diff --git a/README.md b/README.md
index 9389c91..2b8b1d4 100644
--- a/README.md
+++ b/README.md
@@ -1,18 +1,21 @@
 # xplugin
+
+[![ci](https://github.com/QuantStack/xplugin/actions/workflows/ci.yaml/badge.svg)](https://github.com/QuantStack/xplugin/actions/workflows/ci.yaml)
+
 Generic plugin framework in C++.
 
 ## Features
 
 - [x] Generic plugin framework
-- [x] Abitrary abstract base classes can be used as plugin interface
+- [x] Arbitrary abstract base classes can be used as plugin interface
 - [x] Customizable with custom plugin factories (see examples)
-- [x] Works on Linux, Mac and Windows and emscripten
+- [x] Works on linux, mac, windows and emscripten
 
 ## Usage
 
 ## Example 1
 
-All plugins are derived from a a base class, in the first example `MyPluginBase`.
+All plugins are derived from a base class, in the first example `MyPluginBase`.
 All concrete plugins are derived from `MyPluginBase` and implement the pure virtual function (in this example it is only the `do_something()` function).
 Furthermore, for this example, we assume that all concrete plugins have an empty constructor.
 (see example 2 for a more complex example)
@@ -114,7 +117,7 @@ int main(int argc, char** argv)
 
 We again define a plugin interface `MyOtherPluginBase` and a concrete plugin  implementations `MyOtherPluginA` and `MyOtherPluginB`.
 The difference to the first example is that the concrete plugins have a constructor with arguments.
-But both plugins have the same constructor signature. (see example 3 for a more complex example)
+But both plugins have the same constructor signature.
 
 `my_other_plugin_base.hpp`:
 ```cpp
diff --git a/docs/conf.py.in b/docs/conf.py.in
index b223135..055f09c 100644
--- a/docs/conf.py.in
+++ b/docs/conf.py.in
@@ -10,8 +10,6 @@ project = 'xplugin'
 copyright = '2023, Dr. Thorsten Beier and Johan Mabille'
 author = 'Dr. Thorsten Beier and Johan Mabille'
 
-
-
 # -- General configuration ---------------------------------------------------
 # https://www.sphinx-doc.org/en/master/usage/configuration.html#general-configuration
 
@@ -28,13 +26,9 @@ extensions = [
     'breathe'
 ]
 
-
-
 templates_path = ['_templates']
 exclude_patterns = ['_build', 'Thumbs.db', '.DS_Store', 'breathe/*']
 
-
-
 # -- Options for HTML output -------------------------------------------------
 # https://www.sphinx-doc.org/en/master/usage/configuration.html#options-for-html-output
 
@@ -59,13 +53,11 @@ html_theme_options = {
     'titles_only': False
 }
 # html_logo = ''
-# github_url = ''
-#html_baseurl = 'baZINGA'
-
+github_url = 'https://github.com/QuantStack/xplugin'
+# html_baseurl = ''
 
 html_static_path = []
 
-
 # -- Breathe configuration -------------------------------------------------
 from pathlib import Path
 CMAKE_CURRENT_BINARY_DIR = Path("@CMAKE_CURRENT_BINARY_DIR@")
diff --git a/examples/custom_factory_with_metadata/custom_factory_with_metadata_plugin_base.hpp b/examples/custom_factory_with_metadata/custom_factory_with_metadata_plugin_base.hpp
index d8af6fe..040e75d 100644
--- a/examples/custom_factory_with_metadata/custom_factory_with_metadata_plugin_base.hpp
+++ b/examples/custom_factory_with_metadata/custom_factory_with_metadata_plugin_base.hpp
@@ -1,4 +1,6 @@
-#pragma once
+#ifndef CUSTOM_FACTORY_WITH_METADATA_PLUGIN_BASE_HPP
+#define CUSTOM_FACTORY_WITH_METADATA_PLUGIN_BASE_HPP
+
 #include <string>
 
 class PluginBase
@@ -24,3 +26,5 @@ class PluginFactoryBase
     virtual std::string description() const = 0;
     virtual std::string version() const = 0;
 };
+
+#endif // CUSTOM_FACTORY_WITH_METADATA_PLUGIN_BASE_HPP
diff --git a/include/xplugin/xfactory.hpp b/include/xplugin/xfactory.hpp
index 8f9bad4..0b53f5e 100644
--- a/include/xplugin/xfactory.hpp
+++ b/include/xplugin/xfactory.hpp
@@ -27,9 +27,7 @@ class xfactory_base
 {
   public:
     using base_type = BASE_TYPE;
-    virtual ~xfactory_base()
-    {
-    }
+    virtual ~xfactory_base() = default;
     virtual std::unique_ptr<base_type> create(ARGS...) = 0;
 };
 
@@ -41,9 +39,7 @@ class xfactory : public xfactory_base<BASE_TYPE, ARGS...>
     using concrete_type = CONCRETE_TYPE;
     using base_type = BASE_TYPE;
     using factory_base_type = xfactory_base<BASE_TYPE, ARGS...>;
-    virtual ~xfactory()
-    {
-    }
+    virtual ~xfactory() = default;
     std::unique_ptr<base_type> create(ARGS... args) override;
 };
 
diff --git a/include/xplugin/xshared_library.hpp b/include/xplugin/xshared_library.hpp
index b2f12aa..ef63bad 100644
--- a/include/xplugin/xshared_library.hpp
+++ b/include/xplugin/xshared_library.hpp
@@ -6,7 +6,6 @@
  *                                                                          *
  * The full license is in the file LICENSE, distributed with this software. *
  ****************************************************************************/
-#pragma once
 #ifndef XPLUGIN_XSHARED_LIBRARY_HPP
 #define XPLUGIN_XSHARED_LIBRARY_HPP