diff --git a/.drone.yml b/.drone.yml
index ac4d20bd..e4c559bd 100644
--- a/.drone.yml
+++ b/.drone.yml
@@ -8,7 +8,7 @@ pipeline:
     image: nextcloudci/php7.0:php7.0-2
     environment:
       - APP_NAME=survey_client
-      - CORE_BRANCH=master
+      - CORE_BRANCH=stable15
       - DB=sqlite
     commands:
       - wget https://raw.githubusercontent.com/nextcloud/travis_ci/master/before_install.sh
diff --git a/.travis.yml b/.travis.yml
index 519075f4..ecb07636 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,7 +6,7 @@ language: php
 
 env:
   global:
-    - CORE_BRANCH=master
+    - CORE_BRANCH=stable15
     - APP_NAME=survey_client
 #  matrix:
 #    - DB=sqlite