diff --git a/src/main/groovy/com/avast/gradle/dockercompose/ComposeExtension.groovy b/src/main/groovy/com/avast/gradle/dockercompose/ComposeExtension.groovy
index 3b6fc17..1f2e94d 100644
--- a/src/main/groovy/com/avast/gradle/dockercompose/ComposeExtension.groovy
+++ b/src/main/groovy/com/avast/gradle/dockercompose/ComposeExtension.groovy
@@ -89,10 +89,11 @@ class ComposeExtension {
     }
 
     VersionNumber getDockerComposeVersion() {
-        def p = project
+        def p = this.project
+        def env = this.environment
         new ByteArrayOutputStream().withStream { os ->
             p.exec { ExecSpec e ->
-                e.environment = environment
+                e.environment = env
                 e.commandLine composeCommand('--version')
                 e.standardOutput = os
             }