diff --git a/features/execute.feature b/features/execute.feature
index d8271585..ba04ce0e 100644
--- a/features/execute.feature
+++ b/features/execute.feature
@@ -5,11 +5,32 @@ Feature: execute
     Given a basic setup with a puppet module "puppet-test" from "awesome"
     Then the file "modules/awesome/puppet-test/metadata.json" should not exist
     When I successfully run `msync exec --verbose /bin/true`
-    Then the output should contain "Cloning from 'file://"
+    Then the stdout should contain "Cloning from 'file://"
     And the file "modules/awesome/puppet-test/metadata.json" should exist
 
   @no-clobber
   Scenario: No clones before running command when sourcecode have already been cloned
     Then the file "modules/awesome/puppet-test/metadata.json" should exist
     When I successfully run `msync exec --verbose /bin/true`
-    Then the output should not contain "Cloning from 'file://"
+    Then the stdout should not contain "Cloning from 'file://"
+
+  Scenario: When command run fails, abort expect --no-fail-fast
+
+  @wip
+  Scenario: Show fail-fast default value in help
+    When I successfully run `msync help exec`
+    Then the stdout should contain:
+    """
+          [--fail-fast], [--no-fail-fast]                # Abort the run after a command execution failure
+                                                         # Default: true
+    """
+
+  @wip
+  Scenario: Override fail-fast default value using config file
+    Given the global option "fail_fast" sets to "false"
+    When I successfully run `msync help exec`
+    Then the stdout should contain:
+    """
+          [--fail-fast], [--no-fail-fast]                # Abort the run after a command execution failure
+    """
+    # NOTE: It seems there is a Thor bug here: default value is missing in help when sets to 'false'
diff --git a/lib/modulesync.rb b/lib/modulesync.rb
index 5c130faa..f740ce76 100644
--- a/lib/modulesync.rb
+++ b/lib/modulesync.rb
@@ -190,6 +190,7 @@ def self.clone(cli_options)
   def self.execute(cli_options)
     @options = config_defaults.merge(cli_options)
 
+    errors = {}
     managed_modules.each do |puppet_module|
       $stdout.puts "#{puppet_module.given_name}:"
 
@@ -206,13 +207,24 @@ def self.execute(cli_options)
       FileUtils.chdir(puppet_module.working_directory) do
         result = system command_env, *command_args, unsetenv_others: true
         unless result
-          raise Thor::Error,
-                "Error during script execution ('#{@options[:command_args].join ' '}': #{$CHILD_STATUS})"
+          message = "Command execution failed ('#{@options[:command_args].join ' '}': #{$CHILD_STATUS})"
+          raise Thor::Error, message if @options[:fail_fast]
+
+          errors.merge(
+            puppet_module.given_name => message
+          )
+          $stderr.puts message
         end
       end
 
       $stdout.puts ''
     end
+
+    errors.each do |name, message|
+      puts "#{name}: #{message}"
+    end
+
+    exit 1 unless errors.empty?
   end
 
   def self.reset(cli_options)
diff --git a/lib/modulesync/cli.rb b/lib/modulesync/cli.rb
index 3ba5c090..fbf21a9a 100644
--- a/lib/modulesync/cli.rb
+++ b/lib/modulesync/cli.rb
@@ -38,7 +38,7 @@ class Base < Thor
       class_option :project_root,
                    :aliases => '-c',
                    :desc => 'Path used by git to clone modules into.',
-                   :default => CLI.defaults[:project_root] || 'modules'
+                   :default => CLI.defaults[:project_root]
       class_option :git_base,
                    :desc => 'Specify the base part of a git URL to pull from',
                    :default => CLI.defaults[:git_base] || 'git@github.com:'
@@ -148,7 +148,29 @@ def update
         ModuleSync.update(config)
       end
 
-      desc 'execute COMMAND', 'Execute the command in each managed modules'
+      no_commands do
+        def merge_options(command, cli_options, **more_options)
+          options = CLI.defaults
+          puts "DEFAULTS"
+          pp options
+          # options.merge!(options[command.to_sym]) unless options[command.to_sym].nil?
+          # puts "DEFAULTS + COMMAND-DEFAULT"
+          # pp options
+          options.merge! Util.symbolize_keys cli_options
+          puts "DEFAULTS + COMMAND-DEFAULT + CLI"
+          pp options
+          options.merge! more_options
+          puts "DEFAULTS + COMMAND-DEFAULT + CLI + MORE OPTIONS"
+          pp options
+          options.merge! command: command # TODO Remove this
+          puts "DEFAULTS + COMMAND-DEFAULT + CLI + MORE OPTIONS + COMMAND NAME"
+          pp options
+
+          Util.symbolize_keys options
+        end
+      end
+
+      desc 'execute [OPTIONS] -- COMMAND..', 'Execute the command in each managed modules'
       option :configs,
              :aliases => '-c',
              :desc => 'The local directory or remote repository to define the list of managed modules,' \
@@ -159,14 +181,13 @@ def update
              :aliases => '-b',
              :desc => 'Branch name to make the changes in.',
              :default => CLI.defaults[:branch]
-
+      option :fail_fast,
+             :type => :boolean,
+             :desc => 'Abort the run after a command execution failure',
+             :default => CLI.defaults[:fail_fast].nil? ? true : CLI.defaults[:fail_fast]
       def execute(*command_args)
-        config = {
-          :command => 'execute',
-          :command_args => command_args,
-        }.merge(options)
-        config = Util.symbolize_keys(config)
-        ModuleSync.execute(config)
+        #raise unless ARGV.include? '--'
+        ModuleSync.execute merge_options('execute', options, command_args: command_args)
       end
 
       desc 'reset', 'Reset all repositories'