diff --git a/src/buffer_utils.cc b/src/buffer_utils.cc
index eadf6415..1d7e7d25 100644
--- a/src/buffer_utils.cc
+++ b/src/buffer_utils.cc
@@ -3,6 +3,7 @@
 #include "buffer_manager.hh"
 #include "event_manager.hh"
 
+#include <unistd.h>
 #include <sys/select.h>
 
 namespace Kakoune
diff --git a/src/color.cc b/src/color.cc
index 2dc71af0..d056fb25 100644
--- a/src/color.cc
+++ b/src/color.cc
@@ -1,6 +1,7 @@
 #include "color.hh"
 
 #include "exception.hh"
+#include "regex.hh"
 
 namespace Kakoune
 {
@@ -31,7 +32,7 @@ Color str_to_color(StringView color)
     if (color == "white")   return Colors::White;
 
     static const Regex rgb_regex{"rgb:[0-9a-fA-F]{6}"};
-    if (boost::regex_match(color.begin(), color.end(), rgb_regex))
+    if (regex_match(color.begin(), color.end(), rgb_regex))
     {
         unsigned l;
         sscanf(color.zstr() + 4, "%x", &l);
diff --git a/src/command_manager.cc b/src/command_manager.cc
index 96f4cb09..71131048 100644
--- a/src/command_manager.cc
+++ b/src/command_manager.cc
@@ -263,7 +263,7 @@ TokenList parse(StringView line)
                 String token = line.substr(token_start, pos - token_start);
                 static const Regex regex{R"(\\([ \t;\n]))"};
                 result.emplace_back(Token::Type::Raw, token_start, pos,
-                                    boost::regex_replace(token, regex, "\\1"));
+                                    regex_replace(token, regex, "\\1"));
             }
         }
 
diff --git a/src/commands.cc b/src/commands.cc
index 591f4622..1f8a72c5 100644
--- a/src/commands.cc
+++ b/src/commands.cc
@@ -27,6 +27,7 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
+#include <unistd.h>
 
 namespace Kakoune
 {
@@ -549,7 +550,7 @@ const CommandDesc add_hook_cmd = {
             if (context.are_user_hooks_disabled())
                 return;
 
-            if (boost::regex_match(param.begin(), param.end(), regex))
+            if (regex_match(param.begin(), param.end(), regex))
                 CommandManager::instance().execute(command, context, {},
                                                    { { "hook_param", param } });
         };
diff --git a/src/env_vars.cc b/src/env_vars.cc
index afee98aa..7a759399 100644
--- a/src/env_vars.cc
+++ b/src/env_vars.cc
@@ -1,8 +1,6 @@
 #include "env_vars.hh"
 
-#if __APPLE__
 extern char **environ;
-#endif
 
 namespace Kakoune
 {
diff --git a/src/file.cc b/src/file.cc
index b7697dab..66064bbf 100644
--- a/src/file.cc
+++ b/src/file.cc
@@ -7,6 +7,7 @@
 #include "completion.hh"
 #include "debug.hh"
 #include "unicode.hh"
+#include "regex.hh"
 
 #include <errno.h>
 #include <sys/types.h>
@@ -300,12 +301,12 @@ std::vector<String> complete_filename(StringView prefix,
     }
 
     const bool check_ignored_regex = not ignored_regex.empty() and
-        not boost::regex_match(fileprefix.c_str(), ignored_regex);
+        not regex_match(fileprefix.c_str(), ignored_regex);
 
     auto filter = [&](const dirent& entry)
     {
         return not check_ignored_regex or
-               not boost::regex_match(entry.d_name, ignored_regex);
+               not regex_match(entry.d_name, ignored_regex);
     };
     std::vector<String> res = list_files(fileprefix, dirname, filter);
     for (auto& file : res)
diff --git a/src/file.hh b/src/file.hh
index e1561ca9..3fe4bee9 100644
--- a/src/file.hh
+++ b/src/file.hh
@@ -1,8 +1,9 @@
 #ifndef file_hh_INCLUDED
 #define file_hh_INCLUDED
 
-#include "string.hh"
 #include "exception.hh"
+#include "string.hh"
+#include "regex.hh"
 
 namespace Kakoune
 {
diff --git a/src/highlighters.cc b/src/highlighters.cc
index a42b6c94..d9942b85 100644
--- a/src/highlighters.cc
+++ b/src/highlighters.cc
@@ -22,8 +22,6 @@ namespace Kakoune
 
 using namespace std::placeholders;
 
-using RegexIterator = boost::regex_iterator<BufferIterator>;
-
 template<typename T>
 void highlight_range(DisplayBuffer& display_buffer,
                      ByteCoord begin, ByteCoord end,
@@ -256,9 +254,11 @@ private:
         cache.m_timestamp = buffer.timestamp();
 
         cache.m_matches.clear();
-        RegexIterator re_it{buffer.iterator_at(cache.m_range.first),
-                            buffer.iterator_at(cache.m_range.second+1), m_regex};
-        RegexIterator re_end;
+
+        using RegexIt = RegexIterator<BufferIterator>;
+        RegexIt re_it{buffer.iterator_at(cache.m_range.first),
+                      buffer.iterator_at(cache.m_range.second+1), m_regex};
+        RegexIt re_end;
         for (; re_it != re_end; ++re_it)
         {
             cache.m_matches.emplace_back();
@@ -281,8 +281,8 @@ HighlighterAndId highlight_regex_factory(HighlighterParameters params)
         FacesSpec faces;
         for (auto it = params.begin() + 1;  it != params.end(); ++it)
         {
-            boost::smatch res;
-            if (not boost::regex_match(it->begin(), it->end(), res, face_spec_ex))
+            MatchResults<String::const_iterator> res;
+            if (not regex_match(it->begin(), it->end(), res, face_spec_ex))
                 throw runtime_error("wrong face spec: '" + *it +
                                      "' expected <capture>:<facespec>");
             get_face(res[2].str()); // throw if wrong face spec
@@ -299,7 +299,7 @@ HighlighterAndId highlight_regex_factory(HighlighterParameters params)
         return HighlighterAndId(id, RegexHighlighter(std::move(ex),
                                                    std::move(faces)));
     }
-    catch (boost::regex_error& err)
+    catch (RegexError& err)
     {
         throw runtime_error(String("regex error: ") + err.what());
     }
@@ -364,7 +364,7 @@ HighlighterAndId highlight_search_factory(HighlighterParameters params)
             {
                 return s.empty() ? Regex{} : Regex{s.begin(), s.end()};
             }
-            catch (boost::regex_error& err)
+            catch (RegexError& err)
             {
                 return Regex{};
             }
@@ -725,7 +725,7 @@ void find_matches(const Buffer& buffer, RegexMatchList& matches, const Regex& re
     for (auto line = 0_line, end = buffer.line_count(); line < end; ++line)
     {
         auto l = buffer[line];
-        for (boost::regex_iterator<const char*> it{l.begin(), l.end(), regex}, end{}; it != end; ++it)
+        for (RegexIterator<const char*> it{l.begin(), l.end(), regex}, end{}; it != end; ++it)
         {
             ByteCount b = (int)((*it)[0].first - l.begin());
             ByteCount e = (int)((*it)[0].second - l.begin());
@@ -779,7 +779,7 @@ void update_matches(const Buffer& buffer, memoryview<LineModification> modifs,
              line < buffer.line_count(); ++line)
         {
             auto l = buffer[line];
-            for (boost::regex_iterator<const char*> it{l.begin(), l.end(), regex}, end{}; it != end; ++it)
+            for (RegexIterator<const char*> it{l.begin(), l.end(), regex}, end{}; it != end; ++it)
             {
                 ByteCount b = (int)((*it)[0].first - l.begin());
                 ByteCount e = (int)((*it)[0].second - l.begin());
@@ -1069,7 +1069,7 @@ HighlighterAndId regions_factory(HighlighterParameters params)
                 HierachicalHighlighter(
                     RegionsHighlighter(std::move(regions), std::move(default_group)), std::move(groups))};
     }
-    catch (boost::regex_error& err)
+    catch (RegexError& err)
     {
         throw runtime_error(String("regex error: ") + err.what());
     }
diff --git a/src/hook_manager.cc b/src/hook_manager.cc
index 7d804696..cfade4d7 100644
--- a/src/hook_manager.cc
+++ b/src/hook_manager.cc
@@ -2,6 +2,7 @@
 
 #include "context.hh"
 #include "debug.hh"
+#include "regex.hh"
 
 namespace Kakoune
 {
@@ -50,7 +51,7 @@ void HookManager::run_hook(const String& hook_name,
     for (auto& hook : hook_list_it->second)
     {
         if (not hook.first.empty() and not disabled_hooks.empty() and
-            boost::regex_match(hook.first, disabled_hooks))
+            regex_match(hook.first, disabled_hooks))
             continue;
 
         try
diff --git a/src/input_handler.cc b/src/input_handler.cc
index d8c1e373..e4368e7f 100644
--- a/src/input_handler.cc
+++ b/src/input_handler.cc
@@ -7,6 +7,7 @@
 #include "face_registry.hh"
 #include "insert_completer.hh"
 #include "normal.hh"
+#include "regex.hh"
 #include "register_manager.hh"
 #include "user_interface.hh"
 #include "utf8.hh"
@@ -338,7 +339,7 @@ public:
     void on_key(Key key) override
     {
         auto match_filter = [this](const String& str) {
-            return boost::regex_match(str.begin(), str.end(), m_filter);
+            return regex_match(str.begin(), str.end(), m_filter);
         };
 
         if (key == ctrl('m'))
@@ -356,7 +357,7 @@ public:
             if (m_edit_filter)
             {
                 m_edit_filter = false;
-                m_filter = boost::regex(".*");
+                m_filter = Regex(".*");
                 m_filter_editor.reset("");
                 context().print_status(DisplayLine{});
             }
@@ -395,7 +396,7 @@ public:
             m_filter_editor.handle_key(key);
 
             auto search = ".*" + m_filter_editor.line() + ".*";
-            m_filter = boost::regex(search.begin(), search.end());
+            m_filter = Regex(search.begin(), search.end());
             auto it = std::find_if(m_selected, m_choices.end(), match_filter);
             if (it == m_choices.end())
                 it = std::find_if(m_choices.begin(), m_selected, match_filter);
@@ -435,9 +436,9 @@ private:
         m_callback(selected, MenuEvent::Select, context());
     }
 
-    boost::regex m_filter = boost::regex(".*");
-    bool         m_edit_filter = false;
-    LineEditor   m_filter_editor;
+    Regex      m_filter = Regex(".*");
+    bool       m_edit_filter = false;
+    LineEditor m_filter_editor;
 };
 
 String common_prefix(memoryview<String> strings)
diff --git a/src/insert_completer.cc b/src/insert_completer.cc
index 1e50d189..da374d27 100644
--- a/src/insert_completer.cc
+++ b/src/insert_completer.cc
@@ -7,6 +7,7 @@
 #include "display_buffer.hh"
 #include "face_registry.hh"
 #include "file.hh"
+#include "regex.hh"
 #include "user_interface.hh"
 #include "window.hh"
 #include "word_db.hh"
@@ -162,14 +163,14 @@ InsertCompletion complete_filename(const Buffer& buffer, ByteCoord cursor_pos,
 InsertCompletion complete_option(const Buffer& buffer, ByteCoord cursor_pos,
                                  OptionManager& options, StringView option_name)
 {
-    const StringList& opt = options[option_name].get<StringList>();;
+    const StringList& opt = options[option_name].get<StringList>();
     if (opt.empty())
         return {};
 
     auto& desc = opt[0];
     static const Regex re(R"((\d+)\.(\d+)(?:\+(\d+))?@(\d+))");
-    boost::smatch match;
-    if (boost::regex_match(desc.begin(), desc.end(), match, re))
+    MatchResults<String::const_iterator> match;
+    if (regex_match(desc.begin(), desc.end(), match, re))
     {
         ByteCoord coord{ str_to_int(match[1].str()) - 1, str_to_int(match[2].str()) - 1 };
         if (not buffer.is_valid(coord))
diff --git a/src/ncurses.cc b/src/ncurses.cc
index 15d38d46..ef1bba40 100644
--- a/src/ncurses.cc
+++ b/src/ncurses.cc
@@ -16,10 +16,11 @@
 #include <ncursesw/ncurses.h>
 #endif
 
-#include <signal.h>
-#include <termios.h>
-#include <sys/ioctl.h>
 #include <fcntl.h>
+#include <signal.h>
+#include <sys/ioctl.h>
+#include <termios.h>
+#include <unistd.h>
 
 namespace Kakoune
 {
diff --git a/src/normal.cc b/src/normal.cc
index fbd23ae8..a5f75269 100644
--- a/src/normal.cc
+++ b/src/normal.cc
@@ -546,7 +546,7 @@ void regex_prompt(Context& context, const String prompt, T func)
                     context.push_jump();
                 func(str.empty() ? Regex{} : Regex{str}, event, context);
             }
-            catch (boost::regex_error& err)
+            catch (RegexError& err)
             {
                 if (event == PromptEvent::Validate)
                     throw runtime_error("regex error: "_str + err.what());
@@ -607,7 +607,7 @@ void search_next(Context& context, int param)
                 select_next_match<direction, mode>(context.buffer(), context.selections(), ex);
             } while (--param > 0);
         }
-        catch (boost::regex_error& err)
+        catch (RegexError& err)
         {
             throw runtime_error("regex error: "_str + err.what());
         }
@@ -732,8 +732,8 @@ void keep(Context& context, int)
         std::vector<Selection> keep;
         for (auto& sel : context.selections())
         {
-            if (boost::regex_search(buffer.iterator_at(sel.min()),
-                                    utf8::next(buffer.iterator_at(sel.max()), buffer.end()), ex) == matching)
+            if (regex_search(buffer.iterator_at(sel.min()),
+                             utf8::next(buffer.iterator_at(sel.max()), buffer.end()), ex) == matching)
                 keep.push_back(sel);
         }
         if (keep.empty())
diff --git a/src/option_manager.hh b/src/option_manager.hh
index 93e6a943..32d55e70 100644
--- a/src/option_manager.hh
+++ b/src/option_manager.hh
@@ -5,6 +5,7 @@
 #include "exception.hh"
 #include "option_types.hh"
 #include "utils.hh"
+#include "regex.hh"
 
 #include <unordered_map>
 
diff --git a/src/regex.cc b/src/regex.cc
new file mode 100644
index 00000000..d2c8f615
--- /dev/null
+++ b/src/regex.cc
@@ -0,0 +1,25 @@
+#include "regex.hh"
+
+#include "exception.hh"
+
+namespace Kakoune
+{
+
+String option_to_string(const Regex& re)
+{
+    return String{re.str()};
+}
+
+void option_from_string(StringView str, Regex& re)
+{
+    try
+    {
+        re = Regex{str.begin(), str.end()};
+    }
+    catch (RegexError& err)
+    {
+        throw runtime_error("unable to create regex: "_str + err.what());
+    }
+}
+
+}
diff --git a/src/regex.hh b/src/regex.hh
new file mode 100644
index 00000000..a3e911bd
--- /dev/null
+++ b/src/regex.hh
@@ -0,0 +1,33 @@
+#ifndef regex_hh_INCLUDED
+#define regex_hh_INCLUDED
+
+#include "string.hh"
+
+#if 0
+#include <regex>
+namespace kak_regex_ns = std;
+#else
+#include <boost/regex.hpp>
+namespace kak_regex_ns = boost;
+#endif
+
+namespace Kakoune
+{
+
+using Regex = kak_regex_ns::regex;
+
+template<typename Iterator>
+using RegexIterator = kak_regex_ns::regex_iterator<Iterator>;
+
+template<typename Iterator>
+using MatchResults = kak_regex_ns::match_results<Iterator>;
+
+using RegexError = kak_regex_ns::regex_error;
+
+String option_to_string(const Regex& re);
+void option_from_string(StringView str, Regex& re);
+
+}
+
+#endif // regex_hh_INCLUDED
+
diff --git a/src/selectors.cc b/src/selectors.cc
index f4569600..d6c9110a 100644
--- a/src/selectors.cc
+++ b/src/selectors.cc
@@ -496,6 +496,8 @@ void select_buffer(SelectionList& selections)
     selections = SelectionList{ buffer, target_eol({{0,0}, buffer.back_coord()}) };
 }
 
+using RegexIt = RegexIterator<BufferIterator>;
+
 void select_all_matches(SelectionList& selections, const Regex& regex)
 {
     std::vector<Selection> result;
@@ -503,8 +505,8 @@ void select_all_matches(SelectionList& selections, const Regex& regex)
     for (auto& sel : selections)
     {
         auto sel_end = utf8::next(buffer.iterator_at(sel.max()), buffer.end());
-        RegexIterator re_it(buffer.iterator_at(sel.min()), sel_end, regex);
-        RegexIterator re_end;
+        RegexIt re_it(buffer.iterator_at(sel.min()), sel_end, regex);
+        RegexIt re_end;
 
         for (; re_it != re_end; ++re_it)
         {
@@ -537,9 +539,8 @@ void split_selections(SelectionList& selections, const Regex& regex)
     {
         auto begin = buffer.iterator_at(sel.min());
         auto sel_end = utf8::next(buffer.iterator_at(sel.max()), buffer.end());
-        RegexIterator re_it(begin, sel_end, regex,
-                            boost::regex_constants::match_nosubs);
-        RegexIterator re_end;
+        RegexIt re_it(begin, sel_end, regex);
+        RegexIt re_end;
 
         for (; re_it != re_end; ++re_it)
         {
diff --git a/src/selectors.hh b/src/selectors.hh
index 1cd17b0a..3df24f26 100644
--- a/src/selectors.hh
+++ b/src/selectors.hh
@@ -5,6 +5,7 @@
 #include "buffer_utils.hh"
 #include "unicode.hh"
 #include "utf8_iterator.hh"
+#include "regex.hh"
 
 namespace Kakoune
 {
@@ -59,8 +60,6 @@ inline Selection utf8_range(const Utf8Iterator& first, const Utf8Iterator& last)
     return {first.base().coord(), last.base().coord()};
 }
 
-using RegexIterator = boost::regex_iterator<BufferIterator>;
-
 template<WordType word_type>
 Selection select_to_next_word(const Buffer& buffer, const Selection& selection)
 {
@@ -230,13 +229,12 @@ void select_buffer(SelectionList& selections);
 
 enum Direction { Forward, Backward };
 
-using MatchResults = boost::match_results<BufferIterator>;
-
 inline bool find_last_match(BufferIterator begin, const BufferIterator& end,
-                            MatchResults& res, const Regex& regex)
+                            MatchResults<BufferIterator>& res,
+                            const Regex& regex)
 {
-    MatchResults matches;
-    while (boost::regex_search(begin, end, matches, regex))
+    MatchResults<BufferIterator> matches;
+    while (regex_search(begin, end, matches, regex))
     {
         if (begin == matches[0].second)
             break;
@@ -248,11 +246,12 @@ inline bool find_last_match(BufferIterator begin, const BufferIterator& end,
 
 template<Direction direction>
 bool find_match_in_buffer(const Buffer& buffer, const BufferIterator pos,
-                          MatchResults& matches, const Regex& ex)
+                          MatchResults<BufferIterator>& matches,
+                          const Regex& ex)
 {
     if (direction == Forward)
-        return (boost::regex_search(pos, buffer.end(), matches, ex) or
-                boost::regex_search(buffer.begin(), buffer.end(), matches, ex));
+        return (regex_search(pos, buffer.end(), matches, ex) or
+                regex_search(buffer.begin(), buffer.end(), matches, ex));
     else
         return (find_last_match(buffer.begin(), pos, matches, ex) or
                 find_last_match(buffer.begin(), buffer.end(), matches, ex));
@@ -265,7 +264,7 @@ Selection find_next_match(const Buffer& buffer, const Selection& sel, const Rege
     auto end = begin;
 
     CaptureList captures;
-    MatchResults matches;
+    MatchResults<BufferIterator> matches;
     bool found = false;
     auto pos = direction == Forward ? utf8::next(begin, buffer.end())
                                     : utf8::previous(begin, buffer.begin());
diff --git a/src/shell_manager.cc b/src/shell_manager.cc
index 08c34160..e105f102 100644
--- a/src/shell_manager.cc
+++ b/src/shell_manager.cc
@@ -87,8 +87,8 @@ String ShellManager::pipe(StringView input,
         dup2(error_pipe[1], 2); close(error_pipe[1]);
         dup2(write_pipe[0], 0); close(write_pipe[0]);
 
-        boost::regex_iterator<StringView::iterator> it(cmdline.begin(), cmdline.end(), env_var_regex);
-        boost::regex_iterator<StringView::iterator> end;
+        RegexIterator<StringView::iterator> it(cmdline.begin(), cmdline.end(), env_var_regex);
+        RegexIterator<StringView::iterator> end;
 
         while (it != end)
         {
@@ -145,8 +145,7 @@ String ShellManager::get_val(StringView name, const Context& context) const
     auto env_var = std::find_if(
         m_env_vars.begin(), m_env_vars.end(),
         [&](const std::pair<Regex, EnvVarRetriever>& pair)
-        { return boost::regex_match(name.begin(), name.end(),
-                                    pair.first); });
+        { return regex_match(name.begin(), name.end(), pair.first); });
 
     if (env_var == m_env_vars.end())
         throw runtime_error("no such env var: " + name);
diff --git a/src/shell_manager.hh b/src/shell_manager.hh
index f5d27a03..e2af4241 100644
--- a/src/shell_manager.hh
+++ b/src/shell_manager.hh
@@ -2,6 +2,7 @@
 #define shell_manager_hh_INCLUDED
 
 #include "string.hh"
+#include "regex.hh"
 #include "utils.hh"
 #include "env_vars.hh"
 
diff --git a/src/string.cc b/src/string.cc
index 172193d4..f31ed83f 100644
--- a/src/string.cc
+++ b/src/string.cc
@@ -85,23 +85,6 @@ String to_string(int val)
     return buf;
 }
 
-String option_to_string(const Regex& re)
-{
-    return String{re.str()};
-}
-
-void option_from_string(StringView str, Regex& re)
-{
-    try
-    {
-        re = Regex{str.begin(), str.end()};
-    }
-    catch (boost::regex_error& err)
-    {
-        throw runtime_error("unable to create regex: "_str + err.what());
-    }
-}
-
 bool prefix_match(StringView str, StringView prefix)
 {
     auto it = str.begin();
diff --git a/src/string.hh b/src/string.hh
index 573853fe..e31a3173 100644
--- a/src/string.hh
+++ b/src/string.hh
@@ -6,13 +6,12 @@
 #include "utf8.hh"
 
 #include <string>
-#include <boost/regex.hpp>
+#include <climits>
+#include <cstring>
 
 namespace Kakoune
 {
 
-using Regex = boost::regex;
-
 class StringView;
 
 class String : public std::string
@@ -288,9 +287,6 @@ inline String codepoint_to_str(Codepoint cp)
     return String(str);
 }
 
-String option_to_string(const Regex& re);
-void option_from_string(StringView str, Regex& re);
-
 int str_to_int(StringView str);
 
 String to_string(int val);