diff --git a/Dockerfile b/Dockerfile
index fb2db76..b1856cb 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM composer:1.10.13 as builder
+FROM composer:2.1.3 as builder
 
 COPY . /opt/phpdoc
 WORKDIR /opt/phpdoc