diff --git a/app/build.gradle b/app/build.gradle
index 2581444415..d43c8014f9 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -53,8 +53,8 @@ application {
 }
 
 java {
-    sourceCompatibility = 21
-    targetCompatibility = 21
+    sourceCompatibility = 17
+    targetCompatibility = 17
 }
 
 ext {
diff --git a/common/build.gradle b/common/build.gradle
index 53a38c9cc3..5a715e9070 100644
--- a/common/build.gradle
+++ b/common/build.gradle
@@ -48,8 +48,8 @@ dependencies {
 }
 
 java {
-    sourceCompatibility = 21
-    targetCompatibility = 21
+    sourceCompatibility = 17
+    targetCompatibility = 17
 }
 
 ext {
diff --git a/connector/build.gradle b/connector/build.gradle
index 9bc9d2928f..eeb83ef26d 100644
--- a/connector/build.gradle
+++ b/connector/build.gradle
@@ -47,8 +47,8 @@ dependencies {
 }
 
 java {
-    sourceCompatibility = 21
-    targetCompatibility = 21
+    sourceCompatibility = 17
+    targetCompatibility = 17
 }
 
 ext {
diff --git a/fs/build.gradle b/fs/build.gradle
index 5c60777c9d..4c9d3db81d 100644
--- a/fs/build.gradle
+++ b/fs/build.gradle
@@ -48,8 +48,8 @@ dependencies {
 }
 
 java {
-    sourceCompatibility = 21
-    targetCompatibility = 21
+    sourceCompatibility = 17
+    targetCompatibility = 17
 }
 
 ext {
diff --git a/gui/build.gradle b/gui/build.gradle
index 0224021742..70d1f840dc 100644
--- a/gui/build.gradle
+++ b/gui/build.gradle
@@ -27,8 +27,8 @@ repositories {
 }
 
 java {
-    sourceCompatibility = 21
-    targetCompatibility = 21
+    sourceCompatibility = 17
+    targetCompatibility = 17
 }
 
 javafx {
diff --git a/it/build.gradle b/it/build.gradle
index 8faa8819cd..8cc3ed23cc 100644
--- a/it/build.gradle
+++ b/it/build.gradle
@@ -39,8 +39,8 @@ dependencies {
 }
 
 java {
-    sourceCompatibility = 21
-    targetCompatibility = 21
+    sourceCompatibility = 17
+    targetCompatibility = 17
 }
 
 ext {