diff --git a/include/components/controller.hpp b/include/components/controller.hpp
index 7af3f14d..a1ae93af 100644
--- a/include/components/controller.hpp
+++ b/include/components/controller.hpp
@@ -7,6 +7,7 @@
 #include "events/signal_fwd.hpp"
 #include "events/signal_receiver.hpp"
 #include "events/types.hpp"
+#include "utils/file.hpp"
 #include "x11/types.hpp"
 #include "x11/events.hpp"
 
@@ -83,10 +84,7 @@ class controller : public signal_receiver<SIGN_PRIORITY_CONTROLLER, sig_ev::exit
   unique_ptr<inotify_watch> m_confwatch;
   unique_ptr<command> m_command;
 
-  unique_ptr<file_descriptor> m_fdevent_rd;
-  unique_ptr<file_descriptor> m_fdevent_wr;
-
-  thread m_event_thread;
+  array<unique_ptr<file_descriptor>, 2> m_queuefd{};
 
   /**
    * @brief Controls weather the output gets printed to stdout
@@ -133,6 +131,11 @@ class controller : public signal_receiver<SIGN_PRIORITY_CONTROLLER, sig_ev::exit
    * @brief Input data
    */
   string m_inputdata;
+
+  /**
+   * @brief Thread for the eventqueue loop
+   */
+  thread m_event_thread;
 };
 
 POLYBAR_NS_END
diff --git a/include/components/screen.hpp b/include/components/screen.hpp
index 9f06bcfd..47f76244 100644
--- a/include/components/screen.hpp
+++ b/include/components/screen.hpp
@@ -5,7 +5,7 @@
 #include "events/signal_emitter.hpp"
 #include "events/signal_fwd.hpp"
 #include "x11/events.hpp"
-#include "x11/extensions/fwd.hpp"
+#include "x11/extensions/randr.hpp"
 #include "x11/types.hpp"
 #include "x11/window.hpp"
 
diff --git a/include/components/types.hpp b/include/components/types.hpp
index b6ab18f1..e92adf54 100644
--- a/include/components/types.hpp
+++ b/include/components/types.hpp
@@ -1,13 +1,18 @@
 #pragma once
 
+#include <xcb/xcb.h>
+
 #include <string>
 #include <unordered_map>
 
 #include "common.hpp"
-#include "x11/extensions/randr.hpp"
 
 POLYBAR_NS
 
+// fwd
+struct randr_output;
+using monitor_t = shared_ptr<randr_output>;
+
 struct enum_hash {
   template <typename T>
   inline typename std::enable_if<std::is_enum<T>::value, size_t>::type operator()(T const value) const {
diff --git a/include/utils/color.hpp b/include/utils/color.hpp
index bb830d9b..ab826b22 100644
--- a/include/utils/color.hpp
+++ b/include/utils/color.hpp
@@ -74,8 +74,8 @@ namespace color_util {
   }
 
   inline string parse_hex(string hex) {
-    if (hex.substr(0, 1) != "#")
-      hex = "#" + hex;
+    if (hex[0] != '#')
+      hex.insert(0, 1, '#');
     if (hex.length() == 4)
       hex = {'#', hex[1], hex[1], hex[2], hex[2], hex[3], hex[3]};
     if (hex.length() == 7)
diff --git a/include/x11/color.hpp b/include/x11/color.hpp
index ed1c3f6a..40b9264c 100644
--- a/include/x11/color.hpp
+++ b/include/x11/color.hpp
@@ -3,9 +3,11 @@
 #include <map>
 
 #include <X11/Xft/Xft.h>
+#include <unordered_map>
 
 #include "common.hpp"
 #include "utils/color.hpp"
+#include "utils/concurrency.hpp"
 
 POLYBAR_NS
 
@@ -30,8 +32,10 @@ class color {
   string m_source;
 };
 
-extern color g_colorempty;
-extern color g_colorblack;
-extern color g_colorwhite;
+extern mutex_wrapper<std::unordered_map<string, color>> g_colorstore;
+
+extern const color& g_colorempty;
+extern const color& g_colorblack;
+extern const color& g_colorwhite;
 
 POLYBAR_NS_END
diff --git a/include/x11/connection.hpp b/include/x11/connection.hpp
index d08258a6..5db48292 100644
--- a/include/x11/connection.hpp
+++ b/include/x11/connection.hpp
@@ -6,7 +6,6 @@
 
 #include "common.hpp"
 #include "components/screen.hpp"
-#include "utils/file.hpp"
 #include "x11/events.hpp"
 #include "x11/extensions/all.hpp"
 #include "x11/registry.hpp"
diff --git a/src/components/controller.cpp b/src/components/controller.cpp
index 0c00419b..75e71306 100644
--- a/src/components/controller.cpp
+++ b/src/components/controller.cpp
@@ -25,7 +25,7 @@
 
 POLYBAR_NS
 
-int g_eventpipe[2]{0, 0};
+array<int, 2> g_eventpipe{{-1, -1}};
 sig_atomic_t g_reload{0};
 sig_atomic_t g_terminate{0};
 
@@ -61,13 +61,13 @@ controller::controller(connection& conn, signal_emitter& emitter, const logger&
   m_swallow_limit = m_conf.deprecated("settings", "eventqueue-swallow", "throttle-output", m_swallow_limit);
   m_swallow_update = m_conf.deprecated("settings", "eventqueue-swallow-time", "throttle-output-for", m_swallow_update);
 
-  if (pipe(g_eventpipe) != 0) {
+  if (pipe(g_eventpipe.data()) == 0) {
+    m_queuefd[PIPE_READ] = make_unique<file_descriptor>(g_eventpipe[PIPE_READ]);
+    m_queuefd[PIPE_WRITE] = make_unique<file_descriptor>(g_eventpipe[PIPE_WRITE]);
+  } else {
     throw system_error("Failed to create event channel pipes");
   }
 
-  m_fdevent_rd = file_util::make_file_descriptor(g_eventpipe[PIPE_READ]);
-  m_fdevent_wr = file_util::make_file_descriptor(g_eventpipe[PIPE_WRITE]);
-
   m_log.trace("controller: Install signal handler");
   struct sigaction act {};
   memset(&act, 0, sizeof(act));
@@ -234,13 +234,13 @@ bool controller::enqueue(string&& input_data) {
 void controller::read_events() {
   m_log.info("Entering event loop (thread-id=%lu)", this_thread::get_id());
 
-  int fd_connection{m_connection.get_file_descriptor()};
-  int fd_confwatch{0};
-  int fd_ipc{0};
+  int fd_connection{-1};
+  int fd_confwatch{-1};
+  int fd_ipc{-1};
 
   vector<int> fds;
-  fds.emplace_back(*m_fdevent_rd);
-  fds.emplace_back(fd_connection);
+  fds.emplace_back(*m_queuefd[PIPE_READ]);
+  fds.emplace_back(fd_connection = m_connection.get_file_descriptor());
 
   if (m_confwatch) {
     m_log.trace("controller: Attach config watch");
@@ -271,9 +271,9 @@ void controller::read_events() {
     }
 
     // Process event on the internal fd
-    if (m_fdevent_rd && FD_ISSET(*m_fdevent_rd, &readfds)) {
+    if (m_queuefd[PIPE_READ] && FD_ISSET(static_cast<int>(*m_queuefd[PIPE_READ]), &readfds)) {
       char buffer[BUFSIZ]{'\0'};
-      if (read(*m_fdevent_rd, &buffer, BUFSIZ) == -1) {
+      if (read(static_cast<int>(*m_queuefd[PIPE_READ]), &buffer, BUFSIZ) == -1) {
         m_log.err("Failed to read from eventpipe (err: %s)", strerror(errno));
       }
     }
@@ -454,6 +454,7 @@ bool controller::on(const sig_ev::update&) {
         block_contents += margin_left;
       }
 
+      block_contents.reserve(module_contents.size());
       block_contents += module_contents;
     }
 
diff --git a/src/modules/bspwm.cpp b/src/modules/bspwm.cpp
index 53aced5d..44ac5692 100644
--- a/src/modules/bspwm.cpp
+++ b/src/modules/bspwm.cpp
@@ -142,7 +142,6 @@ namespace modules {
       m_log.warn("%s: Reconnecting to socket...", name());
       m_subscriber = bspwm_util::make_subscriber();
     }
-
     return m_subscriber->peek(1);
   }
 
diff --git a/src/modules/meta/base.cpp b/src/modules/meta/base.cpp
index 46f4d335..967fcf42 100644
--- a/src/modules/meta/base.cpp
+++ b/src/modules/meta/base.cpp
@@ -78,7 +78,7 @@ namespace modules {
     format->bg = m_conf.get(m_modname, name + "-background", ""s);
     format->ul = m_conf.get(m_modname, name + "-underline", ""s);
     format->ol = m_conf.get(m_modname, name + "-overline", ""s);
-    format->spacing = m_conf.get(m_modname, name + "-spacing", 0_z);
+    format->spacing = m_conf.get(m_modname, name + "-spacing", 1_z);
     format->padding = m_conf.get(m_modname, name + "-padding", 0_z);
     format->margin = m_conf.get(m_modname, name + "-margin", 0_z);
     format->offset = m_conf.get(m_modname, name + "-offset", 0_z);
diff --git a/src/x11/color.cpp b/src/x11/color.cpp
index a9550ac9..38eb1571 100644
--- a/src/x11/color.cpp
+++ b/src/x11/color.cpp
@@ -1,5 +1,4 @@
 #include <iomanip>
-#include <unordered_map>
 #include <utility>
 
 #include "errors.hpp"
@@ -9,11 +8,11 @@
 
 POLYBAR_NS
 
-std::unordered_map<string, color> g_colorstore;
+mutex_wrapper<std::unordered_map<string, color>> g_colorstore;
 
-color g_colorempty{"#00000000"};
-color g_colorblack{"#ff000000"};
-color g_colorwhite{"#ffffffff"};
+const color& g_colorempty{"#00000000"};
+const color& g_colorblack{"#ff000000"};
+const color& g_colorwhite{"#ffffffff"};
 
 color::color(string hex) : m_source(hex) {
   if (hex.empty()) {
@@ -59,16 +58,16 @@ color::operator uint32_t() const {
 const color& color::parse(string input, const color& fallback) {
   if (input.empty()) {
     throw application_error("Cannot parse empty color");
-  }
-  auto it = g_colorstore.find(input);
-  if (it != g_colorstore.end()) {
-    return it->second;
-  } else if ((input = color_util::parse_hex(input)).empty()) {
+  } else if ((input = color_util::parse_hex(move(input))).empty()) {
     return fallback;
   }
 
-  g_colorstore.emplace_hint(it, input, color{input});
-  return g_colorstore.at(input);
+  std::lock_guard<decltype(g_colorstore)> guard(g_colorstore);
+  auto it = g_colorstore.find(input);
+  if (it == g_colorstore.end()) {
+    it = g_colorstore.emplace_hint(it, make_pair(input, color{input}));
+  }
+  return it->second;
 }
 
 const color& color::parse(string input) {