diff --git a/routing_algorithms/map_matching.hpp b/routing_algorithms/map_matching.hpp
index 4246539ef..89c4e357c 100644
--- a/routing_algorithms/map_matching.hpp
+++ b/routing_algorithms/map_matching.hpp
@@ -272,7 +272,7 @@ class MapMatching final : public BasicRoutingInterface<DataFacadeT, MapMatching<
             while (parent_timestamp_index >= sub_matching_begin &&
                    model.breakage[parent_timestamp_index])
             {
-                parent_timestamp_index--;
+                --parent_timestamp_index;
             }
 
             // matchings that only consist of one candidate are invalid
diff --git a/server/api_grammar.hpp b/server/api_grammar.hpp
index 5c7dcde45..a629cfbf7 100644
--- a/server/api_grammar.hpp
+++ b/server/api_grammar.hpp
@@ -65,12 +65,6 @@ template <typename Iterator, class HandlerT> struct APIGrammar : qi::grammar<Ite
                stringwithDot[boost::bind(&HandlerT::addHint, handler, ::_1)];
         timestamp = (-qi::lit('&')) >> qi::lit("t") >> '=' >>
                qi::uint_[boost::bind(&HandlerT::addTimestamp, handler, ::_1)];
-        matching_beta = (-qi::lit('&')) >> qi::lit("matching_beta") >> '=' >>
-               qi::short_[boost::bind(&HandlerT::setMatchingBeta, handler, ::_1)];
-        gps_precision = (-qi::lit('&')) >> qi::lit("gps_precision") >> '=' >>
-               qi::short_[boost::bind(&HandlerT::setGPSPrecision, handler, ::_1)];
-        classify = (-qi::lit('&')) >> qi::lit("classify") >> '=' >>
-            qi::bool_[boost::bind(&HandlerT::setClassify, handler, ::_1)];
         u = (-qi::lit('&')) >> qi::lit("u") >> '=' >>
             qi::bool_[boost::bind(&HandlerT::setUTurn, handler, ::_1)];
         uturns = (-qi::lit('&')) >> qi::lit("uturns") >> '=' >>
@@ -83,6 +77,12 @@ template <typename Iterator, class HandlerT> struct APIGrammar : qi::grammar<Ite
                   string[boost::bind(&HandlerT::setDeprecatedAPIFlag, handler, ::_1)];
         num_results = (-qi::lit('&')) >> qi::lit("num_results") >> '=' >>
                       qi::short_[boost::bind(&HandlerT::setNumberOfResults, handler, ::_1)];
+        matching_beta = (-qi::lit('&')) >> qi::lit("matching_beta") >> '=' >>
+               qi::short_[boost::bind(&HandlerT::setMatchingBeta, handler, ::_1)];
+        gps_precision = (-qi::lit('&')) >> qi::lit("gps_precision") >> '=' >>
+               qi::short_[boost::bind(&HandlerT::setGPSPrecision, handler, ::_1)];
+        classify = (-qi::lit('&')) >> qi::lit("classify") >> '=' >>
+            qi::bool_[boost::bind(&HandlerT::setClassify, handler, ::_1)];
 
         string = +(qi::char_("a-zA-Z"));
         stringwithDot = +(qi::char_("a-zA-Z0-9_.-"));
@@ -92,8 +92,8 @@ template <typename Iterator, class HandlerT> struct APIGrammar : qi::grammar<Ite
 
     qi::rule<Iterator> api_call, query;
     qi::rule<Iterator, std::string()> service, zoom, output, string, jsonp, checksum, location,
-        hint, timestamp, matching_beta, gps_precision, classify, stringwithDot, stringwithPercent, language, instruction, geometry, cmp, alt_route, u,
-        uturns, old_API, num_results;
+        hint, timestamp, stringwithDot, stringwithPercent, language, instruction, geometry, cmp, alt_route, u,
+        uturns, old_API, num_results, matching_beta, gps_precision, classify;
 
     HandlerT *handler;
 };
diff --git a/util/json_logger.hpp b/util/json_logger.hpp
index 872a926d5..03f8a171a 100644
--- a/util/json_logger.hpp
+++ b/util/json_logger.hpp
@@ -1,6 +1,6 @@
 /*
 
-Copyright (c) 2015, Project OSRM, Dennis Luxen, others
+Copyright (c) 2015, Project OSRM contributors
 All rights reserved.
 
 Redistribution and use in source and binary forms, with or without modification,
@@ -37,6 +37,8 @@ namespace osrm
 namespace json
 {
 
+// Used to append additional debugging information to the JSON response in a
+// thread safe manner.
 class Logger
 {
     using MapT = std::unordered_map<std::string, osrm::json::Value>;
@@ -74,4 +76,4 @@ class Logger
 }
 }
 
-#endif /* SIMPLE_LOGGER_HPP */
+#endif /* JSON_LOGGER_HPP */
diff --git a/util/json_util.hpp b/util/json_util.hpp
index 461148ea3..bfb8a8bc4 100644
--- a/util/json_util.hpp
+++ b/util/json_util.hpp
@@ -30,8 +30,8 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #include <osrm/json_container.hpp>
 
-#include <limits>
 #include <cmath>
+#include <limits>
 
 namespace osrm
 {
@@ -53,18 +53,10 @@ template <typename T> T clamp_float(T d)
     return d;
 }
 
-void append_to_array(osrm::json::Array &a) {}
-template <typename T, typename... Args>
-void append_to_array(osrm::json::Array &a, T value, Args... args)
-{
-    a.values.emplace_back(value);
-    append_to_array(a, args...);
-}
-
 template <typename... Args> osrm::json::Array make_array(Args... args)
 {
     osrm::json::Array a;
-    append_to_array(a, args...);
+    append_to_container(a.values, args...);
     return a;
 }