diff --git a/settings.gradle b/settings.gradle
index 2ec54c4..eae264c 100644
--- a/settings.gradle
+++ b/settings.gradle
@@ -2,10 +2,11 @@ import org.gradle.util.GradleVersion
 import org.gradle.api.GradleScriptException
 
 // required Gradle version
-def minGradleVersion = GradleVersion.version("4.4")
+def minGradleVersion = GradleVersion.version("4.4") // including
+def maxGradleVersion = GradleVersion.version("7.0") // excluding
 
-if (GradleVersion.current() < minGradleVersion)
-    throw new GradleScriptException("build requires Gradle ${minGradleVersion} or later", null)
+if (GradleVersion.current() < minGradleVersion || GradleVersion.current() >= maxGradleVersion)
+    throw new GradleScriptException("build requires Gradle between ${minGradleVersion.version} (including) and ${maxGradleVersion.version} (excluding)", null)
 
 include 'oeffi'
 include 'public-transport-enabler'