diff --git a/legacy/.gitignore b/legacy/.gitignore
index 69471bea6..279935729 100644
--- a/legacy/.gitignore
+++ b/legacy/.gitignore
@@ -8,6 +8,10 @@
 /tests/results.html
 /tests/test_results.xml
 
+# Tools
+/tools/
+.php-cs-fixer.cache
+
 ## Github Composer .gitignore
 ## See https://github.com/github/gitignore/blob/master/Composer.gitignore
 ################################################################################
diff --git a/legacy/.php-cs-fixer.php b/legacy/.php-cs-fixer.php
new file mode 100644
index 000000000..7e24cf328
--- /dev/null
+++ b/legacy/.php-cs-fixer.php
@@ -0,0 +1,15 @@
+<?php
+
+$finder = PhpCsFixer\Finder::create()
+    ->in(__DIR__)
+    ->exclude('application/models/airtime/map')
+    ->exclude('application/models/airtime/om');
+
+$config = new PhpCsFixer\Config();
+return $config->setRules([
+    '@PhpCsFixer' => true,
+    'concat_space' => ['spacing' => 'one'],
+    'ordered_class_elements' => false,
+    'yoda_style' => false,
+])
+    ->setFinder($finder);
diff --git a/legacy/Makefile b/legacy/Makefile
index 664e1d9d5..3bb5ac27f 100644
--- a/legacy/Makefile
+++ b/legacy/Makefile
@@ -1,4 +1,4 @@
-.PHONY: build
+.PHONY: build php-cs-fixer
 
 SHELL = bash
 
@@ -10,3 +10,10 @@ test: vendor
 
 build:
 	composer install --no-progress --no-interaction --no-dev
+
+tools/php-cs-fixer:
+	mkdir -p tools/php-cs-fixer
+	composer require --working-dir=tools/php-cs-fixer friendsofphp/php-cs-fixer
+
+php-cs-fixer: tools/php-cs-fixer
+	tools/php-cs-fixer/vendor/bin/php-cs-fixer fix