diff --git a/.travis.yml b/.travis.yml
index 1445d46..2d6b034 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,8 +6,9 @@ cache:
 
 matrix:
     include:
-        - php: 5.5
         - php: 5.6
+          env:
+            - COMPOSER_FLAGS='--prefer-lowest'
         - php: 7.0
         - php: 7.1
         - php: 7.2
diff --git a/composer.json b/composer.json
index d5d761f..ce94d1b 100644
--- a/composer.json
+++ b/composer.json
@@ -29,11 +29,9 @@
         "ext-gd": "*"
     },
     "require-dev" : {
-        "codeception/codeception": "^4.1",
+        "codeception/codeception": "^2.4",
         "phpunit/phpunit": "^4.8|^7.1",
-        "squizlabs/php_codesniffer": "^3.4",
-        "codeception/module-asserts": "^1.3",
-        "codeception/module-filesystem": "^1.0"
+        "squizlabs/php_codesniffer": "^3.4"
     },
     "config": {
         "bin-dir": "vendor/bin"