diff --git a/CMakeLists.txt b/CMakeLists.txt
index e8361d968..752ebd31f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -324,9 +324,6 @@ set(memgraph_src_files
     ${src_dir}/config/config.cpp
     ${src_dir}/dbms/dbms.cpp
 #    ${src_dir}/dbms/cleaner.cpp
-    ${src_dir}/utils/string/transform.cpp
-    ${src_dir}/utils/string/join.cpp
-    ${src_dir}/utils/string/file.cpp
     ${src_dir}/utils/numerics/saturate.cpp
     ${src_dir}/io/network/addrinfo.cpp
     ${src_dir}/io/network/network_endpoint.cpp
diff --git a/src/copy_hardcoded_queries.cpp b/src/copy_hardcoded_queries.cpp
index bcfcb3abb..b840674b1 100644
--- a/src/copy_hardcoded_queries.cpp
+++ b/src/copy_hardcoded_queries.cpp
@@ -10,23 +10,31 @@ namespace fs = std::experimental::filesystem;
 #include "utils/command_line/arguments.hpp"
 #include "utils/exceptions/basic_exception.hpp"
 #include "utils/file.hpp"
-#include "utils/string/file.hpp"
-#include "utils/string/trim.hpp"
+#include "utils/string.hpp"
 
-std::string extract_query(const fs::path &path) {
+/**
+ * Reads a query from the file specified by the path argument.
+ * The first line of a query should start with "// Query: ". Query can be
+ * in more than one line but every line has to start with "//".
+ *
+ * @param path to the query file.
+ * @return query as a string.
+ */
+
+std::string ExtractQuery(const fs::path &path) {
   auto comment_mark = std::string("// ");
   auto query_mark = comment_mark + std::string("Query: ");
-  auto lines = utils::read_lines(path);
+  auto lines = utils::ReadLines(path);
   // find the line with a query (the query can be split across multiple
   // lines)
-  for (int i = 0; i < (int)lines.size(); ++i) {
+  for (int i = 0; i < static_cast<int>(lines.size()); ++i) {
     // find query in the line
     auto &line = lines[i];
     auto pos = line.find(query_mark);
     // if query doesn't exist pass
     if (pos == std::string::npos) continue;
-    auto query = utils::trim(line.substr(pos + query_mark.size()));
-    while (i + 1 < (int)lines.size() &&
+    auto query = utils::Trim(line.substr(pos + query_mark.size()));
+    while (i + 1 < static_cast<int>(lines.size()) &&
            lines[i + 1].find(comment_mark) != std::string::npos) {
       query += lines[i + 1].substr(lines[i + 1].find(comment_mark) +
                                    comment_mark.length());
@@ -61,7 +69,7 @@ int main(int argc, char **argv) {
 
   QueryPreprocessor preprocessor;
   for (auto &src_file : src_files) {
-    auto query = extract_query(src_file);
+    auto query = ExtractQuery(src_file);
     auto query_hash = preprocessor.preprocess(query).hash;
     auto dst_file = dst_path / fs::path(std::to_string(query_hash) + ".cpp");
     fs::copy(src_file, dst_file, fs::copy_options::overwrite_existing);
diff --git a/src/query/engine.hpp b/src/query/engine.hpp
index 00f5093f5..5f9eb16f0 100644
--- a/src/query/engine.hpp
+++ b/src/query/engine.hpp
@@ -9,10 +9,10 @@ namespace fs = std::experimental::filesystem;
 #include "logging/loggable.hpp"
 #include "query/exceptions.hpp"
 #include "query/frontend/opencypher/parser.hpp"
+#include "query/interpreter.hpp"
 #include "query/plan_compiler.hpp"
 #include "query/plan_interface.hpp"
 #include "query/preprocessor.hpp"
-#include "query/interpreter.hpp"
 #include "utils/dynamic_lib.hpp"
 
 /**
@@ -26,11 +26,12 @@ namespace fs = std::experimental::filesystem;
  *         the results should be returned (more optimal then just return
  *         the whole result set)
  */
-template <typename Stream> class QueryEngine : public Loggable {
-private:
+template <typename Stream>
+class QueryEngine : public Loggable {
+ private:
   using QueryPlanLib = DynamicLib<QueryPlanTrait<Stream>>;
 
-public:
+ public:
   QueryEngine() : Loggable("QueryEngine") {}
 
   /**
@@ -63,7 +64,6 @@ public:
    */
   auto Run(const std::string &query, GraphDbAccessor &db_accessor,
            Stream &stream) {
-
     if (CONFIG_BOOL(config::INTERPRET)) {
       query::Interpret(query, db_accessor, stream);
       return true;
@@ -109,12 +109,12 @@ public:
    *
    * @return size_t the number of loaded query plans
    */
-  auto Size() { // TODO: const once whan ConcurrentMap::Accessor becomes const
+  auto Size() {  // TODO: const once whan ConcurrentMap::Accessor becomes const
     return query_plans.access().size();
   }
   // return query_plans.access().size(); }
 
-private:
+ private:
   /**
    * Loads query plan eather from hardcoded folder or from the file that is
    * generated in this method.
@@ -175,13 +175,13 @@ private:
     auto path_so = CONFIG(config::COMPILE_PATH) + std::to_string(hash) + "_" +
                    (std::string)Timestamp::now() + ".so";
 
-    plan_compiler.compile(path_cpp, path_so);
+    plan_compiler.Compile(path_cpp, path_so);
 
     auto query_plan = std::make_unique<QueryPlanLib>(path_so);
     // TODO: underlying object has to be live during query execution
     //       fix that when Antler will be introduced into the database
 
-    auto query_plan_instance = query_plan->instance(); // because of move
+    auto query_plan_instance = query_plan->instance();  // because of move
     plans_accessor.insert(hash, std::move(query_plan));
 
     // return an instance of runnable code (PlanInterface)
diff --git a/src/query/plan_compiler.hpp b/src/query/plan_compiler.hpp
index a5594267c..a4c866e79 100644
--- a/src/query/plan_compiler.hpp
+++ b/src/query/plan_compiler.hpp
@@ -6,7 +6,7 @@
 #include "logging/loggable.hpp"
 #include "query/exceptions.hpp"
 #include "query/plan_compiler_flags.hpp"
-#include "utils/string/join.hpp"
+#include "utils/string.hpp"
 
 // TODO:
 //     * all libraries have to be compiled in the server compile time
@@ -27,19 +27,18 @@ class PlanCompiler : public Loggable {
    *
    * @return void
    */
-  void compile(const std::string &in_file, const std::string &out_file) {
+  void Compile(const std::string &in_file, const std::string &out_file) {
     // generate compile command
-    auto compile_command = utils::prints(
-        "clang++", compile_flags,
+    auto compile_command =
+        utils::Join({"clang++", compile_flags,
 #ifdef HARDCODED_OUTPUT_STREAM
-        "-DHARDCODED_OUTPUT_STREAM",
+                     "-DHARDCODED_OUTPUT_STREAM",
 #endif
-        in_file,         // input file
-        "-o", out_file,  // ouput file
-        include_dirs,
-        link_dirs, "-lmemgraph_pic",
-        "-shared -fPIC"  // shared library flags
-        );
+                     in_file,         // input file
+                     "-o", out_file,  // ouput file
+                     include_dirs, link_dirs, "-lmemgraph_pic",
+                     "-shared -fPIC"},  // shared library flags
+                    " ");
 
     logger.debug("compile command -> {}", compile_command);
 
diff --git a/src/template_engine/engine.cpp b/src/template_engine/engine.cpp
index 2ff68a701..35ce1fe5b 100644
--- a/src/template_engine/engine.cpp
+++ b/src/template_engine/engine.cpp
@@ -1,17 +1,25 @@
 #include "template_engine/engine.hpp"
 
-#include "utils/string/replace.hpp"
+#include "utils/string.hpp"
 
 namespace template_engine {
 
-string render(const string& form, const data& partials) {
+/**
+ * Replaces all placeholders in the form string marked as {{ key }} with values
+ * defined in the partials dictionary.
+ *
+ * @param form template string.
+ * @param partials values to inject into the template string.
+ * @return string rendered based on template string and values.
+ */
+std::string Render(const std::string &form, const data &partials) {
   //  TODO more optimal implementation
   //  another option is something like https://github.com/no1msd/mstch
   //  but it has to be wrapped
   string rendered = form;
-  for (auto partial : partials) {
+  for (const auto &partial : partials) {
     string key = "{{" + partial.first + "}}";
-    rendered = utils::replace(rendered, key, partial.second);
+    rendered = utils::Replace(rendered, key, partial.second);
   }
   return rendered;
 }
diff --git a/src/template_engine/engine.hpp b/src/template_engine/engine.hpp
index 8bcae45b1..64506147b 100644
--- a/src/template_engine/engine.hpp
+++ b/src/template_engine/engine.hpp
@@ -6,7 +6,7 @@
 namespace template_engine {
 
 using std::string;
-using data = std::unordered_map<string, string>;
+using data = std::unordered_map<std::string, std::string>;
 
-string render(const string& form, const data& partials);
+std::string Render(const string& form, const data& partials);
 }
diff --git a/src/utils/file.hpp b/src/utils/file.hpp
index 4fbd85287..cf3c3aafe 100644
--- a/src/utils/file.hpp
+++ b/src/utils/file.hpp
@@ -1,7 +1,7 @@
 #pragma once
 
-#include <fstream>
 #include <experimental/filesystem>
+#include <fstream>
 namespace fs = std::experimental::filesystem;
 
 namespace utils {
@@ -50,4 +50,36 @@ inline auto LoadFilePaths(const fs::path &directory,
 
   return file_paths;
 }
+
+// TODO: add error checking
+/**
+ * Reads all lines from the file specified by path.
+ *
+ * @param path file path.
+ * @return vector of all lines from the file.
+ */
+std::vector<std::string> ReadLines(const fs::path &path) {
+  std::vector<std::string> lines;
+
+  std::ifstream stream(path.c_str());
+  std::string line;
+  while (std::getline(stream, line)) {
+    lines.emplace_back(line);
+  }
+
+  return lines;
+}
+
+/**
+ * Writes test into the file specified by path.
+ *
+ * @param text content which will be written in the file.
+ * @param path a path to the file.
+ */
+void Write(const std::string &text, const fs::path &path) {
+  std::ofstream stream;
+  stream.open(path.c_str());
+  stream << text;
+  stream.close();
+}
 }
diff --git a/src/utils/fswatcher.hpp b/src/utils/fswatcher.hpp
index 0f0639477..14b4c656f 100644
--- a/src/utils/fswatcher.hpp
+++ b/src/utils/fswatcher.hpp
@@ -12,7 +12,6 @@
 #include <limits.h>
 #include <sys/inotify.h>
 #include <unistd.h>
-#include <unistd.h>
 #include <atomic>
 #include <chrono>
 #include <mutex>
diff --git a/src/utils/string.hpp b/src/utils/string.hpp
new file mode 100644
index 000000000..a92c7c41b
--- /dev/null
+++ b/src/utils/string.hpp
@@ -0,0 +1,95 @@
+#pragma once
+
+#include <algorithm>
+#include <cctype>
+#include <string>
+
+#include <iterator>
+#include <sstream>
+#include <string>
+#include <vector>
+
+namespace utils {
+
+/**
+ * Removes whitespace characters from the start and from the end of a string.
+ *
+ * @param str string that is going to be trimmed
+ *
+ * @return trimmed string
+ */
+std::string Trim(const std::string& s) {
+  auto begin = s.begin();
+  auto end = s.end();
+  if (begin == end) {
+    // Need to check this to be sure that prev(end) exists.
+    return s;
+  }
+  while (begin != end && isspace(*begin)) {
+    ++begin;
+  }
+  while (prev(end) != begin && isspace(*prev(end))) {
+    --end;
+  }
+  return std::string(begin, end);
+}
+
+/**
+ * Return string with all lowercased characters (locale independent).
+ */
+std::string ToLowerCase(std::string s) {
+  std::transform(s.begin(), s.end(), s.begin(),
+                 [](char c) { return tolower(c); });
+  return s;
+}
+
+/**
+ * Return string with all uppercased characters (locale independent).
+ */
+std::string ToUpperCase(std::string s) {
+  std::string s2(s.size(), ' ');
+  std::transform(s.begin(), s.end(), s.begin(),
+                 [](char c) { return toupper(c); });
+  return s;
+}
+
+/**
+ * Join strings in vector separated by a given separator.
+ */
+std::string Join(const std::vector<std::string>& strings,
+                 const char* separator) {
+  std::ostringstream oss;
+  std::copy(strings.begin(), strings.end(),
+            std::ostream_iterator<std::string>(oss, separator));
+  return oss.str();
+}
+
+/**
+ * Replaces all occurences of <match> in <src> with <replacement>.
+ */
+// TODO: This could be implemented much more efficient.
+std::string Replace(std::string src, const std::string& match,
+                    const std::string& replacement) {
+  for (size_t pos = src.find(match); pos != std::string::npos;
+       pos = src.find(match, pos + replacement.size())) {
+    src.erase(pos, match.length()).insert(pos, replacement);
+  }
+  return src;
+}
+
+/**
+ * Split string by delimeter and return vector of results.
+ */
+std::vector<std::string> Split(const std::string& src,
+                               const std::string& delimiter) {
+  size_t index = 0;
+  std::vector<std::string> res;
+  size_t n = src.find(delimiter, index);
+  while (n != std::string::npos) {
+    n = src.find(delimiter, index);
+    res.push_back(src.substr(index, n - index));
+    index = n + delimiter.size();
+  }
+  return res;
+}
+}
diff --git a/src/utils/string/all.hpp b/src/utils/string/all.hpp
deleted file mode 100644
index 24cee618f..000000000
--- a/src/utils/string/all.hpp
+++ /dev/null
@@ -1,6 +0,0 @@
-#pragma once
-
-#include "intercalate.hpp"
-#include "linereader.hpp"
-#include "replace.hpp"
-#include "split.hpp"
diff --git a/src/utils/string/file.cpp b/src/utils/string/file.cpp
deleted file mode 100644
index 711a7ce34..000000000
--- a/src/utils/string/file.cpp
+++ /dev/null
@@ -1,38 +0,0 @@
-#include "utils/string/file.hpp"
-
-#include <iterator>
-
-namespace utils {
-
-namespace fs = std::experimental::filesystem;
-
-Text read_text(const fs::path &path) {
-  std::ifstream in(path, std::ios::in | std::ios::binary);
-
-  if (in)
-    return Text(std::string(std::istreambuf_iterator<char>(in),
-                            std::istreambuf_iterator<char>()));
-
-  auto error_message = fmt::format("{0}{1}", "Fail to read: ", path.c_str());
-  throw std::runtime_error(error_message);
-}
-
-std::vector<std::string> read_lines(const fs::path &path) {
-  std::vector<std::string> lines;
-
-  std::ifstream stream(path.c_str());
-  std::string line;
-  while (std::getline(stream, line)) {
-    lines.emplace_back(line);
-  }
-
-  return lines;
-}
-
-void write(const Text &text, const fs::path &path) {
-  std::ofstream stream;
-  stream.open(path.c_str());
-  stream << text.str();
-  stream.close();
-}
-}
diff --git a/src/utils/string/file.hpp b/src/utils/string/file.hpp
deleted file mode 100644
index 3fd1ae509..000000000
--- a/src/utils/string/file.hpp
+++ /dev/null
@@ -1,61 +0,0 @@
-#pragma once
-
-#include <cerrno>
-#include <fstream>
-#include <ostream>
-#include <stdexcept>
-#include <streambuf>
-#include <string>
-
-#include <fmt/format.h>
-
-// TODO: remove experimental from here once that becomes possible
-#include <experimental/filesystem>
-namespace fs = std::experimental::filesystem;
-
-namespace utils {
-
-/*
- * Type safe text object.
- */
-class Text {
- public:
-  Text() = default;
-  explicit Text(const std::string& text) : text_(text) {}
-
-  // text could be huge and copy operationt would be too expensive
-  Text(const Text& other) = delete;
-  Text& operator=(const Text& other) = delete;
-
-  // the object is movable
-  Text(Text&& other) = default;
-  Text& operator=(Text&& other) {
-    text_ = std::move(other.text_);
-    return *this;
-  }
-
-  const std::string& str() const { return text_; }
-
- private:
-  std::string text_;
-};
-
-/*
- * Reads the whole text from a file at the path.
- */
-Text read_text(const fs::path& path);
-
-/*
- * Reads all the lines from a file at the path.
- */
-std::vector<std::string> read_lines(const fs::path& path);
-
-// TODO: lazy implementation of read_lines functionality (line by line)
-
-// TODO: read word by word + lazy implementation
-
-/*
- * Write text in a file at the path.
- */
-void write(const Text& text, const fs::path& path);
-}
diff --git a/src/utils/string/intercalate.hpp b/src/utils/string/intercalate.hpp
deleted file mode 100644
index c6c8aaa60..000000000
--- a/src/utils/string/intercalate.hpp
+++ /dev/null
@@ -1,23 +0,0 @@
-#pragma once
-
-#include <sstream>
-#include <string>
-
-namespace utils {
-
-template <typename It>
-std::string intercalate(It first, It last, const std::string& separator) {
-  if (first == last) return "";
-
-  std::stringstream ss;
-  It second(first);
-
-  // append the first N-1 elements with a separator
-  for (second++; second != last; ++first, ++second) ss << *first << separator;
-
-  // append the last element
-  ss << *first;
-
-  return ss.str();
-}
-}
diff --git a/src/utils/string/join.cpp b/src/utils/string/join.cpp
deleted file mode 100644
index dd7a746cb..000000000
--- a/src/utils/string/join.cpp
+++ /dev/null
@@ -1,12 +0,0 @@
-#include "utils/string/join.hpp"
-
-namespace utils {
-
-std::string join(const std::vector<std::string>& strings,
-                 const char* separator) {
-  std::ostringstream oss;
-  std::copy(strings.begin(), strings.end(),
-            std::ostream_iterator<std::string>(oss, separator));
-  return oss.str();
-}
-}
diff --git a/src/utils/string/join.hpp b/src/utils/string/join.hpp
deleted file mode 100644
index b61dd22aa..000000000
--- a/src/utils/string/join.hpp
+++ /dev/null
@@ -1,18 +0,0 @@
-#pragma once
-
-#include <iterator>
-#include <sstream>
-#include <string>
-#include <vector>
-
-namespace utils {
-
-std::string join(const std::vector<std::string>& strings,
-                 const char* separator);
-
-template <typename... Args>
-std::string prints(const Args&... args) {
-  std::vector<std::string> strings = {args...};
-  return join(strings, " ");
-}
-}
diff --git a/src/utils/string/linereader.hpp b/src/utils/string/linereader.hpp
deleted file mode 100644
index 226261420..000000000
--- a/src/utils/string/linereader.hpp
+++ /dev/null
@@ -1,27 +0,0 @@
-#pragma once
-
-#include <fstream>
-#include <functional>
-#include <string>
-
-namespace utils {
-
-void linereader(std::istream& stream,
-                std::function<void(const std::string&)> cb) {
-  std::string line;
-
-  while (std::getline(stream, line)) cb(line);
-}
-
-void linereader(const std::string& filename,
-                std::function<void(const std::string&)> cb) {
-  std::fstream fs(filename.c_str());
-
-  // should this throw an error? figure out how to handle this TODO
-
-  if (fs.is_open() == false)
-    throw std::runtime_error("[ERROR] can't open file " + filename);
-
-  linereader(fs, cb);
-}
-}
diff --git a/src/utils/string/replace.hpp b/src/utils/string/replace.hpp
deleted file mode 100644
index ed09a8b7a..000000000
--- a/src/utils/string/replace.hpp
+++ /dev/null
@@ -1,17 +0,0 @@
-#pragma once
-
-#include <string>
-
-namespace utils {
-
-// replaces all occurences of <match> in <src> with <replacement>
-
-std::string replace(std::string src, const std::string& match,
-                    const std::string& replacement) {
-  for (size_t pos = src.find(match); pos != std::string::npos;
-       pos = src.find(match, pos + replacement.size()))
-    src.erase(pos, match.length()).insert(pos, replacement);
-
-  return src;
-}
-}
diff --git a/src/utils/string/split.hpp b/src/utils/string/split.hpp
deleted file mode 100644
index 7851ed9ec..000000000
--- a/src/utils/string/split.hpp
+++ /dev/null
@@ -1,35 +0,0 @@
-#pragma once
-
-#include <regex>
-#include <vector>
-
-namespace utils {
-
-std::vector<std::string> split(const std::string& src,
-                               const std::string& delimiter) {
-  size_t index = 0;
-  std::vector<std::string> res;
-  size_t n = src.find(delimiter, index);
-
-  while (n != std::string::npos) {
-    n = src.find(delimiter, index);
-    res.push_back(src.substr(index, n - index));
-    index = n + delimiter.size();
-  }
-
-  return res;
-}
-
-// doesn't work with gcc even though it's only c++11...
-// and it's slow as hell compared to the split implementation above
-// (more powerful though)
-
-std::vector<std::string> regex_split(const std::string& input,
-                                     const std::string& regex) {
-  auto rgx = std::regex(regex);
-
-  std::sregex_token_iterator last, first{input.begin(), input.end(), rgx, -1};
-
-  return {first, last};
-}
-}
diff --git a/src/utils/string/streq.hpp b/src/utils/string/streq.hpp
deleted file mode 100644
index a86cfc421..000000000
--- a/src/utils/string/streq.hpp
+++ /dev/null
@@ -1,29 +0,0 @@
-#pragma once
-
-#include <x86intrin.h>
-
-namespace sse42 {
-constexpr int strcmp_mode = _SIDD_CMP_EQUAL_EACH | _SIDD_NEGATIVE_POLARITY;
-
-constexpr unsigned CF = 0x1;
-constexpr unsigned ZF = 0x40;
-
-bool streq(const char* lhs, const char* rhs) {
-  int idx, eflags;
-
-  while (true) {
-    auto lhs_mm = _mm_loadu_si128((__m128i*)lhs);
-    auto rhs_mm = _mm_loadu_si128((__m128i*)rhs);
-
-    idx = _mm_cmpistri(lhs_mm, rhs_mm, strcmp_mode);
-    eflags = __readeflags();
-
-    if (idx != 0x10) return false;
-
-    if ((eflags & (ZF | CF)) != 0) return true;
-
-    lhs += 16;
-    rhs += 16;
-  }
-}
-}
diff --git a/src/utils/string/transform.cpp b/src/utils/string/transform.cpp
deleted file mode 100644
index 1e043a5c9..000000000
--- a/src/utils/string/transform.cpp
+++ /dev/null
@@ -1,12 +0,0 @@
-#include "utils/string/transform.hpp"
-
-namespace utils {
-
-// TODO CPPCheck -> function never used
-void str_tolower(std::string& s) {
-  //  en_US.utf8 localization
-  std::transform(s.begin(), s.end(), s.begin(), [](unsigned char c) {
-    return std::tolower(c, std::locale("en_US.utf8"));
-  });
-}
-}
diff --git a/src/utils/string/transform.hpp b/src/utils/string/transform.hpp
deleted file mode 100644
index 21eea998e..000000000
--- a/src/utils/string/transform.hpp
+++ /dev/null
@@ -1,10 +0,0 @@
-#pragma once
-
-#include <algorithm>
-#include <locale>
-#include <string>
-
-namespace utils {
-
-void str_tolower(std::string& s);
-}
diff --git a/src/utils/string/trim.hpp b/src/utils/string/trim.hpp
deleted file mode 100644
index 09cb6d341..000000000
--- a/src/utils/string/trim.hpp
+++ /dev/null
@@ -1,22 +0,0 @@
-#pragma once
-
-#include <string>
-
-namespace utils {
-
-/**
- * Removes whitespace characters from the start and from the end of a string.
- *
- * @param str string that is going to be trimmed
- *
- * @return trimmed string
- */
-std::string trim(const std::string &str) {
-  size_t first = str.find_first_not_of(' ');
-  if (std::string::npos == first) {
-    return str;
-  }
-  size_t last = str.find_last_not_of(' ');
-  return str.substr(first, (last - first + 1));
-}
-}
diff --git a/src/utils/string/weak_string.hpp b/src/utils/string/weak_string.hpp
deleted file mode 100644
index 18eaa0d87..000000000
--- a/src/utils/string/weak_string.hpp
+++ /dev/null
@@ -1,62 +0,0 @@
-#pragma once
-
-#include <cstring>
-#include <string>
-
-#include "utils/assert.hpp"
-#include "utils/total_ordering.hpp"
-#include "utils/total_ordering_with.hpp"
-
-class WeakString {
- public:
-  constexpr WeakString() : str(nullptr), len(0) {}
-
-  WeakString(const std::string& str) : str(str.c_str()), len(str.size()) {}
-
-  WeakString(const char* str) : str(str), len(strlen(str)) {}
-
-  constexpr WeakString(const char* str, size_t len) : str(str), len(len) {}
-
-  const char& operator[](size_t idx) const {
-    debug_assert(idx < len, "Index not smaller than length.");
-    return str[idx];
-  }
-
-  const char& front() const {
-    debug_assert(len > 0, "String is empty.");
-    return str[0];
-  }
-
-  const char& back() const {
-    debug_assert(len > 0, "String is empty.");
-    return str[len - 1];
-  }
-
-  const char* data() const { return str; }
-
-  bool empty() const { return len == 0; }
-
-  size_t size() const { return len; }
-
-  size_t length() const { return size(); }
-
-  std::string to_string() const { return std::string(str, len); }
-
-  friend bool operator==(const WeakString& lhs, const WeakString rhs) {
-    // oh dear god, make this better with custom iterators
-    if (lhs.size() != rhs.size()) return false;
-
-    for (size_t i = 0; i < lhs.size(); ++i)
-      if (lhs[i] != rhs[i]) return false;
-
-    return true;
-  }
-
-  friend bool operator!=(const WeakString& lhs, const WeakString& rhs) {
-    return !(lhs == rhs);
-  }
-
- private:
-  const char* str;
-  size_t len;
-};
diff --git a/src/utils/variadic/variadic.hpp b/src/utils/variadic/variadic.hpp
deleted file mode 100644
index 3ece9803c..000000000
--- a/src/utils/variadic/variadic.hpp
+++ /dev/null
@@ -1,50 +0,0 @@
-#pragma once
-
-#include <iostream>
-
-namespace utils {
-
-/*
- * Variadic argument print
- */
-template <class Head>
-void print_vargs(std::ostream& s, Head&& head) {
-  s << std::forward<Head>(head);
-}
-template <class Head, class... Tail>
-void print_vargs(std::ostream& s, Head&& head, Tail&&... tail) {
-  s << std::forward<Head>(head);
-  print_vargs(s, std::forward<Tail>(tail)...);
-}
-
-/*
- * Compile time print line.
- *
- * USAGE:
- *     RUN: utils::printer("ONE ", "TWO");
- *     OUTPUT: "ONE TWO\n"
- *
- * TODO: reimplament with C++17 fold expressions
- */
-template <class... Args>
-void println(Args&&... args) {
-  print_vargs(std::cout, std::forward<Args>(args)...);
-  std::cout << std::endl;
-}
-
-// value equality with any of variadic argument
-// example: value == varg[0] OR value == varg[1] OR ...
-
-template <class Value, class Head>
-bool _or_vargs(Value&& value, Head&& head) {
-  return value == head;
-}
-template <class Value, class Head, class... Tail>
-bool _or_vargs(Value&& value, Head&& head, Tail&&... tail) {
-  return value == head || _or_vargs(std::forward<Value>(value), tail...);
-}
-template <class Value, class... Array>
-bool or_vargs(Value&& value, Array&&... array) {
-  return _or_vargs(std::forward<Value>(value), std::forward<Array>(array)...);
-}
-}
diff --git a/tests/integration/query_engine_common.hpp b/tests/integration/query_engine_common.hpp
index 755a797c8..99a52582a 100644
--- a/tests/integration/query_engine_common.hpp
+++ b/tests/integration/query_engine_common.hpp
@@ -12,8 +12,7 @@ namespace fs = std::experimental::filesystem;
 #include "stream/print_record_stream.hpp"
 #include "utils/command_line/arguments.hpp"
 #include "utils/file.hpp"
-#include "utils/string/file.hpp"
-#include "utils/string/trim.hpp"
+#include "utils/string.hpp"
 
 namespace tests {
 namespace integration {
@@ -55,7 +54,7 @@ auto LoadQueryHashes(Logger &log, const fs::path &path) {
   // hashes calculated from all queries in queries file
   QueryHashesT query_hashes;
   // fill the above set
-  auto queries = utils::read_lines(path);
+  auto queries = utils::ReadLines(path);
   for (auto &query : queries) {
     if (query.empty()) continue;
     query_hashes.insert(preprocessor.preprocess(query).hash);
@@ -86,7 +85,7 @@ auto LoadQueryPlans(Logger &log, QueryEngineT &engine,
   auto comment = std::string("// ");
   auto query_mark = comment + std::string("Query: ");
   for (auto &plan_path : plan_paths) {
-    auto lines = read_lines(plan_path);
+    auto lines = utils::ReadLines(plan_path);
     // find the line with a query in order
     // be able to place it in the dynamic libs container (base on query
     // hash)
@@ -96,7 +95,7 @@ auto LoadQueryPlans(Logger &log, QueryEngineT &engine,
       auto pos = line.find(query_mark);
       // if query doesn't exist pass
       if (pos == std::string::npos) continue;
-      auto query = trim(line.substr(pos + query_mark.size()));
+      auto query = utils::Trim(line.substr(pos + query_mark.size()));
       while (i + 1 < (int)lines.size() &&
              lines[i + 1].find(comment) != std::string::npos) {
         query +=
@@ -131,10 +130,10 @@ auto ExecuteQueryPlans(Logger &log, QueryEngineT &engine, Dbms &dbms,
                        const fs::path &path, StreamT &stream) {
   log.info("*** Execute the queries from the queries_file ***");
   // execute all queries from queries_file
-  auto queries = utils::read_lines(path);
+  auto queries = utils::ReadLines(path);
   for (auto &query : queries) {
     if (query.empty()) continue;
-    permanent_assert(engine.Loaded(trim(query)),
+    permanent_assert(engine.Loaded(utils::Trim(query)),
                      "Implementation wasn't loaded");
     // Create new db_accessor since one query is associated with one
     // transaction.
diff --git a/tests/manual/query_engine.cpp b/tests/manual/query_engine.cpp
index f7a233e6a..8823bf5bf 100644
--- a/tests/manual/query_engine.cpp
+++ b/tests/manual/query_engine.cpp
@@ -41,14 +41,14 @@ int main(int argc, char* argv[]) {
 
           auto comment = std::string("// ");
           auto query_mark = comment + std::string("Query: ");
-          auto lines = read_lines(event.path);
+          auto lines = utils::ReadLines(event.path);
           for (int i = 0; i < (int)lines.size(); ++i) {
             // find query in the line
             auto& line = lines[i];
             auto pos = line.find(query_mark);
             // if query doesn't exist pass
             if (pos == std::string::npos) continue;
-            auto query = trim(line.substr(pos + query_mark.size()));
+            auto query = utils::Trim(line.substr(pos + query_mark.size()));
             while (i + 1 < (int)lines.size() &&
                    lines[i + 1].find(comment) != std::string::npos) {
               query += lines[i + 1].substr(lines[i + 1].find(comment) +
diff --git a/tests/manual/query_hash.cpp b/tests/manual/query_hash.cpp
index 78715d8ed..ebb045f12 100644
--- a/tests/manual/query_hash.cpp
+++ b/tests/manual/query_hash.cpp
@@ -5,11 +5,7 @@
 #include "logging/streams/stdout.hpp"
 #include "query/preprocessor.hpp"
 #include "utils/command_line/arguments.hpp"
-#include "utils/string/file.hpp"
 #include "utils/type_discovery.hpp"
-#include "utils/variadic/variadic.hpp"
-
-using utils::println;
 
 /**
  * Useful when somebody wants to get a hash for some query.
@@ -32,13 +28,14 @@ int main(int argc, char **argv) {
   auto preprocessed = preprocessor.preprocess(query);
 
   // print query, stripped query, hash and variable values (propertie values)
-  println("Query: ", query);
-  println("Stripped query: ", preprocessed.query);
-  println("Query hash: ", preprocessed.hash);
-  println("Property values:");
-  for (int i = 0; i < preprocessed.arguments.Size(); ++i)
-    println("    ", preprocessed.arguments.At(i));
-  println("");
+  std::cout << fmt::format("Query: {}\n", query);
+  std::cout << fmt::format("Stripped query: {}\n", preprocessed.query);
+  std::cout << fmt::format("Query hash: {}\n", preprocessed.hash);
+  std::cout << fmt::format("Property values:\n");
+  for (int i = 0; i < static_cast<int>(preprocessed.arguments.Size()); ++i) {
+    fmt::format("    {}", preprocessed.arguments.At(i));
+  }
+  std::cout << std::endl;
 
   return 0;
 }
diff --git a/tests/unit/template_engine.cpp b/tests/unit/template_engine.cpp
index 25bbbe3d2..b54fe98e3 100644
--- a/tests/unit/template_engine.cpp
+++ b/tests/unit/template_engine.cpp
@@ -3,7 +3,7 @@
 #include "template_engine/engine.hpp"
 
 TEST(TemplateEngine, BasicPlaceholderReplacement) {
-  auto rendered = template_engine::render("{{one}} {{two}}",
+  auto rendered = template_engine::Render("{{one}} {{two}}",
                                           {{"one", "two"}, {"two", "one"}});
 
   ASSERT_EQ(rendered, "two one");