Require docker 17.12.0+

https://docs.docker.com/compose/compose-file/compose-versioning/#version-24

Author: andypost

README.md

@@ -36,8 +36,8 @@
 ## Quickstart
 
 * Install docker for <a href="https://docs.docker.com/install/" target="_blank">Linux</a>, <a href="https://docs.docker.com/docker-for-mac/install/" target="_blank">Mac</a>, <a href="https://docs.docker.com/docker-for-windows/install/" target="_blank">Windows</a>
-  *  Check <a href="https://docs.docker.com/install/linux/linux-postinstall/" target="_blank">post-installation steps for Linux</a>
-* Install <a href="https://docs.docker.com/compose/install/" target="_blank">docker compose</a>
+  *  Check <a href="https://docs.docker.com/install/linux/linux-postinstall/" target="_blank">post-installation steps for Linux</a> version 17.12.0 or later
+* Install <a href="https://docs.docker.com/compose/install/" target="_blank">docker compose</a> version 1.21.0 or later
 
 * Copy **.env.default** to **.env**, more information about enviroment file can be found <a href="https://docs.docker.com/compose/env-file/" target="_blank">docs.docker.com</a>
 * Copy **docker-compose.override.yml.default** to **docker-compose.override.yml**, update parts you want to overwrite.

docker/docker-compose.override.yml.default

@@ -1,4 +1,4 @@
-version: "2.1"
+version: "2.4"
 
 services:
 

docker/docker-compose.yml

@@ -1,4 +1,4 @@
-version: "2.1"
+version: "2.4"
 
 services: