diff --git a/bin/offline.cpp b/bin/offline.cpp
index 5123e7b92..0d0fe5728 100644
--- a/bin/offline.cpp
+++ b/bin/offline.cpp
@@ -53,6 +53,27 @@ mapbox::geometry::geometry<double> parseGeometry(const std::string& json) {
         });
 }
 
+std::ostream& operator<<(std::ostream& os, mbgl::Response::Error::Reason r) {
+    switch (r) {
+    case mbgl::Response::Error::Reason::Success:
+        return os << "Response::Error::Reason::Success";
+    case mbgl::Response::Error::Reason::NotFound:
+        return os << "Response::Error::Reason::NotFound";
+    case mbgl::Response::Error::Reason::Server:
+        return os << "Response::Error::Reason::Server";
+    case mbgl::Response::Error::Reason::Connection:
+        return os << "Response::Error::Reason::Connection";
+    case mbgl::Response::Error::Reason::RateLimit:
+        return os << "Response::Error::Reason::RateLimit";
+    case mbgl::Response::Error::Reason::Other:
+        return os << "Response::Error::Reason::Other";
+    }
+
+    // The above switch is exhaustive, but placate GCC nonetheless:
+    assert(false);
+    return os;
+}
+
 int main(int argc, char *argv[]) {
     args::ArgumentParser argumentParser("Mapbox GL offline tool");
     args::HelpFlag helpFlag(argumentParser, "help", "Display this help menu", {'h', "help"});
diff --git a/cmake/core-files.txt b/cmake/core-files.txt
index 9e83ceb66..e7fd7d81c 100644
--- a/cmake/core-files.txt
+++ b/cmake/core-files.txt
@@ -752,6 +752,7 @@ src/mbgl/util/math.hpp
 src/mbgl/util/offscreen_texture.cpp
 src/mbgl/util/offscreen_texture.hpp
 src/mbgl/util/premultiply.cpp
+src/mbgl/util/rapidjson.cpp
 src/mbgl/util/rapidjson.hpp
 src/mbgl/util/rect.hpp
 src/mbgl/util/std.hpp
diff --git a/include/mbgl/storage/response.hpp b/include/mbgl/storage/response.hpp
index 508400141..07b059e43 100644
--- a/include/mbgl/storage/response.hpp
+++ b/include/mbgl/storage/response.hpp
@@ -69,6 +69,4 @@ public:
     Error(Reason, std::string = "", optional<Timestamp> = {});
 };
 
-std::ostream& operator<<(std::ostream&, Response::Error::Reason);
-
 } // namespace mbgl
diff --git a/platform/android/src/conversion/constant.cpp b/platform/android/src/conversion/constant.cpp
index eaff434db..a609dc7c6 100644
--- a/platform/android/src/conversion/constant.cpp
+++ b/platform/android/src/conversion/constant.cpp
@@ -1,7 +1,7 @@
 #include "constant.hpp"
 #include "collection.hpp"
 
-#include <sstream>
+#include <mbgl/util/string.hpp>
 
 namespace mbgl {
 namespace android {
@@ -24,9 +24,18 @@ Result<jni::Local<jni::Object<>>> Converter<jni::Local<jni::Object<>>, std::stri
 }
 
 Result<jni::Local<jni::Object<>>> Converter<jni::Local<jni::Object<>>, Color>::operator()(jni::JNIEnv& env, const Color& value) const {
-    std::stringstream sstream;
-    sstream << "rgba(" << value.r << ", " << value.g << ", " << value.b << ", "  << value.a << ")";
-    return jni::Make<jni::String>(env, sstream.str());
+    std::string result;
+    result.reserve(32);
+    result += "rgba(";
+    result += util::toString(value.r);
+    result += ", ";
+    result += util::toString(value.g);
+    result += ", ";
+    result += util::toString(value.b);
+    result += ", ";
+    result += util::toString(value.a);
+    result += ")";
+    return jni::Make<jni::String>(env, result);
 }
 
 Result<jni::Local<jni::Object<>>> Converter<jni::Local<jni::Object<>>, style::expression::Formatted>::operator()(jni::JNIEnv& env, const style::expression::Formatted& value) const {
diff --git a/platform/node/test/js/map.test.js b/platform/node/test/js/map.test.js
index 4a71d7204..b21c1519e 100644
--- a/platform/node/test/js/map.test.js
+++ b/platform/node/test/js/map.test.js
@@ -317,7 +317,7 @@ test('Map', function(t) {
 
             t.throws(function() {
                 map.load('foo bar');
-            }, /Failed to parse style: 1 - Invalid value./);
+            }, /Failed to parse style: Invalid value. at offset 1/);
 
             t.throws(function() {
                 map.load('""');
@@ -349,7 +349,7 @@ test('Map', function(t) {
 
             t.throws(function() {
                 map.load('invalid');
-            }, /Failed to parse style: 0 - Invalid value./);
+            }, /Failed to parse style: Invalid value. at offset 0/);
         });
 
         t.test('accepts an empty stylesheet string', function(t) {
diff --git a/src/mbgl/algorithm/generate_clip_ids.cpp b/src/mbgl/algorithm/generate_clip_ids.cpp
index 287d2a408..aefa55b92 100644
--- a/src/mbgl/algorithm/generate_clip_ids.cpp
+++ b/src/mbgl/algorithm/generate_clip_ids.cpp
@@ -7,7 +7,6 @@
 #include <vector>
 #include <bitset>
 #include <cassert>
-#include <iostream>
 #include <algorithm>
 #include <iterator>
 
diff --git a/src/mbgl/geometry/line_atlas.cpp b/src/mbgl/geometry/line_atlas.cpp
index ba14655ca..1bd6f987e 100644
--- a/src/mbgl/geometry/line_atlas.cpp
+++ b/src/mbgl/geometry/line_atlas.cpp
@@ -4,7 +4,6 @@
 #include <mbgl/util/platform.hpp>
 #include <mbgl/util/hash.hpp>
 
-#include <sstream>
 #include <cmath>
 
 namespace mbgl {
diff --git a/src/mbgl/renderer/sources/render_raster_dem_source.cpp b/src/mbgl/renderer/sources/render_raster_dem_source.cpp
index fbf2c09d1..2283a0e78 100644
--- a/src/mbgl/renderer/sources/render_raster_dem_source.cpp
+++ b/src/mbgl/renderer/sources/render_raster_dem_source.cpp
@@ -4,7 +4,6 @@
 #include <mbgl/algorithm/update_tile_masks.hpp>
 #include <mbgl/geometry/dem_data.hpp>
 #include <mbgl/renderer/buckets/hillshade_bucket.hpp>
-#include <iostream>
 
 namespace mbgl {
 
diff --git a/src/mbgl/sprite/sprite_parser.cpp b/src/mbgl/sprite/sprite_parser.cpp
index 1a36e3e99..99e2b0c8c 100644
--- a/src/mbgl/sprite/sprite_parser.cpp
+++ b/src/mbgl/sprite/sprite_parser.cpp
@@ -9,7 +9,6 @@
 
 #include <cmath>
 #include <limits>
-#include <sstream>
 
 namespace mbgl {
 
@@ -91,9 +90,7 @@ std::vector<std::unique_ptr<style::Image>> parseSprite(const std::string& encode
     JSDocument doc;
     doc.Parse<0>(json.c_str());
     if (doc.HasParseError()) {
-        std::stringstream message;
-        message << "Failed to parse JSON: " << rapidjson::GetParseError_En(doc.GetParseError()) << " at offset " << doc.GetErrorOffset();
-        throw std::runtime_error(message.str());
+        throw std::runtime_error("Failed to parse JSON: " + formatJSONParseError(doc));
     } else if (!doc.IsObject()) {
         throw std::runtime_error("Sprite JSON root must be an object");
     } else {
diff --git a/src/mbgl/storage/response.cpp b/src/mbgl/storage/response.cpp
index 222f55db8..ba075c326 100644
--- a/src/mbgl/storage/response.cpp
+++ b/src/mbgl/storage/response.cpp
@@ -1,8 +1,4 @@
 #include <mbgl/storage/response.hpp>
-#include <mbgl/util/chrono.hpp>
-
-#include <iostream>
-#include <cassert>
 
 namespace mbgl {
 
@@ -26,25 +22,4 @@ Response::Error::Error(Reason reason_, std::string message_, optional<Timestamp>
     : reason(reason_), message(std::move(message_)), retryAfter(std::move(retryAfter_)) {
 }
 
-std::ostream& operator<<(std::ostream& os, Response::Error::Reason r) {
-    switch (r) {
-    case Response::Error::Reason::Success:
-        return os << "Response::Error::Reason::Success";
-    case Response::Error::Reason::NotFound:
-        return os << "Response::Error::Reason::NotFound";
-    case Response::Error::Reason::Server:
-        return os << "Response::Error::Reason::Server";
-    case Response::Error::Reason::Connection:
-        return os << "Response::Error::Reason::Connection";
-    case Response::Error::Reason::RateLimit:
-        return os << "Response::Error::Reason::RateLimit";
-    case Response::Error::Reason::Other:
-        return os << "Response::Error::Reason::Other";
-    }
-
-    // The above switch is exhaustive, but placate GCC nonetheless:
-    assert(false);
-    return os;
-}
-
 } // namespace mbgl
diff --git a/src/mbgl/style/conversion/json.hpp b/src/mbgl/style/conversion/json.hpp
index 3a7bf2b55..503f60a38 100644
--- a/src/mbgl/style/conversion/json.hpp
+++ b/src/mbgl/style/conversion/json.hpp
@@ -4,7 +4,6 @@
 #include <mbgl/style/rapidjson_conversion.hpp>
 
 #include <string>
-#include <sstream>
 
 namespace mbgl {
 namespace style {
@@ -16,9 +15,7 @@ optional<T> convertJSON(const std::string& json, Error& error, Args&&...args) {
     document.Parse<0>(json.c_str());
 
     if (document.HasParseError()) {
-        std::stringstream message;
-        message << document.GetErrorOffset() << " - " << rapidjson::GetParseError_En(document.GetParseError());
-        error = { message.str() };
+        error = { formatJSONParseError(document) };
         return {};
     }
 
diff --git a/src/mbgl/style/parser.cpp b/src/mbgl/style/parser.cpp
index 114a666f0..77cf23bad 100644
--- a/src/mbgl/style/parser.cpp
+++ b/src/mbgl/style/parser.cpp
@@ -18,7 +18,6 @@
 
 #include <algorithm>
 #include <set>
-#include <sstream>
 
 namespace mbgl {
 namespace style {
@@ -30,11 +29,7 @@ StyleParseResult Parser::parse(const std::string& json) {
     document.Parse<0>(json.c_str());
 
     if (document.HasParseError()) {
-        std::stringstream message;
-        message <<  document.GetErrorOffset() << " - "
-            << rapidjson::GetParseError_En(document.GetParseError());
-
-        return std::make_exception_ptr(std::runtime_error(message.str()));
+        return std::make_exception_ptr(std::runtime_error(formatJSONParseError(document)));
     }
 
     if (!document.IsObject()) {
diff --git a/src/mbgl/text/shaping.cpp b/src/mbgl/text/shaping.cpp
index 6d10085ad..3a6335955 100644
--- a/src/mbgl/text/shaping.cpp
+++ b/src/mbgl/text/shaping.cpp
@@ -5,6 +5,7 @@
 #include <mbgl/text/bidi.hpp>
 
 #include <algorithm>
+#include <list>
 #include <cmath>
 
 namespace mbgl {
diff --git a/src/mbgl/tile/geometry_tile.cpp b/src/mbgl/tile/geometry_tile.cpp
index 9743cd3f7..80b3e970b 100644
--- a/src/mbgl/tile/geometry_tile.cpp
+++ b/src/mbgl/tile/geometry_tile.cpp
@@ -19,8 +19,6 @@
 #include <mbgl/util/logging.hpp>
 #include <mbgl/actor/scheduler.hpp>
 
-#include <iostream>
-
 namespace mbgl {
 
 using namespace style;
diff --git a/src/mbgl/util/mapbox.cpp b/src/mbgl/util/mapbox.cpp
index b823b727a..6c36c152c 100644
--- a/src/mbgl/util/mapbox.cpp
+++ b/src/mbgl/util/mapbox.cpp
@@ -6,7 +6,6 @@
 
 #include <stdexcept>
 #include <vector>
-#include <iostream>
 #include <cstring>
 
 namespace {
diff --git a/src/mbgl/util/rapidjson.cpp b/src/mbgl/util/rapidjson.cpp
new file mode 100644
index 000000000..32a3c0b92
--- /dev/null
+++ b/src/mbgl/util/rapidjson.cpp
@@ -0,0 +1,13 @@
+#include <mbgl/util/rapidjson.hpp>
+#include <mbgl/util/string.hpp>
+
+namespace mbgl {
+
+std::string formatJSONParseError(const JSDocument& doc) {
+    return std::string{ rapidjson::GetParseError_En(doc.GetParseError()) } + " at offset " +
+           util::toString(doc.GetErrorOffset());
+}
+
+} // namespace mbgl
+
+
diff --git a/src/mbgl/util/rapidjson.hpp b/src/mbgl/util/rapidjson.hpp
index 7262e8545..2fb2a07c9 100644
--- a/src/mbgl/util/rapidjson.hpp
+++ b/src/mbgl/util/rapidjson.hpp
@@ -8,4 +8,6 @@ namespace mbgl {
 using JSDocument = rapidjson::GenericDocument<rapidjson::UTF8<>, rapidjson::CrtAllocator>;
 using JSValue = rapidjson::GenericValue<rapidjson::UTF8<>, rapidjson::CrtAllocator>;
 
+std::string formatJSONParseError(const JSDocument&);
+
 } // namespace mbgl
diff --git a/src/mbgl/util/stopwatch.cpp b/src/mbgl/util/stopwatch.cpp
index 3883d8535..6db9da07e 100644
--- a/src/mbgl/util/stopwatch.cpp
+++ b/src/mbgl/util/stopwatch.cpp
@@ -4,7 +4,6 @@
 #include <mbgl/util/chrono.hpp>
 #include <mbgl/util/logging.hpp>
 
-#include <iostream>
 #include <atomic>
 
 namespace mbgl {
diff --git a/src/mbgl/util/stopwatch.hpp b/src/mbgl/util/stopwatch.hpp
index 0c91342a5..daa313f70 100644
--- a/src/mbgl/util/stopwatch.hpp
+++ b/src/mbgl/util/stopwatch.hpp
@@ -4,7 +4,10 @@
 #include <mbgl/util/chrono.hpp>
 
 #include <string>
+
+#ifdef MBGL_TIMING
 #include <sstream>
+#endif
 
 namespace mbgl {
 namespace util {
diff --git a/test/map/map.test.cpp b/test/map/map.test.cpp
index cd15c5c27..a21f9c7e7 100644
--- a/test/map/map.test.cpp
+++ b/test/map/map.test.cpp
@@ -237,7 +237,7 @@ TEST(Map, SetStyleInvalidJSON) {
     auto observer = Log::removeObserver();
     auto flo = static_cast<FixtureLogObserver*>(observer.get());
     EXPECT_EQ(1u, flo->count({ EventSeverity::Error, Event::ParseStyle, -1,
-        "Failed to parse style: 0 - Invalid value." }));
+        "Failed to parse style: Invalid value. at offset 0" }));
     auto unchecked = flo->unchecked();
     EXPECT_TRUE(unchecked.empty()) << unchecked;
 }
diff --git a/test/style/source.test.cpp b/test/style/source.test.cpp
index 6cb01146f..abd435023 100644
--- a/test/style/source.test.cpp
+++ b/test/style/source.test.cpp
@@ -127,7 +127,7 @@ TEST(Source, LoadingCorrupt) {
 
     test.styleObserver.sourceError = [&] (Source& source, std::exception_ptr error) {
         EXPECT_EQ("source", source.getID());
-        EXPECT_EQ("0 - Invalid value.", util::toString(error));
+        EXPECT_EQ("Invalid value. at offset 0", util::toString(error));
         test.end();
     };