diff --git a/composer.json b/composer.json
index d0ff015..3d869b6 100644
--- a/composer.json
+++ b/composer.json
@@ -10,5 +10,12 @@
   "minimum-stability": "dev",
   "require": {
     "drupal/core": "~8"
+  },
+  "extra": {
+    "drush": {
+      "services": {
+        "drush.services.yml": "^9 || ^10"
+      }
+    }
   }
 }
diff --git a/drush.services.yml b/drush.services.yml
new file mode 100644
index 0000000..91ef2da
--- /dev/null
+++ b/drush.services.yml
@@ -0,0 +1,6 @@
+services:
+  bs_lib.commands:
+    class: \Drupal\bs_lib\Commands\BsLibCommands
+    arguments: ['@theme_handler']
+    tags:
+      - { name: drush.command }
diff --git a/src/Commands/BsLibCommands.php b/src/Commands/BsLibCommands.php
new file mode 100644
index 0000000..4d15e0d
--- /dev/null
+++ b/src/Commands/BsLibCommands.php
@@ -0,0 +1,699 @@
+<?php
+
+namespace Drupal\bs_lib\Commands;
+
+use Drupal\Component\Serialization\Yaml;
+use Drupal\Core\Extension\ThemeHandlerInterface;
+use Drush\Commands\DrushCommands;
+use Exception;
+use stdClass;
+
+/**
+ * Drush commands for bs_lib module.
+ */
+class BsLibCommands extends DrushCommands {
+
+  /**
+   * BsLibCommands constructor.
+   */
+  public function __construct(ThemeHandlerInterface $theme_hanldler) {
+    // For easier maintenance we just wrap the methods from bs_base here.
+    $bs_base = $theme_hanldler->getTheme('bs_base');
+    include_once "{$bs_base->getPath()}/bs_base.drush.inc";
+  }
+
+  /**
+   * Create a new bs_base compatible child theme.
+   *
+   * @command bs:theme-create
+   *
+   * @param string $parent_machine_name Parent theme machine name.
+   * @param string $child_machine_name Child theme machine name.
+   * @param string $child_name Child theme name.
+   * @param string $child_description Child theme description.
+   *
+   * @bootstrap root
+   * @aliases bs-tc,bs-theme-create
+   *
+   * @usage drush bs-tc bs_bootstrap custom_theme 'Custom theme' 'Custom theme description'
+   *   Create a new bs_base compatible child theme.
+   *
+   * @throws \Exception
+   */
+  public function themeCreate($parent_machine_name, $child_machine_name, $child_name, $child_description) {
+    // Verify that the child machine name contains no disallowed characters.
+    if (preg_match('@[^a-z0-9_]+@', $child_machine_name)) {
+      $this->logger()->error('The machine-readable name "' . $child_machine_name . '" must contain only lowercase letters, numbers, and hyphens.');
+      return;
+    }
+
+    $this->logger()->info("Starting $child_machine_name theme creation");
+
+    // Parent theme should exist.
+    $parent_path = $this->drupalGetThemePath($parent_machine_name);
+    if (empty($parent_path)) {
+      throw new \Exception('Parent theme does not exist.');
+    }
+
+    // Child theme should not exist.
+    if (!empty($child_path = $this->drupalGetThemePath($child_machine_name))) {
+      throw new \Exception("Child theme already exist on $child_path file system.");
+    }
+
+    // Create child theme directory.
+    $child_path = 'themes/custom/' . $child_machine_name;
+    if (!mkdir($child_path, 0755, TRUE)) {
+      throw new \Exception("Failed to create child theme directory on $child_path path.");
+    }
+
+    $options = [
+      'parent_machine_name' => $parent_machine_name,
+      'parent_path' => $parent_path,
+      'child_machine_name' => $child_machine_name,
+      'child_path' => $child_path,
+      'child_name' => $child_name,
+      'child_description' => $child_description,
+    ];
+
+    // Copy files from parent and change/apply text changes to labels.
+    $this->copyThemeFiles($options);
+
+    // Replace text in copied files.
+    $this->reconfigureThemeFiles($options);
+
+    // Copy theme-options.yml from parent theme. Try first to copy template if
+    // it exist, if not copy theme-options.yml.
+    $theme_options_filename = FALSE;
+    if (file_exists($options['parent_path'] . '/template.theme-options.yml')) {
+      $theme_options_filename = 'template.theme-options.yml';
+    }
+    elseif (file_exists($options['parent_path'] . '/theme-options.yml')) {
+      $theme_options_filename = 'theme-options.yml';
+    }
+    if ($theme_options_filename && !copy($options['parent_path'] . '/' . $theme_options_filename, $options['child_path'] . '/' . 'theme-options.yml')) {
+      throw new \Exception("Failed to copy $theme_options_filename file from {$options['parent_path']} to {$options['child_path']}.");
+    }
+
+    // Generate some files from the scratch.
+    $this->generateFile("config/schema/{$child_machine_name}.schema.yml", $options);
+    $this->generateFile('gulp-options.yml', $options);
+    $this->generateFile($child_machine_name . '.info.yml', $options);
+    $this->generateFile($child_machine_name . '.libraries.yml', $options);
+    $this->generateFile('README.md', $options);
+
+    // Rebuild themes static cache because new theme is created.
+    $this->drupalThemeListInfo(TRUE);
+
+    // Make sure we are on latest parent theme versions.
+    $update_functions = $this->GetUpdateHooks($child_machine_name);
+    if (!empty($update_functions)) {
+      $bs_versions = [];
+      foreach ($update_functions as $theme_name => $theme_updates) {
+        // Get last update.
+        end($theme_updates['functions']);
+        $last_function = key($theme_updates['functions']);
+        $bs_versions['bs_versions.' . $theme_name] = (int) $last_function;
+      }
+
+      $all_themes = $this->drupalThemeListInfo();
+      $this->setYmlValue($all_themes[$child_machine_name]->pathname, $bs_versions, TRUE);
+    }
+
+    // Update and flatten SASS files.
+    $this->updateSassFiles($child_machine_name);
+
+    // Rebuild CSS files.
+    $this->themeBuild($child_machine_name);
+  }
+
+  /**
+   * Update existing bs_lib compatible child theme.
+   *
+   * @command bs:theme-update
+   *
+   * @param string $target_machine_name Theme machine name.
+   * @bootstrap root
+   * @aliases bs-tu,bs-theme-update
+   *
+   * @usage drush bs-tu custom_theme
+   *   Create a new bs_base compatible child theme.
+   * @throws \Exception
+   */
+  public function themeUpdate($target_machine_name) {
+    $this->logger()->info("Updating a $target_machine_name theme");
+
+    $target_path = $this->drupalGetThemePath($target_machine_name);
+    if (empty($target_path)) {
+      $this->logger()->error('Target theme does not exist.');
+      return;
+    }
+
+    $parent_themes = $this->getParentThemes($target_machine_name);
+    if (empty($parent_themes)) {
+      $this->logger()->error('Parent themes are missing.');
+      return;
+    }
+
+    // Run update hooks.
+    $this->themeRunUpdateHooks($target_machine_name);
+
+    $all_themes = $this->drupalThemeListInfo();
+    $first_parent_machine_name = $this->drupalGetParentThemeName($target_machine_name);
+
+    $this->updateSassFiles($target_machine_name);
+
+    // Check for any new or removed CSS library in parent theme and update
+    // libraries-override section.
+    $parent_theme_libraries_override = $this->generateLibrariesOverride($first_parent_machine_name);
+    $target_info_array = $all_themes[$target_machine_name]->info;
+    $target_theme_libraries_override = $target_info_array['libraries-override'];
+    // Keep only the libraries from target that are not from parents.
+    foreach ($target_theme_libraries_override as $library_key => $library_value) {
+      // We have it in parent already.
+      if (isset($parent_theme_libraries_override[$library_key])) {
+        unset($target_theme_libraries_override[$library_key]);
+      }
+      // We do not have it in parent but it does belong to parent themes. We
+      // assume that library was removed from parent theme or that it is in
+      // parent parents. In this case we will remove it from here.
+      elseif ($this->libraryKeyComingFromParents($library_key, $target_machine_name)) {
+        unset($target_theme_libraries_override[$library_key]);
+      }
+    }
+    // We start from parent generated libraries override.
+    $new_libraries_override = array_merge($parent_theme_libraries_override, $target_theme_libraries_override);
+    // Update info file with new libraries override.
+    $info_content = file_get_contents($all_themes[$target_machine_name]->pathname);
+    $info_content = preg_replace('/^libraries-override:\R(^ +.+\R)+/m', Yaml::encode(['libraries-override' => $new_libraries_override]), $info_content);
+    file_put_contents($all_themes[$target_machine_name]->pathname, $info_content);
+
+    // Rebuild CSS files.
+    $this->themeBuild($target_machine_name);
+  }
+
+  /**
+   * Download theme package.json dependencies with yarn, build theme CSS files.
+   *
+   * @command bs:theme-build
+   *
+   * @param string $theme_machine_name Theme machine name.
+   * @bootstrap root
+   * @aliases bs-tb,bs-theme-build
+   *
+   * @usage drush bs-tb custom_theme
+   *   Download custom_theme build dependencies and build all CSS files.
+   */
+  public function themeBuild($theme_machine_name) {
+    $this->logger()->info("Building CSS asset for a $theme_machine_name theme");
+
+    $target_path = $this->drupalGetThemePath($theme_machine_name);
+    if (empty($target_path)) {
+      $this->logger()->error("Target theme {$theme_machine_name} does not exist.");
+      return;
+    }
+
+    $this->drushBuildCss($target_path);
+  }
+
+  /**
+   * Returns array with unique lines.
+   *
+   * This will eliminate all duplicate lines in array but it will also compare
+   * commented lines with not commented and eliminate that duplicates also. For
+   * example:
+   *
+   * array(
+   *   '@import "bs_bootstrap/sass/components/partials/alert";',
+   *   '//@import "bs_bootstrap/sass/components/partials/alert";',
+   * )
+   *
+   * This two values are considered duplicates also and the result will be
+   *
+   * array(
+   *   '//@import "bs_bootstrap/sass/components/partials/alert";',
+   * )
+   *
+   * @param array $lines
+   *   Array of lines.
+   *
+   * @return array
+   *   Array of unique lines.
+   */
+  protected function arrayUniqueLines(array $lines) {
+    return _bs_base_array_unique_lines($lines);
+  }
+
+  /**
+   * Copy general theme files from parent theme to child theme.
+   *
+   * @param array $options
+   *   Array of options having next keys:
+   *   - parent_machine_name
+   *   - parent_path
+   *   - child_path
+   *   - child_name
+   *   - child_description.
+   */
+  protected function copyThemeFiles(array $options) {
+    _bs_base_copy_theme_files($options);
+  }
+
+  /**
+   * Copy file from parent theme to child theme.
+   *
+   * If parent file is a directory then it will be created.
+   *
+   * Target sub-directories of a file will be created automatically if they do not
+   * exists.
+   *
+   * @param string $file
+   *   File name.
+   * @param array $options
+   *   Array of options having next keys:
+   *   - parent_machine_name
+   *   - parent_path
+   *   - child_machine_name
+   *   - child_path.
+   *
+   * @return bool
+   *   TRUE if the file was copied, FALSE otherwise.
+   */
+  protected function copyFile($file, array $options) {
+    return _bs_base_copy_file($file, $options);
+  }
+
+  /**
+   * Finds all the base themes for the specified theme.
+   *
+   * @param array $themes
+   *   An array of available themes.
+   * @param string $theme
+   *   The name of the theme whose base we are looking for.
+   *
+   * @return array
+   *   Returns an array of all of the theme's ancestors including specified
+   *   theme.
+   */
+  protected function drupalGetBaseThemes(array $themes, $theme) {
+    return _bs_base_drupal_get_base_themes($themes, $theme);
+  }
+
+  /**
+   * Returns the first parent theme of passed child theme.
+   *
+   * @param string $theme_name
+   *   The name of the child theme whose first parent theme we are looking for.
+   *
+   * @return string|NULL
+   *   Returns a theme machine name of first parent theme or NULL if parent does
+   *   not exist.
+   */
+  protected function drupalGetParentThemeName($theme_name) {
+    return _bs_base_drupal_get_parent_theme_name($theme_name);
+  }
+
+  /**
+   * Returns the path to a Drupal theme.
+   *
+   * @param string $name
+   *   Theme machine name.
+   *
+   * @return string
+   *   The path to the requested theme or an empty string if the item is not
+   *   found.
+   */
+  protected function drupalGetThemePath($name) {
+    return _bs_base_drupal_get_theme_path($name);
+  }
+
+  /**
+   * Discovers available extensions of a given type.
+   *
+   * For an explanation of how this work see ExtensionDiscovery::scan().
+   *
+   * @param string $type
+   *   The extension type to search for. One of 'profile', 'module', 'theme', or
+   *   'theme_engine'.
+   * @param bool $reset
+   *   Reset internal cache.
+   *
+   * @return stdClass[]
+   *   An associative array of stdClass objects, keyed by extension name.
+   */
+  protected function drupalScan($type, $reset = FALSE) {
+    return _bs_base_drupal_scan($type, $reset);
+  }
+
+  /**
+   * Recursively scans a base directory for the extensions it contains.
+   *
+   * @see ExtensionDiscovery::scanDirectory()
+   *   For an explanation of how this works.
+   *
+   * @param string $dir
+   *   A relative base directory path to scan, without trailing slash.
+   *
+   * @return stdClass[]
+   *   An associative array of stdClass objects, keyed by extension name.
+   */
+  protected function drupalScanDirectory($dir) {
+    return _bs_base_drupal_scan_directory($dir);
+  }
+
+  /**
+   * Get information's for all themes.
+   *
+   * @param bool $reset
+   *   Reset internal cache.
+   *
+   * @return array
+   *   Array holding themes information's.
+   */
+  protected function drupalThemeListInfo($reset = FALSE) {
+    return _bs_base_drupal_theme_list_info($reset);
+  }
+
+  /**
+   * Finds all parent themes for the specified theme.
+   *
+   * @param string $theme_machine_name
+   *   The machine name of the theme whose parent themes we are looking for.
+   *
+   * @return array
+   *   Returns an array of all of the parent themes.
+   */
+  protected function getParentThemes($theme_machine_name) {
+    return _bs_base_get_parent_themes($theme_machine_name);
+  }
+
+  /**
+   * Get theme information.
+   *
+   * @param string $theme_machine_name
+   *   Theme machine name.
+   *
+   * @return mixed|null
+   *   Theme info object or NULL if theme does not exist.
+   */
+  protected function getThemeInfo($theme_machine_name) {
+    return _bs_base_get_theme_info($theme_machine_name);
+  }
+
+  /**
+   * Get all child themes for passed parent_theme.
+   *
+   * @todo Remove? Doesn't seem to be used.
+   *
+   * @param string $parent_theme
+   *   Machine name of parent theme.
+   *
+   * @return array
+   *   Array of all child themes machine names. Empty array if child themes does
+   *   not exist.
+   */
+  protected function findChildThemes($parent_theme) {
+    return _bs_base_find_child_themes($parent_theme);
+  }
+
+  /**
+   * Check that library is coming from theme parent themes or bs_lib module.
+   *
+   * @param string $library_key
+   *   Library key.
+   * @param string $theme_machine_name
+   *   Theme machine name.
+   *
+   * @return bool
+   *   TRUE if library is coming from parents, FALSE other way.
+   */
+  protected function libraryKeyComingFromParents($library_key, $theme_machine_name) {
+    return _bs_base_library_key_coming_from_parents($library_key, $theme_machine_name);
+  }
+
+  /**
+   * Replace text in theme files so all configurations are correct.
+   *
+   * @param array $options
+   *   Array of options having next keys:
+   *   - parent_machine_name
+   *   - parent_path
+   *   - child_path
+   *   - child_name
+   *   - child_description.
+   *
+   * @throws \Exception
+   */
+  protected function reconfigureThemeFiles(array $options) {
+    _bs_base_reconfigure_theme_files($options);
+  }
+
+  /**
+   * Get theme update functions.
+   *
+   * @param string $target_machine_name
+   *   Target theme machine name.
+   *
+   * @return array
+   *   Array of update functions.
+   */
+  protected function getUpdateHooks($target_machine_name) {
+    return _bs_base_get_update_hooks($target_machine_name);
+  }
+
+  /**
+   * Run theme update functions.
+   *
+   * @param string $target_machine_name
+   *   Target theme machine name.
+   *
+   * @throws \Exception
+   */
+  protected function themeRunUpdateHooks($target_machine_name) {
+    return _bs_base_theme_run_update_hooks($target_machine_name);
+  }
+
+  /**
+   * Execute yarn install and gulp sass in provided path.
+   *
+   * @param string $path
+   *   Path to theme folder.
+   */
+  protected function drushBuildCss($path) {
+    _bs_base_drush_build_css($path);
+  }
+
+  /**
+   * Ensure that theme filename has all directories.
+   *
+   * @param string $filename
+   *   Filename with optional subdirectories in path that we ensure they exist.
+   * @param string $path
+   *   Base path in which we will check $filename subdirectories.
+   *
+   * @return bool
+   *   TRUE on success, FALSE on error.
+   */
+  protected function ensureDirectory($filename, $path) {
+    return _bs_base_ensure_directory($filename, $path);
+  }
+
+  /**
+   * Finds all files that match a given mask in a given directory.
+   *
+   * For additional information see file_scan_directory().
+   *
+   * @param string $dir
+   *   The base directory or URI to scan, without trailing slash.
+   * @param string $mask
+   *   The preg_match() regular expression for files to be included.
+   * @param array $options
+   *   An associative array of additional options, with the following elements:
+   *   - 'nomask': The preg_match() regular expression for files to be excluded.
+   *     Defaults to the 'file_scan_ignore_directories' setting.
+   *   - 'callback': The callback function to call for each match. There is no
+   *     default callback.
+   *   - 'recurse': When TRUE, the directory scan will recurse the entire tree
+   *     starting at the provided directory. Defaults to TRUE.
+   *   - 'key': The key to be used for the returned associative array of files.
+   *     Possible values are 'uri', for the file's URI; 'filename', for the
+   *     basename of the file; and 'name' for the name of the file without the
+   *     extension. Defaults to 'uri'.
+   *   - 'min_depth': Minimum depth of directories to return files from. Defaults
+   *     to 0.
+   * @param int $depth
+   *   The current depth of recursion. This parameter is only used internally and
+   *   should not be passed in.
+   *
+   * @return
+   *   An associative array (keyed on the chosen key) of objects with 'uri',
+   *   'filename', and 'name' properties corresponding to the matched files.
+   */
+  protected function fileScanDirectory($dir, $mask, $options = [], $depth = 0) {
+    return _bs_base_file_scan_directory($dir, $mask, $options, $depth);
+  }
+
+  /**
+   * Flatten all parent theme @import directives in a SASS file.
+   *
+   * @param object $target_sass_file
+   *   Target SASS file object.
+   * @param string $target_machine_name
+   *   Target theme machine name.
+   * @param array $current_themes
+   *   Array of current themes.
+   * @param array $parent_themes_sass_files
+   *   Array of all SASS files from parent theme.
+   * @param int $depth
+   *   Current recursion depth, internally used.
+   *
+   * @return array
+   *   Returns array of flattened SASS @import directives.
+   */
+  protected function flattenSassFileImports($target_sass_file, $target_machine_name, array $current_themes, array $parent_themes_sass_files, $depth = 0) {
+    return _bs_base_flatten_sass_file_imports($target_sass_file, $target_machine_name, $current_themes, $parent_themes_sass_files, $depth);
+  }
+
+  /**
+   * Generate child SASS file from parent theme.
+   *
+   * @param object $parent_sass_file
+   *   Plain PHP object holding SASS file information.
+   * @param array $options
+   *   Array of parent/child options.
+   *
+   * @return bool
+   *   TRUE on success, FALSE other way.
+   */
+  protected function generateSassFile($parent_sass_file, array $options) {
+    return _bs_base_generate_sass_file($parent_sass_file, $options);
+  }
+
+  /**
+   * Generate theme file with a default content.
+   *
+   * @param string $file_name
+   *   File name.
+   * @param array $options
+   *   Options array.
+   *
+   * @return bool
+   *   TRUE on success, FALSE on failure.
+   */
+  protected function generateFile($file_name, array $options) {
+    return _bs_base_generate_file($file_name, $options);
+  }
+
+  /**
+   * Get all CSS libraries from passed theme that child theme needs to override.
+   *
+   * @param string $parent_machine_name
+   *   Parent theme machine name.
+   *
+   * @return array
+   *   Libraries override array.
+   */
+  protected function generateLibrariesOverride($parent_machine_name) {
+    return _bs_base_generate_libraries_override($parent_machine_name);
+  }
+
+  /**
+   * Get CSS libraries from theme in libraries override format.
+   *
+   * @param string $theme_machine_name
+   *   Theme machine name from which we are getting CSS libraries.
+   *
+   * @return array
+   *   Arrays of CSS libraries in libraries override format.
+   */
+  protected function getCssLibrariesForOverride($theme_machine_name) {
+    return _bs_base_get_css_libraries_for_override($theme_machine_name);
+  }
+
+  /**
+   * Get array of all SASS files in the given path.
+   *
+   * @param string $path
+   *   Theme path.
+   *
+   * @return array
+   *   Array of all SASS files in the given path.
+   */
+  protected function getSassFiles($path) {
+    return _bs_base_get_sass_files($path);
+  }
+
+  /**
+   * Regular expression search and replace in the text.
+   *
+   * @param string $text
+   *   Text to search and replace.
+   * @param array $regexps
+   *   Array of regexps searches with it replace values.
+   * @param string $modifiers
+   *   PHP regular expression modifiers.
+   * @param string $delimiter
+   *   PHP regular expression delimiter.
+   *
+   * @return string
+   *   Replaced text.
+   */
+  protected function regexp($text, array $regexps, $modifiers = 'm', $delimiter = '%') {
+    return _bs_base_regexp($text,$regexps, $modifiers, $delimiter);
+  }
+
+  /**
+   * Regular expression search and replace in the file.
+   *
+   * @param string $file_name
+   *   File path.
+   * @param array $regexps
+   *   Array of regexps searches with it replace values.
+   *
+   * @return bool
+   *   TRUE on success, FALSE other way.
+   */
+  protected function regexpFile($file_name, array $regexps) {
+    return _bs_base_regexp_file($file_name, $regexps);
+  }
+
+  /**
+   * Set primitive values in a yml file.
+   *
+   * Please note that this implementation is not perfect but exist only to
+   * supportthe needs of this drush implementation. There are couple of
+   * limitations that are explained in function comments. Most importantly
+   * values in values array can be only primitive types for now.
+   *
+   * @param string $path
+   *   Yaml file path.
+   * @param array $values
+   *   Array with yaml values to set. The element key is a combination of yaml
+   *     keys and element value is yaml value. For example:
+   *
+   *     $values['logo:path'] = 'custom/logo/path'
+   *
+   *   will do
+   *
+   *     logo:
+   *       path: 'custom/logo/path'.
+   * @param bool $add
+   *   If TRUE then if value does not exist it will be added.
+   *
+   * @throws Exception
+   *   Throws exception in the case that we try to set non scalar value.
+   */
+  protected function setYmlValue($path, array $values, $add = FALSE) {
+    _bs_base_set_yml_value($path, $values, $add);
+  }
+
+  /**
+   * Update SASS files in theme and do SASS import flattening.
+   *
+   * @param string $theme_machine_name
+   *   Theme machine name.
+   */
+  protected function updateSassFiles($theme_machine_name) {
+    _bs_base_update_sass_files($theme_machine_name);
+  }
+
+}