cc;
 
-    std::forward_list<std::shared_ptr<util::transition>> transitions;
-    std::shared_ptr<util::transition> scale_timeout;
-    std::shared_ptr<util::transition> rotate_timeout;
-    std::shared_ptr<util::transition> pan_timeout;
+    std::forward_list<util::ptr<util::transition>> transitions;
+    util::ptr<util::transition> scale_timeout;
+    util::ptr<util::transition> rotate_timeout;
+    util::ptr<util::transition> pan_timeout;
 };
 
 }
diff --git a/include/mbgl/map/vector_tile_data.hpp b/include/mbgl/map/vector_tile_data.hpp
index deb628e485..9de666c84f 100644
--- a/include/mbgl/map/vector_tile_data.hpp
+++ b/include/mbgl/map/vector_tile_data.hpp
@@ -26,14 +26,14 @@ class VectorTileData : public TileData {
     friend class TileParser;
 
 public:
-    VectorTileData(Tile::ID id, Map &map, const SourceInfo &source);
+    VectorTileData(Tile::ID id, Map &map, const util::ptr<SourceInfo> &source);
     ~VectorTileData();
 
     virtual void beforeParse();
     virtual void parse();
     virtual void afterParse();
-    virtual void render(Painter &painter, std::shared_ptr<StyleLayer> layer_desc, const mat4 &matrix);
-    virtual bool hasData(std::shared_ptr<StyleLayer> layer_desc) const;
+    virtual void render(Painter &painter, util::ptr<StyleLayer> layer_desc, const mat4 &matrix);
+    virtual bool hasData(util::ptr<StyleLayer> layer_desc) const;
 
 protected:
     // Holds the actual geometries in this tile.
diff --git a/include/mbgl/map/view.hpp b/include/mbgl/map/view.hpp
index 3e2f1a4b5a..395a05d435 100644
--- a/include/mbgl/map/view.hpp
+++ b/include/mbgl/map/view.hpp
@@ -45,6 +45,8 @@ public:
         return 0;
     }
 
+    virtual void notify() = 0;
+
     // Notifies a watcher of map x/y/scale/rotation changes.
     // Must only be called from the same thread that caused the change.
     // Must not be called from the render thread.
diff --git a/include/mbgl/platform/event.hpp b/include/mbgl/platform/event.hpp
index 1676f40d2c..d2a06618a3 100644
--- a/include/mbgl/platform/event.hpp
+++ b/include/mbgl/platform/event.hpp
@@ -29,6 +29,7 @@ enum class Event : uint8_t {
     ParseStyle,
     ParseTile,
     Render,
+    Database,
     HttpRequest,
     Sprite,
 };
@@ -40,6 +41,7 @@ MBGL_DEFINE_ENUM_CLASS(EventClass, Event, {
     { Event::ParseStyle, "ParseStyle" },
     { Event::ParseTile, "ParseTile" },
     { Event::Render, "Render" },
+    { Event::Database, "Database" },
     { Event::HttpRequest, "HttpRequest" },
     { Event::Sprite, "Sprite" },
     { Event(-1), "Unknown" },
diff --git a/include/mbgl/platform/platform.hpp b/include/mbgl/platform/platform.hpp
index 22405a4cfd..b7107bb9cd 100644
--- a/include/mbgl/platform/platform.hpp
+++ b/include/mbgl/platform/platform.hpp
@@ -4,7 +4,6 @@
 #include <mbgl/util/uv.hpp>
 
 #include <memory>
-#include <functional>
 #include <string>
 
 namespace mbgl {
@@ -12,30 +11,14 @@ namespace platform {
 
 class Request;
 
-struct Response {
-    Response(std::function<void(Response *)> callback) : callback(callback) {}
-    int16_t code = -1;
-    std::string body;
-    std::string error_message;
-    std::function<void(Response *)> callback;
-};
-
-// Makes an HTTP request of a URL, preferrably on a background thread, and calls a function with the
-// results in the original thread (which runs the libuv loop).
-// If the loop pointer is NULL, the callback function will be called on an arbitrary thread.
-// Returns a cancellable request.
-std::shared_ptr<Request> request_http(const std::string &url,
-                                      std::function<void(Response *)> callback,
-                                      std::shared_ptr<uv::loop> loop = nullptr);
-
 // Uppercase a string, potentially using platform-specific routines.
 std::string uppercase(const std::string &string);
 
 // Lowercase a string, potentially using platform-specific routines.
 std::string lowercase(const std::string &string);
 
-// Cancels an HTTP request.
-void cancel_request_http(const std::shared_ptr<Request> &req);
+// Returns the path to the default cache database on this system.
+std::string defaultCacheDatabase();
 
 // Shows an alpha image with the specified dimensions in a named window.
 void show_debug_image(std::string name, const char *data, size_t width, size_t height);
diff --git a/include/mbgl/platform/request.hpp b/include/mbgl/platform/request.hpp
deleted file mode 100644
index 2a231769c1..0000000000
--- a/include/mbgl/platform/request.hpp
+++ /dev/null
@@ -1,41 +0,0 @@
-#ifndef MBGL_PLATFORM_REQUEST
-#define MBGL_PLATFORM_REQUEST
-
-#include <string>
-#include <functional>
-#include <memory>
-#include <atomic>
-
-#include <mbgl/util/noncopyable.hpp>
-#include <mbgl/util/uv.hpp>
-
-namespace mbgl {
-namespace platform {
-
-struct Response;
-
-class Request : public std::enable_shared_from_this<Request>, private util::noncopyable {
-public:
-    Request(const std::string &url,
-            std::function<void(Response *)> callback,
-            std::shared_ptr<uv::loop> loop);
-    ~Request();
-
-    void complete();
-
-private:
-    static void complete(uv_async_t *async, int status);
-
-public:
-    const std::string url;
-    std::unique_ptr<Response> res;
-    std::atomic<bool> cancelled;
-
-public:
-    uv_async_t *async = nullptr;
-    std::shared_ptr<uv::loop> loop;
-};
-}
-}
-
-#endif
diff --git a/include/mbgl/renderer/bucket.hpp b/include/mbgl/renderer/bucket.hpp
index 1391f6e3e3..696bfb1110 100644
--- a/include/mbgl/renderer/bucket.hpp
+++ b/include/mbgl/renderer/bucket.hpp
@@ -1,11 +1,11 @@
 #ifndef MBGL_RENDERER_BUCKET
 #define MBGL_RENDERER_BUCKET
 
-#include <string>
-#include <memory>
 #include <mbgl/map/tile.hpp>
 #include <mbgl/util/noncopyable.hpp>
 
+#include <string>
+
 namespace mbgl {
 
 class Painter;
@@ -13,7 +13,7 @@ class StyleLayer;
 
 class Bucket : private util::noncopyable {
 public:
-    virtual void render(Painter& painter, std::shared_ptr<StyleLayer> layer_desc, const Tile::ID& id, const mat4 &matrix) = 0;
+    virtual void render(Painter& painter, util::ptr<StyleLayer> layer_desc, const Tile::ID& id, const mat4 &matrix) = 0;
     virtual bool hasData() const = 0;
     virtual ~Bucket() {}
 
diff --git a/include/mbgl/renderer/debug_bucket.hpp b/include/mbgl/renderer/debug_bucket.hpp
index 660b7fcba8..fb6cfb4cae 100644
--- a/include/mbgl/renderer/debug_bucket.hpp
+++ b/include/mbgl/renderer/debug_bucket.hpp
@@ -6,7 +6,6 @@
 #include <mbgl/geometry/vao.hpp>
 
 #include <vector>
-#include <memory>
 
 #ifndef BUFFER_OFFSET
 #define BUFFER_OFFSET(i) ((char *)nullptr + (i))
@@ -20,7 +19,7 @@ class DebugBucket : public Bucket {
 public:
     DebugBucket(DebugFontBuffer& fontBuffer);
 
-    virtual void render(Painter& painter, std::shared_ptr<StyleLayer> layer_desc, const Tile::ID& id, const mat4 &matrix);
+    virtual void render(Painter& painter, util::ptr<StyleLayer> layer_desc, const Tile::ID& id, const mat4 &matrix);
     virtual bool hasData() const;
 
     void drawLines(PlainShader& shader);
diff --git a/include/mbgl/renderer/fill_bucket.hpp b/include/mbgl/renderer/fill_bucket.hpp
index 15868e4092..ae766ec28d 100644
--- a/include/mbgl/renderer/fill_bucket.hpp
+++ b/include/mbgl/renderer/fill_bucket.hpp
@@ -44,7 +44,7 @@ public:
                const StyleBucketFill& properties);
     ~FillBucket();
 
-    virtual void render(Painter& painter, std::shared_ptr<StyleLayer> layer_desc, const Tile::ID& id, const mat4 &matrix);
+    virtual void render(Painter& painter, util::ptr<StyleLayer> layer_desc, const Tile::ID& id, const mat4 &matrix);
     virtual bool hasData() const;
 
     void addGeometry(pbf& data);
diff --git a/include/mbgl/renderer/line_bucket.hpp b/include/mbgl/renderer/line_bucket.hpp
index 8babb734ed..7337ca80ad 100644
--- a/include/mbgl/renderer/line_bucket.hpp
+++ b/include/mbgl/renderer/line_bucket.hpp
@@ -1,13 +1,12 @@
 #ifndef MBGL_RENDERER_LINEBUCKET
 #define MBGL_RENDERER_LINEBUCKET
 
-#include "bucket.hpp"
+#include <mbgl/renderer/bucket.hpp>
 #include <mbgl/geometry/vao.hpp>
 #include <mbgl/geometry/elements_buffer.hpp>
 #include <mbgl/geometry/line_buffer.hpp>
 #include <mbgl/style/style_bucket.hpp>
 
-#include <memory>
 #include <vector>
 
 namespace mbgl {
@@ -30,7 +29,7 @@ public:
                PointElementsBuffer& pointElementsBuffer,
                const StyleBucketLine& properties);
 
-    virtual void render(Painter& painter, std::shared_ptr<StyleLayer> layer_desc, const Tile::ID& id, const mat4 &matrix);
+    virtual void render(Painter& painter, util::ptr<StyleLayer> layer_desc, const Tile::ID& id, const mat4 &matrix);
     virtual bool hasData() const;
 
     void addGeometry(pbf& data);
diff --git a/include/mbgl/renderer/painter.hpp b/include/mbgl/renderer/painter.hpp
index 15331b9b67..0f9bd79173 100644
--- a/include/mbgl/renderer/painter.hpp
+++ b/include/mbgl/renderer/painter.hpp
@@ -22,6 +22,7 @@
 #include <mbgl/shader/gaussian_shader.hpp>
 
 #include <mbgl/map/transform_state.hpp>
+#include <mbgl/util/ptr.hpp>
 
 #include <map>
 #include <unordered_map>
@@ -73,7 +74,7 @@ public:
     void changeMatrix();
 
     // Renders a particular layer from a tile.
-    void renderTileLayer(const Tile& tile, std::shared_ptr<StyleLayer> layer_desc, const mat4 &matrix);
+    void renderTileLayer(const Tile& tile, util::ptr<StyleLayer> layer_desc, const mat4 &matrix);
 
     // Renders debug information for a tile.
     void renderTileDebug(const Tile& tile);
@@ -83,11 +84,11 @@ public:
 
     void renderDebugText(DebugBucket& bucket, const mat4 &matrix);
     void renderDebugText(const std::vector<std::string> &strings);
-    void renderFill(FillBucket& bucket, std::shared_ptr<StyleLayer> layer_desc, const Tile::ID& id, const mat4 &matrix);
-    void renderLine(LineBucket& bucket, std::shared_ptr<StyleLayer> layer_desc, const Tile::ID& id, const mat4 &matrix);
-    void renderSymbol(SymbolBucket& bucket, std::shared_ptr<StyleLayer> layer_desc, const Tile::ID& id, const mat4 &matrix);
-    void renderRaster(RasterBucket& bucket, std::shared_ptr<StyleLayer> layer_desc, const Tile::ID& id, const mat4 &matrix);
-    void renderBackground(std::shared_ptr<StyleLayer> layer_desc);
+    void renderFill(FillBucket& bucket, util::ptr<StyleLayer> layer_desc, const Tile::ID& id, const mat4 &matrix);
+    void renderLine(LineBucket& bucket, util::ptr<StyleLayer> layer_desc, const Tile::ID& id, const mat4 &matrix);
+    void renderSymbol(SymbolBucket& bucket, util::ptr<StyleLayer> layer_desc, const Tile::ID& id, const mat4 &matrix);
+    void renderRaster(RasterBucket& bucket, util::ptr<StyleLayer> layer_desc, const Tile::ID& id, const mat4 &matrix);
+    void renderBackground(util::ptr<StyleLayer> layer_desc);
 
     float saturationFactor(float saturation);
     float contrastFactor(float contrast);
@@ -97,7 +98,7 @@ public:
 
     void renderPrerenderedTexture(RasterBucket &bucket, const mat4 &matrix, const RasterProperties& properties);
 
-    void createPrerendered(RasterBucket& bucket, std::shared_ptr<StyleLayer> layer_desc, const Tile::ID& id);
+    void createPrerendered(RasterBucket& bucket, util::ptr<StyleLayer> layer_desc, const Tile::ID& id);
 
     void resize();
 
@@ -111,7 +112,7 @@ public:
     // Configures the painter strata that is used for early z-culling of fragments.
     void setStrata(float strata);
 
-    void drawClippingMasks(const std::set<std::shared_ptr<StyleSource>> &sources);
+    void drawClippingMasks(const std::set<util::ptr<StyleSource>> &sources);
     void drawClippingMask(const mat4& matrix, const ClipID& clip);
 
     void resetFramebuffer();
diff --git a/include/mbgl/renderer/raster_bucket.hpp b/include/mbgl/renderer/raster_bucket.hpp
index 66cceac8e7..794da3b143 100644
--- a/include/mbgl/renderer/raster_bucket.hpp
+++ b/include/mbgl/renderer/raster_bucket.hpp
@@ -16,9 +16,9 @@ class VertexArrayObject;
 
 class RasterBucket : public Bucket {
 public:
-    RasterBucket(const std::shared_ptr<Texturepool> &texturepool, const StyleBucketRaster& properties);
+    RasterBucket(const util::ptr<Texturepool> &texturepool, const StyleBucketRaster& properties);
 
-    virtual void render(Painter& painter, std::shared_ptr<StyleLayer> layer_desc, const Tile::ID& id, const mat4 &matrix);
+    virtual void render(Painter& painter, util::ptr<StyleLayer> layer_desc, const Tile::ID& id, const mat4 &matrix);
     virtual bool hasData() const;
 
     bool setImage(const std::string &data);
diff --git a/include/mbgl/renderer/symbol_bucket.hpp b/include/mbgl/renderer/symbol_bucket.hpp
index c71d276456..42682401ef 100644
--- a/include/mbgl/renderer/symbol_bucket.hpp
+++ b/include/mbgl/renderer/symbol_bucket.hpp
@@ -56,7 +56,7 @@ class SymbolBucket : public Bucket {
 public:
     SymbolBucket(const StyleBucketSymbol &properties, Collision &collision);
 
-    virtual void render(Painter &painter, std::shared_ptr<StyleLayer> layer_desc, const Tile::ID &id, const mat4 &matrix);
+    virtual void render(Painter &painter, util::ptr<StyleLayer> layer_desc, const Tile::ID &id, const mat4 &matrix);
     virtual bool hasData() const;
     virtual bool hasTextData() const;
     virtual bool hasIconData() const;
diff --git a/include/mbgl/storage/base_request.hpp b/include/mbgl/storage/base_request.hpp
new file mode 100644
index 0000000000..16ff24faa3
--- /dev/null
+++ b/include/mbgl/storage/base_request.hpp
@@ -0,0 +1,62 @@
+#ifndef MBGL_STORAGE_BASE_REQUEST
+#define MBGL_STORAGE_BASE_REQUEST
+
+#include <mbgl/storage/request_callback.hpp>
+#include <mbgl/util/ptr.hpp>
+
+#include <string>
+#include <forward_list>
+#include <functional>
+
+
+typedef struct uv_loop_s uv_loop_t;
+typedef struct uv_async_s uv_async_t;
+
+namespace mbgl {
+
+class Response;
+class Request;
+
+class BaseRequest {
+private:
+    // Make noncopyable and immovable
+    BaseRequest(const BaseRequest &) = delete;
+    BaseRequest(BaseRequest &&) = delete;
+    BaseRequest& operator=(const BaseRequest &) = delete;
+    BaseRequest& operator=(BaseRequest &&) = delete;
+
+public:
+    BaseRequest(const std::string &path);
+    virtual ~BaseRequest();
+
+    Callback *add(Callback &&callback, const util::ptr<BaseRequest> &request);
+    void remove(Callback *callback);
+
+    // Must be called by subclasses when a valid Response object is available. It will notify
+    // all listeners.
+    void notify();
+
+    // This function is called when the request ought to be stopped. Any subclass must make sure this
+    // is also called in its destructor. Calling this function repeatedly must be safe.
+    // This function must call notify().
+    virtual void cancel() = 0;
+
+    // This function is called when the request should be reattempted immediately. This is typically
+    // reaction to a network status change.
+    virtual void retryImmediately();
+
+public:
+    const unsigned long thread_id;
+    const std::string path;
+    std::unique_ptr<Response> response;
+
+protected:
+    // This object may hold a shared_ptr to itself. It does this to prevent destruction of this object
+    // while a request is in progress.
+    util::ptr<BaseRequest> self;
+    std::forward_list<std::unique_ptr<Callback>> callbacks;
+};
+
+}
+
+#endif
diff --git a/include/mbgl/storage/file_request.hpp b/include/mbgl/storage/file_request.hpp
new file mode 100644
index 0000000000..2f883728ff
--- /dev/null
+++ b/include/mbgl/storage/file_request.hpp
@@ -0,0 +1,27 @@
+#ifndef MBGL_STORAGE_FILE_REQUEST
+#define MBGL_STORAGE_FILE_REQUEST
+
+#include <mbgl/storage/base_request.hpp>
+
+namespace mbgl {
+
+typedef struct uv_loop_s uv_loop_t;
+
+struct FileRequestBaton;
+
+class FileRequest : public BaseRequest {
+public:
+    FileRequest(const std::string &path, uv_loop_t *loop);
+    ~FileRequest();
+
+    void cancel();
+
+private:
+    FileRequestBaton *ptr = nullptr;
+
+    friend struct FileRequestBaton;
+};
+
+}
+
+#endif
\ No newline at end of file
diff --git a/include/mbgl/storage/file_request_baton.hpp b/include/mbgl/storage/file_request_baton.hpp
new file mode 100644
index 0000000000..0f1968ca13
--- /dev/null
+++ b/include/mbgl/storage/file_request_baton.hpp
@@ -0,0 +1,35 @@
+#ifndef MBGL_STORAGE_FILE_REQUEST_BATON
+#define MBGL_STORAGE_FILE_REQUEST_BATON
+
+#include <mbgl/storage/file_request.hpp>
+
+#include <uv.h>
+
+namespace mbgl {
+
+struct FileRequestBaton {
+    FileRequestBaton(FileRequest *request_, const std::string &path, uv_loop_t *loop);
+    ~FileRequestBaton();
+
+    void cancel();
+    static void file_opened(uv_fs_t *req);
+    static void file_stated(uv_fs_t *req);
+    static void file_read(uv_fs_t *req);
+    static void file_closed(uv_fs_t *req);
+    static void notify_error(uv_fs_t *req);
+    static void cleanup(uv_fs_t *req);
+
+    const unsigned long thread_id;
+    FileRequest *request = nullptr;
+    uv_fs_t req;
+    uv_file fd = -1;
+    bool canceled = false;
+    std::string body;
+    uv_buf_t buffer;
+};
+
+
+}
+
+
+#endif
diff --git a/include/mbgl/storage/file_source.hpp b/include/mbgl/storage/file_source.hpp
new file mode 100644
index 0000000000..4b17cd29a7
--- /dev/null
+++ b/include/mbgl/storage/file_source.hpp
@@ -0,0 +1,55 @@
+#ifndef MBGL_STORAGE_FILE_SOURCE
+#define MBGL_STORAGE_FILE_SOURCE
+
+#include <mbgl/storage/resource_type.hpp>
+#include <mbgl/storage/request.hpp>
+
+#include <string>
+#include <unordered_map>
+#include <functional>
+
+typedef struct uv_loop_s uv_loop_t;
+typedef struct uv_messenger_s uv_messenger_t;
+
+namespace mbgl {
+
+class BaseRequest;
+class SQLiteStore;
+
+class FileSource {
+private:
+    FileSource(const FileSource &) = delete;
+    FileSource(FileSource &&) = delete;
+    FileSource& operator=(const FileSource &) = delete;
+    FileSource& operator=(FileSource &&) = delete;
+
+public:
+    FileSource(uv_loop_t *loop, const std::string &path);
+    ~FileSource();
+
+public:
+    // Stores and retrieves the base path/URL for relative requests
+    void setBase(const std::string &value);
+    const std::string &getBase() const;
+
+    std::unique_ptr<Request> request(ResourceType type, const std::string &url);
+
+    void prepare(std::function<void()> fn);
+
+    void retryAllPending();
+
+private:
+    const unsigned long thread_id;
+
+    // Stores a URL that is used as a base for loading resources with relative path.
+    std::string base;
+
+    std::unordered_map<std::string, std::weak_ptr<BaseRequest>> pending;
+    util::ptr<SQLiteStore> store;
+    uv_loop_t *loop = nullptr;
+    uv_messenger_t *queue = nullptr;
+};
+
+}
+
+#endif
diff --git a/include/mbgl/storage/http_request.hpp b/include/mbgl/storage/http_request.hpp
new file mode 100644
index 0000000000..ec76f1147c
--- /dev/null
+++ b/include/mbgl/storage/http_request.hpp
@@ -0,0 +1,57 @@
+#ifndef MBGL_STORAGE_HTTP_REQUEST
+#define MBGL_STORAGE_HTTP_REQUEST
+
+#include <mbgl/storage/resource_type.hpp>
+#include <mbgl/storage/base_request.hpp>
+#include <mbgl/storage/http_request_baton.hpp>
+
+#include <string>
+#include <memory>
+#include <cassert>
+
+typedef struct uv_loop_s uv_loop_t;
+typedef struct uv_timer_s uv_timer_t;
+
+namespace mbgl {
+
+struct CacheRequestBaton;
+struct HTTPRequestBaton;
+struct CacheEntry;
+class SQLiteStore;
+
+class HTTPRequest : public BaseRequest {
+public:
+    HTTPRequest(ResourceType type, const std::string &path, uv_loop_t *loop, util::ptr<SQLiteStore> store);
+    ~HTTPRequest();
+
+    void cancel();
+    void retryImmediately();
+
+private:
+    void startCacheRequest();
+    void handleCacheResponse(std::unique_ptr<Response> &&response);
+    void startHTTPRequest(std::unique_ptr<Response> &&res);
+    void handleHTTPResponse(HTTPResponseType responseType, std::unique_ptr<Response> &&response);
+
+    void retryHTTPRequest(std::unique_ptr<Response> &&res, uint64_t timeout);
+
+    void removeCacheBaton();
+    void removeHTTPBaton();
+    void removeBackoffTimer();
+
+private:
+    const unsigned long thread_id;
+    uv_loop_t *const loop;
+    CacheRequestBaton *cache_baton = nullptr;
+    util::ptr<HTTPRequestBaton> http_baton;
+    uv_timer_t *backoff_timer = nullptr;
+    util::ptr<SQLiteStore> store;
+    const ResourceType type;
+    uint8_t attempts = 0;
+
+    friend struct HTTPRequestBaton;
+};
+
+}
+
+#endif
\ No newline at end of file
diff --git a/include/mbgl/storage/http_request_baton.hpp b/include/mbgl/storage/http_request_baton.hpp
new file mode 100644
index 0000000000..279784ec25
--- /dev/null
+++ b/include/mbgl/storage/http_request_baton.hpp
@@ -0,0 +1,73 @@
+#ifndef MBGL_STORAGE_HTTP_REQUEST_BATON
+#define MBGL_STORAGE_HTTP_REQUEST_BATON
+
+#include <mbgl/storage/response.hpp>
+#include <mbgl/util/ptr.hpp>
+
+#include <string>
+
+typedef struct uv_async_s uv_async_t;
+
+namespace mbgl {
+
+class HTTPRequest;
+
+enum class HTTPResponseType : int8_t {
+    // This error probably won't be resolved by retrying anytime soon. We are giving up.
+    PermanentError = -5,
+
+    // This error might be resolved by waiting some time (e.g. server issues).
+    // We are going to do an exponential back-off and will try again in a few seconds.
+    TemporaryError = -4,
+
+    // This error was caused by a temporary error and it is likely that it will be resolved
+    // immediately. We are going to try again right away. This is like the TemporaryError, except
+    // that we will not perform exponential back-off.
+    SingularError = -3,
+
+    // This error might be resolved once the network reachability status changes.
+    // We are going to watch the network status for changes and will retry as soon as the operating
+    // system notifies us of a network status change.
+    ConnectionError = -2,
+
+    // The request was canceled programatically.
+    Canceled = -1,
+
+    // The request is still in progress.
+    Unknown = 0,
+
+    // The request returned data successfully. We retrieved and decoded the data successfully.
+    Successful = 1,
+
+    // The request confirmed that the data wasn't changed. We already have the data.
+    NotModified = 2,
+};
+
+struct HTTPRequestBaton {
+    HTTPRequestBaton(const std::string &path);
+    ~HTTPRequestBaton();
+
+    const unsigned long thread_id;
+    const std::string path;
+
+    HTTPRequest *request = nullptr;
+    uv_async_t *async = nullptr;
+
+    HTTPResponseType type = HTTPResponseType::Unknown;
+    std::unique_ptr<Response> response;
+
+    // Implementation specific use.
+    void *ptr = nullptr;
+
+    // IMPLEMENT THESE 3 PLATFORM SPECIFIC FUNCTIONS:
+
+    // Begin the HTTP request. Platform-specific implementation.
+    static void start(const util::ptr<HTTPRequestBaton> &ptr);
+
+    // This will be called to stop/cancel the HTTP request (if possible). Platform-specific implementation.
+    static void stop(const util::ptr<HTTPRequestBaton> &ptr);
+};
+
+}
+
+#endif
diff --git a/include/mbgl/storage/request.hpp b/include/mbgl/storage/request.hpp
new file mode 100644
index 0000000000..e603ee527a
--- /dev/null
+++ b/include/mbgl/storage/request.hpp
@@ -0,0 +1,39 @@
+#ifndef MBGL_STORAGE_REQUEST
+#define MBGL_STORAGE_REQUEST
+
+#include <mbgl/storage/request_callback.hpp>
+#include <mbgl/storage/response.hpp>
+#include <mbgl/util/ptr.hpp>
+
+#include <forward_list>
+
+typedef struct uv_loop_s uv_loop_t;
+
+namespace mbgl {
+
+class BaseRequest;
+
+class Request {
+private:
+    Request(const Request &) = delete;
+    Request(Request &&) = delete;
+    Request& operator=(const Request &) = delete;
+    Request& operator=(Request &&) = delete;
+
+public:
+    Request(const util::ptr<BaseRequest> &base);
+    ~Request();
+
+    void onload(CompletedCallback cb);
+    void oncancel(AbortedCallback cb);
+    void cancel();
+
+private:
+    const unsigned long thread_id;
+    util::ptr<BaseRequest> base;
+    std::forward_list<Callback *> callbacks;
+};
+
+}
+
+#endif
\ No newline at end of file
diff --git a/include/mbgl/storage/request_callback.hpp b/include/mbgl/storage/request_callback.hpp
new file mode 100644
index 0000000000..01427bd96d
--- /dev/null
+++ b/include/mbgl/storage/request_callback.hpp
@@ -0,0 +1,22 @@
+#ifndef MBGL_STORAGE_REQUEST_CALLBACK
+#define MBGL_STORAGE_REQUEST_CALLBACK
+
+#include <mbgl/util/variant.hpp>
+
+#include <functional>
+
+namespace mbgl {
+
+class Response;
+
+using CompletedCallback = std::function<void(const Response &)>;
+using AbortedCallback = std::function<void()>;
+
+using Callback = mapbox::util::variant<
+    CompletedCallback,
+    AbortedCallback
+>;
+
+}
+
+#endif
diff --git a/include/mbgl/storage/resource_type.hpp b/include/mbgl/storage/resource_type.hpp
new file mode 100644
index 0000000000..b7204a9fa1
--- /dev/null
+++ b/include/mbgl/storage/resource_type.hpp
@@ -0,0 +1,18 @@
+#ifndef MBGL_STORAGE_RESOURCE_TYPE
+#define MBGL_STORAGE_RESOURCE_TYPE
+
+#include <cstdint>
+
+namespace mbgl {
+
+enum class ResourceType : uint8_t {
+    Unknown = 0,
+    Tile = 1,
+    Glyphs = 2,
+    Image = 3,
+    JSON = 4
+};
+
+}
+
+#endif
diff --git a/include/mbgl/storage/response.hpp b/include/mbgl/storage/response.hpp
new file mode 100644
index 0000000000..9357ad3c63
--- /dev/null
+++ b/include/mbgl/storage/response.hpp
@@ -0,0 +1,26 @@
+#ifndef MBGL_STORAGE_RESPONSE
+#define MBGL_STORAGE_RESPONSE
+
+#include <string>
+#include <ctime>
+
+namespace mbgl {
+
+
+
+class Response {
+public:
+    long code = 0;
+    int64_t modified = 0;
+    int64_t expires = 0;
+    std::string etag;
+    std::string data;
+
+    std::string message;
+
+    static int64_t parseCacheControl(const char *value);
+};
+
+}
+
+#endif
\ No newline at end of file
diff --git a/include/mbgl/storage/sqlite_store.hpp b/include/mbgl/storage/sqlite_store.hpp
new file mode 100644
index 0000000000..cb7730d0bf
--- /dev/null
+++ b/include/mbgl/storage/sqlite_store.hpp
@@ -0,0 +1,47 @@
+#ifndef MBGL_STORAGE_SQLITE_STORE
+#define MBGL_STORAGE_SQLITE_STORE
+
+#include <mbgl/storage/file_source.hpp>
+#include <mbgl/storage/response.hpp>
+
+#include <uv.h>
+
+#include <string>
+
+typedef struct uv_worker_s uv_worker_t;
+
+namespace mapbox {
+namespace sqlite {
+class Database;
+}
+}
+
+namespace mbgl {
+
+class SQLiteStore {
+public:
+    SQLiteStore(uv_loop_t *loop, const std::string &path);
+    ~SQLiteStore();
+
+    typedef void (*GetCallback)(std::unique_ptr<Response> &&entry, void *ptr);
+
+    void get(const std::string &path, GetCallback cb, void *ptr);
+    void put(const std::string &path, ResourceType type, const Response &entry);
+    void updateExpiration(const std::string &path, int64_t expires);
+
+private:
+    void createSchema();
+    void closeDatabase();
+    static void runGet(uv_work_t *req);
+    static void runPut(uv_work_t *req);
+    static void deliverResult(uv_work_t *req, int status);
+
+private:
+    const unsigned long thread_id;
+    util::ptr<mapbox::sqlite::Database> db;
+    uv_worker_t *worker = nullptr;
+};
+
+}
+
+#endif
diff --git a/include/mbgl/style/style.hpp b/include/mbgl/style/style.hpp
index c09de6ebba..56f318ecbb 100644
--- a/include/mbgl/style/style.hpp
+++ b/include/mbgl/style/style.hpp
@@ -6,6 +6,7 @@
 
 #include <mbgl/util/time.hpp>
 #include <mbgl/util/uv.hpp>
+#include <mbgl/util/ptr.hpp>
 
 #include <cstdint>
 #include <map>
@@ -13,7 +14,6 @@
 #include <unordered_map>
 #include <vector>
 #include <set>
-#include <memory>
 
 namespace mbgl {
 
@@ -49,7 +49,7 @@ public:
     const std::string &getSpriteURL() const;
 
 public:
-    std::shared_ptr<StyleLayerGroup> layers;
+    util::ptr<StyleLayerGroup> layers;
     std::vector<std::string> appliedClasses;
     std::string glyph_url;
 
diff --git a/include/mbgl/style/style_bucket.hpp b/include/mbgl/style/style_bucket.hpp
index c2cde52aa5..c4a8f6037e 100644
--- a/include/mbgl/style/style_bucket.hpp
+++ b/include/mbgl/style/style_bucket.hpp
@@ -8,8 +8,8 @@
 #include <mbgl/util/vec.hpp>
 #include <mbgl/util/variant.hpp>
 #include <mbgl/util/noncopyable.hpp>
+#include <mbgl/util/ptr.hpp>
 
-#include <memory>
 #include <forward_list>
 
 namespace mbgl {
@@ -93,12 +93,12 @@ typedef mapbox::util::variant<StyleBucketFill, StyleBucketLine, StyleBucketSymbo
 
 class StyleBucket {
 public:
-    typedef std::shared_ptr<StyleBucket> Ptr;
+    typedef util::ptr<StyleBucket> Ptr;
 
     StyleBucket(StyleLayerType type);
 
     std::string name;
-    std::shared_ptr<StyleSource> style_source;
+    util::ptr<StyleSource> style_source;
     std::string source_layer;
     FilterExpression filter;
     StyleBucketRender render = std::false_type();
diff --git a/include/mbgl/style/style_layer.hpp b/include/mbgl/style/style_layer.hpp
index 84981e3fb4..641dc1e71c 100644
--- a/include/mbgl/style/style_layer.hpp
+++ b/include/mbgl/style/style_layer.hpp
@@ -6,8 +6,9 @@
 #include <mbgl/style/style_properties.hpp>
 #include <mbgl/style/applied_class_properties.hpp>
 
+#include <mbgl/util/ptr.hpp>
+
 #include <vector>
-#include <memory>
 #include <string>
 #include <map>
 #include <set>
@@ -64,7 +65,7 @@ public:
 
     // Bucket information, telling the renderer how to generate the geometries
     // for this layer (feature property filters, tessellation instructions, ...).
-    std::shared_ptr<StyleBucket> bucket;
+    util::ptr<StyleBucket> bucket;
 
     // Contains all style classes that can be applied to this layer.
     const std::map<ClassID, ClassProperties> styles;
@@ -80,7 +81,7 @@ public:
     StyleProperties properties;
 
     // Child layer array (if this layer has child layers).
-    std::shared_ptr<StyleLayerGroup> layers;
+    util::ptr<StyleLayerGroup> layers;
 };
 
 }
diff --git a/include/mbgl/style/style_layer_group.hpp b/include/mbgl/style/style_layer_group.hpp
index 983dd136f0..1af6e23bd7 100644
--- a/include/mbgl/style/style_layer_group.hpp
+++ b/include/mbgl/style/style_layer_group.hpp
@@ -15,7 +15,7 @@ public:
 
     bool hasTransitions() const;
 public:
-    std::vector<std::shared_ptr<StyleLayer>> layers;
+    std::vector<util::ptr<StyleLayer>> layers;
 };
 
 }
diff --git a/include/mbgl/style/style_parser.hpp b/include/mbgl/style/style_parser.hpp
index e4e1b7f632..fc253bb1dd 100644
--- a/include/mbgl/style/style_parser.hpp
+++ b/include/mbgl/style/style_parser.hpp
@@ -27,7 +27,7 @@ public:
 
     void parse(JSVal document);
 
-    std::shared_ptr<StyleLayerGroup> getLayers() {
+    util::ptr<StyleLayerGroup> getLayers() {
         return root;
     }
 
@@ -46,14 +46,14 @@ private:
     void parseSources(JSVal value);
 
     std::unique_ptr<StyleLayerGroup> createLayers(JSVal value);
-    std::shared_ptr<StyleLayer> createLayer(JSVal value);
+    util::ptr<StyleLayer> createLayer(JSVal value);
     void parseLayers();
-    void parseLayer(std::pair<JSVal, std::shared_ptr<StyleLayer>> &pair);
+    void parseLayer(std::pair<JSVal, util::ptr<StyleLayer>> &pair);
     void parseStyles(JSVal value, std::map<ClassID, ClassProperties> &styles);
     void parseStyle(JSVal, ClassProperties &properties);
-    void parseReference(JSVal value, std::shared_ptr<StyleLayer> &layer);
-    void parseBucket(JSVal value, std::shared_ptr<StyleLayer> &layer);
-    void parseRender(JSVal value, std::shared_ptr<StyleLayer> &layer);
+    void parseReference(JSVal value, util::ptr<StyleLayer> &layer);
+    void parseBucket(JSVal value, util::ptr<StyleLayer> &layer);
+    void parseRender(JSVal value, util::ptr<StyleLayer> &layer);
     void parseSprite(JSVal value);
     void parseGlyphURL(JSVal value);
 
@@ -94,13 +94,13 @@ private:
 private:
     std::unordered_map<std::string, const rapidjson::Value *> constants;
 
-    std::unordered_map<std::string, const std::shared_ptr<StyleSource>> sources;
+    std::unordered_map<std::string, const util::ptr<StyleSource>> sources;
 
     // This stores the root layer.
-    std::shared_ptr<StyleLayerGroup> root;
+    util::ptr<StyleLayerGroup> root;
 
     // This maps ids to Layer objects, with all items being at the root level.
-    std::unordered_map<std::string, std::pair<JSVal, std::shared_ptr<StyleLayer>>> layers;
+    std::unordered_map<std::string, std::pair<JSVal, util::ptr<StyleLayer>>> layers;
 
     // Store a stack of layers we're parsing right now. This is to prevent reference cycles.
     std::forward_list<StyleLayer *> stack;
diff --git a/include/mbgl/style/style_source.hpp b/include/mbgl/style/style_source.hpp
index b598550c65..00c48431a1 100644
--- a/include/mbgl/style/style_source.hpp
+++ b/include/mbgl/style/style_source.hpp
@@ -2,18 +2,18 @@
 #define MBGL_STYLE_STYLE_SOURCE
 
 #include <mbgl/style/types.hpp>
+#include <mbgl/util/ptr.hpp>
+#include <mbgl/util/noncopyable.hpp>
+#include <rapidjson/document.h>
 
-#include <memory>
 #include <vector>
 #include <string>
 
-#include <rapidjson/document.h>
-
 namespace mbgl {
 
 class Source;
 
-class SourceInfo {
+class SourceInfo : private util::noncopyable {
 public:
     SourceType type = SourceType::Vector;
     std::string url;
@@ -31,12 +31,12 @@ public:
 
 class StyleSource : public std::enable_shared_from_this<StyleSource> {
 public:
-    SourceInfo info;
+    util::ptr<SourceInfo> info;
 
     bool enabled = false;
-    std::shared_ptr<Source> source;
+    util::ptr<Source> source;
 
-    StyleSource(const SourceInfo &info)
+    StyleSource(const util::ptr<SourceInfo> &info)
         : info(info)
     {}
 };
diff --git a/include/mbgl/text/glyph_store.hpp b/include/mbgl/text/glyph_store.hpp
index e0c0391c73..f8a7cb4d0c 100644
--- a/include/mbgl/text/glyph_store.hpp
+++ b/include/mbgl/text/glyph_store.hpp
@@ -4,6 +4,7 @@
 #include <mbgl/text/glyph.hpp>
 #include <mbgl/util/pbf.hpp>
 #include <mbgl/util/vec.hpp>
+#include <mbgl/util/ptr.hpp>
 
 #include <cstdint>
 #include <vector>
@@ -47,8 +48,15 @@ private:
 
 class GlyphPBF {
 public:
-    GlyphPBF(const std::string &glyphURL, const std::string &fontStack, GlyphRange glyphRange, const std::shared_ptr<FileSource> &fileSource);
+    GlyphPBF(const std::string &glyphURL, const std::string &fontStack, GlyphRange glyphRange, const util::ptr<FileSource> &fileSource);
 
+private:
+    GlyphPBF(const GlyphPBF &) = delete;
+    GlyphPBF(GlyphPBF &&) = delete;
+    GlyphPBF &operator=(const GlyphPBF &) = delete;
+    GlyphPBF &operator=(GlyphPBF &&) = delete;
+
+public:
     void parse(FontStack &stack);
 
     std::shared_future<GlyphPBF &> getFuture();
@@ -63,7 +71,7 @@ private:
 // Manages Glyphrange PBF loading.
 class GlyphStore {
 public:
-    GlyphStore(const std::shared_ptr<FileSource> &fileSource);
+    GlyphStore(const util::ptr<FileSource> &fileSource);
 
     // Block until all specified GlyphRanges of the specified font stack are loaded.
     void waitForGlyphRanges(const std::string &fontStack, const std::set<GlyphRange> &glyphRanges);
@@ -82,7 +90,7 @@ public:
     std::string glyphURL;
 
 private:
-    const std::shared_ptr<FileSource> fileSource;
+    const util::ptr<FileSource> fileSource;
     std::unordered_map<std::string, std::map<GlyphRange, std::unique_ptr<GlyphPBF>>> ranges;
     std::unordered_map<std::string, std::unique_ptr<FontStack>> stacks;
     std::mutex mtx;
diff --git a/include/mbgl/util/compression.hpp b/include/mbgl/util/compression.hpp
new file mode 100644
index 0000000000..a33b2476a7
--- /dev/null
+++ b/include/mbgl/util/compression.hpp
@@ -0,0 +1,15 @@
+#ifndef MBGL_UTIL_COMPRESSION
+#define MBGL_UTIL_COMPRESSION
+
+#include <string>
+
+namespace mbgl {
+namespace util {
+
+std::string compress(const std::string &raw);
+std::string decompress(const std::string &raw);
+
+}
+}
+
+#endif
diff --git a/include/mbgl/util/filesource.hpp b/include/mbgl/util/filesource.hpp
deleted file mode 100644
index 18c63ddfeb..0000000000
--- a/include/mbgl/util/filesource.hpp
+++ /dev/null
@@ -1,43 +0,0 @@
-#ifndef MBGL_UTIL_FILESOURCE
-#define MBGL_UTIL_FILESOURCE
-
-#include <mbgl/util/uv.hpp>
-
-#include <string>
-#include <memory>
-#include <functional>
-
-namespace mbgl {
-
-namespace platform {
-struct Response;
-}
-
-enum class ResourceType : uint8_t {
-    Unknown,
-    Tile,
-    Glyphs,
-    Image,
-    JSON
-};
-
-class FileSource {
-public:
-    FileSource();
-
-    void setBase(const std::string &value);
-    const std::string &getBase() const;
-
-    void load(ResourceType type, const std::string &url, std::function<void(platform::Response *)> callback, const std::shared_ptr<uv::loop> loop = nullptr);
-
-private:
-    // Stores a URL that is used as a base for loading resources with relative path.
-    std::string base;
-
-    // Stores the absolute path to the cache directory.
-    const std::string cache;
-};
-
-}
-
-#endif
diff --git a/include/mbgl/util/interpolate.hpp b/include/mbgl/util/interpolate.hpp
index e8c3389350..c9232db4eb 100644
--- a/include/mbgl/util/interpolate.hpp
+++ b/include/mbgl/util/interpolate.hpp
@@ -1,6 +1,8 @@
 #ifndef MBGL_UTIL_INTERPOLATE
 #define MBGL_UTIL_INTERPOLATE
 
+#include <array>
+
 namespace mbgl {
 namespace util {
 
diff --git a/include/mbgl/util/parsedate.h b/include/mbgl/util/parsedate.h
new file mode 100644
index 0000000000..6905e361d4
--- /dev/null
+++ b/include/mbgl/util/parsedate.h
@@ -0,0 +1,38 @@
+#ifndef HEADER_PARSEDATE_H
+#define HEADER_PARSEDATE_H
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2011, Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at http://curl.haxx.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ***************************************************************************/
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <time.h>
+
+time_t parse_date(const char *p);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* HEADER_PARSEDATE_H */
diff --git a/include/mbgl/util/ptr.hpp b/include/mbgl/util/ptr.hpp
new file mode 100644
index 0000000000..6e02f956f3
--- /dev/null
+++ b/include/mbgl/util/ptr.hpp
@@ -0,0 +1,29 @@
+#ifndef MBGL_UTIL_PTR
+#define MBGL_UTIL_PTR
+
+#include <memory>
+#include <cassert>
+
+namespace mbgl {
+namespace util {
+
+template <typename T>
+class ptr : public ::std::shared_ptr<T> {
+public:
+    template <typename... Args>
+    inline ptr(Args &&... args)
+        : ::std::shared_ptr<T>(::std::forward<Args>(args)...) {}
+
+    inline auto operator->() const -> decltype(this->::std::shared_ptr<T>::operator->()) {
+        assert(*this);
+        return ::std::shared_ptr<T>::operator->();
+    }
+    inline auto operator*() const -> decltype(this->::std::shared_ptr<T>::operator*()) {
+        assert(*this);
+        return ::std::shared_ptr<T>::operator*();
+    }
+};
+}
+}
+
+#endif
\ No newline at end of file
diff --git a/include/mbgl/util/queue.h b/include/mbgl/util/queue.h
new file mode 100644
index 0000000000..fe02b454ea
--- /dev/null
+++ b/include/mbgl/util/queue.h
@@ -0,0 +1,92 @@
+/* Copyright (c) 2013, Ben Noordhuis <info@bnoordhuis.nl>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#ifndef QUEUE_H_
+#define QUEUE_H_
+
+typedef void *QUEUE[2];
+
+/* Private macros. */
+#define QUEUE_NEXT(q)       (*(QUEUE **) &((*(q))[0]))
+#define QUEUE_PREV(q)       (*(QUEUE **) &((*(q))[1]))
+#define QUEUE_PREV_NEXT(q)  (QUEUE_NEXT(QUEUE_PREV(q)))
+#define QUEUE_NEXT_PREV(q)  (QUEUE_PREV(QUEUE_NEXT(q)))
+
+/* Public macros. */
+#define QUEUE_DATA(ptr, type, field)                                          \
+  ((type *) ((char *) (ptr) - ((char *) &((type *) 0)->field)))
+
+#define QUEUE_FOREACH(q, h)                                                   \
+  for ((q) = QUEUE_NEXT(h); (q) != (h); (q) = QUEUE_NEXT(q))
+
+#define QUEUE_EMPTY(q)                                                        \
+  ((const QUEUE *) (q) == (const QUEUE *) QUEUE_NEXT(q))
+
+#define QUEUE_HEAD(q)                                                         \
+  (QUEUE_NEXT(q))
+
+#define QUEUE_INIT(q)                                                         \
+  do {                                                                        \
+    QUEUE_NEXT(q) = (q);                                                      \
+    QUEUE_PREV(q) = (q);                                                      \
+  }                                                                           \
+  while (0)
+
+#define QUEUE_ADD(h, n)                                                       \
+  do {                                                                        \
+    QUEUE_PREV_NEXT(h) = QUEUE_NEXT(n);                                       \
+    QUEUE_NEXT_PREV(n) = QUEUE_PREV(h);                                       \
+    QUEUE_PREV(h) = QUEUE_PREV(n);                                            \
+    QUEUE_PREV_NEXT(h) = (h);                                                 \
+  }                                                                           \
+  while (0)
+
+#define QUEUE_SPLIT(h, q, n)                                                  \
+  do {                                                                        \
+    QUEUE_PREV(n) = QUEUE_PREV(h);                                            \
+    QUEUE_PREV_NEXT(n) = (n);                                                 \
+    QUEUE_NEXT(n) = (q);                                                      \
+    QUEUE_PREV(h) = QUEUE_PREV(q);                                            \
+    QUEUE_PREV_NEXT(h) = (h);                                                 \
+    QUEUE_PREV(q) = (n);                                                      \
+  }                                                                           \
+  while (0)
+
+#define QUEUE_INSERT_HEAD(h, q)                                               \
+  do {                                                                        \
+    QUEUE_NEXT(q) = QUEUE_NEXT(h);                                            \
+    QUEUE_PREV(q) = (h);                                                      \
+    QUEUE_NEXT_PREV(q) = (q);                                                 \
+    QUEUE_NEXT(h) = (q);                                                      \
+  }                                                                           \
+  while (0)
+
+#define QUEUE_INSERT_TAIL(h, q)                                               \
+  do {                                                                        \
+    QUEUE_NEXT(q) = (h);                                                      \
+    QUEUE_PREV(q) = QUEUE_PREV(h);                                            \
+    QUEUE_PREV_NEXT(q) = (q);                                                 \
+    QUEUE_PREV(h) = (q);                                                      \
+  }                                                                           \
+  while (0)
+
+#define QUEUE_REMOVE(q)                                                       \
+  do {                                                                        \
+    QUEUE_PREV_NEXT(q) = QUEUE_NEXT(q);                                       \
+    QUEUE_NEXT_PREV(q) = QUEUE_PREV(q);                                       \
+  }                                                                           \
+  while (0)
+
+#endif /* QUEUE_H_ */
diff --git a/include/mbgl/util/raster.hpp b/include/mbgl/util/raster.hpp
index e526ffa5ac..7051c30091 100644
--- a/include/mbgl/util/raster.hpp
+++ b/include/mbgl/util/raster.hpp
@@ -4,11 +4,11 @@
 #include <mbgl/util/transition.hpp>
 #include <mbgl/util/texturepool.hpp>
 #include <mbgl/util/image.hpp>
+#include <mbgl/util/ptr.hpp>
 #include <mbgl/renderer/prerendered_texture.hpp>
 
 #include <string>
 #include <mutex>
-#include <memory>
 
 typedef struct uv_loop_s uv_loop_t;
 
@@ -17,7 +17,7 @@ namespace mbgl {
 class Raster : public std::enable_shared_from_this<Raster> {
 
 public:
-    Raster(const std::shared_ptr<Texturepool> &texturepool);
+    Raster(const util::ptr<Texturepool> &texturepool);
     ~Raster();
 
     // load image data
@@ -57,7 +57,7 @@ private:
     bool loaded = false;
 
     // shared texture pool
-    std::shared_ptr<Texturepool> texturepool;
+    util::ptr<Texturepool> texturepool;
 
     // min/mag filter
     uint32_t filter = 0;
@@ -66,7 +66,7 @@ private:
     std::unique_ptr<util::Image> img;
 
     // fade in transition
-    std::shared_ptr<util::transition> fade_transition = nullptr;
+    util::ptr<util::transition> fade_transition = nullptr;
 };
 
 }
diff --git a/include/mbgl/util/sqlite3.hpp b/include/mbgl/util/sqlite3.hpp
new file mode 100644
index 0000000000..3e324f7ce1
--- /dev/null
+++ b/include/mbgl/util/sqlite3.hpp
@@ -0,0 +1,74 @@
+#pragma once
+
+#include <string>
+#include <stdexcept>
+
+typedef struct sqlite3 sqlite3;
+typedef struct sqlite3_stmt sqlite3_stmt;
+
+namespace mapbox {
+namespace sqlite {
+
+enum OpenFlag : int {
+    ReadOnly = 0x00000001,
+    ReadWrite = 0x00000002,
+    Create = 0x00000004,
+    NoMutex = 0x00008000,
+    FullMutex = 0x00010000,
+    SharedCache = 0x00020000,
+    PrivateCache = 0x00040000,
+};
+
+struct Exception : std::runtime_error {
+    inline Exception(int err, const char *msg) : std::runtime_error(msg), code(err) {}
+    const int code = 0;
+};
+
+class Statement;
+
+class Database {
+private:
+    Database(const Database &) = delete;
+    Database &operator=(const Database &) = delete;
+
+public:
+    Database(const std::string &filename, int flags = 0);
+    Database(Database &&);
+    ~Database();
+    Database &operator=(Database &&);
+
+    operator bool() const;
+
+    void exec(const std::string &sql);
+    Statement prepare(const char *query);
+
+private:
+    sqlite3 *db = nullptr;
+};
+
+class Statement {
+private:
+    Statement(const Statement &) = delete;
+    Statement &operator=(const Statement &) = delete;
+
+public:
+    Statement(sqlite3 *db, const char *sql);
+    Statement(Statement &&);
+    ~Statement();
+    Statement &operator=(Statement &&);
+
+    operator bool() const;
+
+    template <typename T> void bind(int offset, T value);
+    void bind(int offset, const std::string &value, bool retain = true);
+    template <typename T> T get(int offset);
+
+    bool run();
+    void reset();
+
+private:
+    sqlite3_stmt *stmt = nullptr;
+};
+
+}
+}
diff --git a/include/mbgl/util/uv-channel.h b/include/mbgl/util/uv-channel.h
new file mode 100644
index 0000000000..ea5c279f65
--- /dev/null
+++ b/include/mbgl/util/uv-channel.h
@@ -0,0 +1,29 @@
+#ifndef MBGL_UTIL_UV_CHANNEL
+#define MBGL_UTIL_UV_CHANNEL
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <uv.h>
+
+// Taken from http://navaneeth.github.io/blog/2013/08/02/channels-in-libuv/
+
+typedef struct uv_chan_s uv_chan_t;
+
+struct uv_chan_s {
+    uv_mutex_t mutex;
+    uv_cond_t cond;
+    void *q[2];
+};
+
+int uv_chan_init(uv_chan_t *chan);
+void uv_chan_send(uv_chan_t *chan, void *data);
+void *uv_chan_receive(uv_chan_t *chan);
+void uv_chan_destroy(uv_chan_t *chan);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/include/mbgl/util/uv-messenger.h b/include/mbgl/util/uv-messenger.h
new file mode 100644
index 0000000000..82b8ef2d9c
--- /dev/null
+++ b/include/mbgl/util/uv-messenger.h
@@ -0,0 +1,32 @@
+#ifndef MBGL_UTIL_UV_MESSENGER
+#define MBGL_UTIL_UV_MESSENGER
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <uv.h>
+
+typedef struct uv_messenger_s uv_messenger_t;
+typedef void (*uv_messenger_cb)(void *arg);
+typedef void (*uv_messenger_stop_cb)(uv_messenger_t *msgr);
+
+struct uv_messenger_s {
+    uv_mutex_t mutex;
+    uv_async_t async;
+    uv_messenger_cb callback;
+    void *data;
+    void *queue[2];
+};
+
+int uv_messenger_init(uv_loop_t *loop, uv_messenger_t *msgr, uv_messenger_cb callback);
+void uv_messenger_send(uv_messenger_t *msgr, void *arg);
+void uv_messenger_stop(uv_messenger_t *msgr);
+void uv_messenger_ref(uv_messenger_t *msgr);
+void uv_messenger_unref(uv_messenger_t *msgr);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/include/mbgl/util/uv-worker.h b/include/mbgl/util/uv-worker.h
new file mode 100644
index 0000000000..451b6fb04d
--- /dev/null
+++ b/include/mbgl/util/uv-worker.h
@@ -0,0 +1,42 @@
+#ifndef MBGL_UTIL_UV_WORKER
+#define MBGL_UTIL_UV_WORKER
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct uv_messenger_s uv_messenger_t;
+
+#include <mbgl/util/uv-channel.h>
+
+#include <stdlib.h>
+
+typedef struct uv_worker_s uv_worker_t;
+
+typedef void (*uv_worker_cb)(void *data);
+typedef void (*uv_worker_after_cb)(void *data);
+typedef void (*uv_worker_close_cb)(uv_worker_t *worker);
+
+struct uv_worker_s {
+#ifndef NDEBUG
+    unsigned long thread_id;
+#endif
+    uv_loop_t *loop;
+    uv_messenger_t *msgr;
+    uv_chan_t chan;
+    const char *name;
+    int count;
+    uv_worker_close_cb close_cb;
+    unsigned int active_items;
+};
+
+int uv_worker_init(uv_worker_t *worker, uv_loop_t *loop, int count, const char *name);
+void uv_worker_send(uv_worker_t *worker, void *data, uv_worker_cb work_cb,
+                    uv_worker_after_cb after_work_cb);
+void uv_worker_close(uv_worker_t *worker, uv_worker_close_cb close_cb);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/include/mbgl/util/uv.hpp b/include/mbgl/util/uv.hpp
index 4ceb8b873f..3c533cfbf8 100644
--- a/include/mbgl/util/uv.hpp
+++ b/include/mbgl/util/uv.hpp
@@ -4,6 +4,7 @@
 #include <string>
 
 typedef struct uv_async_s uv_async_t;
+typedef struct uv_timer_s uv_timer_t;
 typedef struct uv_handle_s uv_handle_t;
 typedef struct uv_loop_s uv_loop_t;
 
@@ -11,9 +12,15 @@ namespace uv {
 
 std::string cwd();
 
+struct deleter {
+    void operator()(uv_async_t *async);
+    void operator()(uv_timer_t *timer);
+};
+
 class thread;
 class rwlock;
 class loop;
+class worker;
 
 }
 
diff --git a/include/mbgl/util/uv_detail.hpp b/include/mbgl/util/uv_detail.hpp
index b3fdbb3719..a80423f822 100644
--- a/include/mbgl/util/uv_detail.hpp
+++ b/include/mbgl/util/uv_detail.hpp
@@ -1,21 +1,13 @@
 #ifndef MBGL_UTIL_UV_DETAIL
 #define MBGL_UTIL_UV_DETAIL
 
+#include <mbgl/util/ptr.hpp>
+#include <mbgl/util/uv-worker.h>
+
 #include <uv.h>
+
 #include <functional>
 #include <cassert>
-
-#ifdef __clang__
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wunused-parameter"
-#endif
-
-#include <boost/lockfree/queue.hpp>
-
-#ifdef __clang__
-#pragma clang diagnostic pop
-#endif
-
 #include <string>
 
 
@@ -112,6 +104,24 @@ private:
     uv_once_t o = UV_ONCE_INIT;
 };
 
+class worker {
+public:
+    inline worker(uv_loop_t *loop, unsigned int count, const char *name = nullptr) : w(new uv_worker_t) {
+        uv_worker_init(w, loop, count, name);
+    }
+    inline ~worker() {
+        uv_worker_close(w, [](uv_worker_t *worker) {
+            delete worker;
+        });
+    }
+    inline void add(void *data, uv_worker_cb work_cb, uv_worker_after_cb after_work_cb) {
+        uv_worker_send(w, data, work_cb, after_work_cb);
+    }
+
+private:
+    uv_worker_t *w;
+};
+
 template <typename T>
 class work {
 public:
@@ -119,30 +129,26 @@ public:
     typedef void (*after_work_callback)(T &object);
 
     template<typename... Args>
-    work(const std::shared_ptr<loop> &loop, work_callback work_cb, after_work_callback after_work_cb, Args&&... args)
-        : loop(loop),
-          data(std::forward<Args>(args)...),
+    work(worker &worker, work_callback work_cb, after_work_callback after_work_cb, Args&&... args)
+        : data(std::forward<Args>(args)...),
           work_cb(work_cb),
           after_work_cb(after_work_cb) {
-        req.data = this;
-        uv_queue_work(**loop, &req, do_work, after_work);
+        worker.add(this, do_work, after_work);
     }
 
 private:
-    static void do_work(uv_work_t *req) {
-        work<T> *w = static_cast<work<T> *>(req->data);
+    static void do_work(void *data) {
+        work<T> *w = reinterpret_cast<work<T> *>(data);
         w->work_cb(w->data);
     }
 
-    static void after_work(uv_work_t *req, int) {
-        work<T> *w = static_cast<work<T> *>(req->data);
+    static void after_work(void *data) {
+        work<T> *w = reinterpret_cast<work<T> *>(data);
         w->after_work_cb(w->data);
         delete w;
     }
 
 private:
-    std::shared_ptr<uv::loop> loop;
-    uv_work_t req;
     T data;
     work_callback work_cb;
     after_work_callback after_work_cb;