diff --git a/indexer/categories_holder.cpp b/indexer/categories_holder.cpp
index 51ffd6de4f..4c222c9931 100644
--- a/indexer/categories_holder.cpp
+++ b/indexer/categories_holder.cpp
@@ -41,7 +41,7 @@ void CategoriesHolder::AddCategory(Category & cat, vector<uint32_t> & types)
 
     for (size_t i = 0; i < p->m_synonyms.size(); ++i)
     {
-      ASSERT(p->m_synonyms[i].m_locale != UNSUPPORTED_LOCALE_CODE, ());
+      ASSERT(p->m_synonyms[i].m_locale != kUnsupportedLocaleCode, ());
 
       StringT const uniName = search::NormalizeAndSimplifyString(p->m_synonyms[i].m_name);
 
@@ -128,7 +128,7 @@ void CategoriesHolder::LoadFromStream(istream & s)
         }
 
         int8_t const langCode = MapLocaleToInteger(*iter);
-        CHECK(langCode != UNSUPPORTED_LOCALE_CODE, ("Invalid language code:", *iter, "at line:", lineNumber));
+        CHECK(langCode != kUnsupportedLocaleCode, ("Invalid language code:", *iter, "at line:", lineNumber));
 
         while (++iter)
         {
@@ -148,7 +148,7 @@ void CategoriesHolder::LoadFromStream(istream & s)
             name.m_name = name.m_name.substr(1);
           }
           else
-            name.m_prefixLengthToSuggest = Category::EMPTY_PREFIX_LENGTH;
+            name.m_prefixLengthToSuggest = Category::kEmptyPrefixLength;
 
           // Process emoji symbols.
           using namespace strings;
@@ -263,5 +263,5 @@ int8_t CategoriesHolder::MapLocaleToInteger(string const & locale)
     return 17; // Simplified Chinese by default for all other cases
   }
 
-  return UNSUPPORTED_LOCALE_CODE;
+  return kUnsupportedLocaleCode;
 }
diff --git a/indexer/categories_holder.hpp b/indexer/categories_holder.hpp
index feaad857d5..0af32fb181 100644
--- a/indexer/categories_holder.hpp
+++ b/indexer/categories_holder.hpp
@@ -15,7 +15,7 @@ class CategoriesHolder
 public:
   struct Category
   {
-    static const uint8_t EMPTY_PREFIX_LENGTH = 10;
+    static constexpr uint8_t kEmptyPrefixLength = 10;
 
     struct Name
     {
@@ -48,14 +48,14 @@ public:
   void LoadFromStream(istream & s);
 
   template <class ToDo>
-  void ForEachCategory(ToDo toDo) const
+  void ForEachCategory(ToDo && toDo) const
   {
     for (IteratorT i = m_type2cat.begin(); i != m_type2cat.end(); ++i)
       toDo(*i->second);
   }
 
   template <class ToDo>
-  void ForEachName(ToDo toDo) const
+  void ForEachName(ToDo && toDo) const
   {
     for (IteratorT i = m_type2cat.begin(); i != m_type2cat.end(); ++i)
       for (size_t j = 0; j < i->second->m_synonyms.size(); ++j)
@@ -63,7 +63,7 @@ public:
   }
 
   template <class ToDo>
-  void ForEachTypeByName(int8_t locale, StringT const & name, ToDo toDo) const
+  void ForEachTypeByName(int8_t locale, StringT const & name, ToDo && toDo) const
   {
     typedef typename Name2CatContT::const_iterator IterT;
 
@@ -90,7 +90,7 @@ public:
 
   /// Converts any language locale from UI to internal integer code
   static int8_t MapLocaleToInteger(string const & locale);
-  static int8_t const UNSUPPORTED_LOCALE_CODE = -1;
+  static constexpr int8_t kUnsupportedLocaleCode = -1;
 
 private:
   void AddCategory(Category & cat, vector<uint32_t> & types);
diff --git a/search/search_engine.cpp b/search/search_engine.cpp
index 7267125a40..2f36a6d8a6 100644
--- a/search/search_engine.cpp
+++ b/search/search_engine.cpp
@@ -40,7 +40,7 @@ class InitSuggestions
 public:
   void operator()(CategoriesHolder::Category::Name const & name)
   {
-    if (name.m_prefixLengthToSuggest != CategoriesHolder::Category::EMPTY_PREFIX_LENGTH)
+    if (name.m_prefixLengthToSuggest != CategoriesHolder::Category::kEmptyPrefixLength)
     {
       strings::UniString const uniName = NormalizeAndSimplifyString(name.m_name);