diff --git a/mbed-tls-pr-merge.yaml b/mbed-tls-pr-merge.yaml
index 3bc2ac3..14dc9c2 100644
--- a/mbed-tls-pr-merge.yaml
+++ b/mbed-tls-pr-merge.yaml
@@ -16,9 +16,15 @@
                   <name>mbedtls-test</name>
                   <retriever class="org.jenkinsci.plugins.workflow.libs.SCMSourceRetriever">
                     <scm class="org.jenkinsci.plugins.github_branch_source.GitHubSCMSource" plugin="github-branch-source@2.9.1">
+                      <credentialsId>mbedtls-github-token</credentialsId>
                       <repoOwner>Mbed-TLS</repoOwner>
                       <repository>mbedtls-test</repository>
                       <repositoryUrl>https://github.com/Mbed-TLS/mbedtls-test.git</repositoryUrl>
+                      <traits>
+                        <org.jenkinsci.plugins.github__branch__source.SSHCheckoutTrait>
+                          <credentialsId>mbedtls-github-ssh</credentialsId>
+                        </org.jenkinsci.plugins.github__branch__source.SSHCheckoutTrait>
+                      </traits>
                     </scm>
                   </retriever>
                   <defaultVersion>main</defaultVersion>
@@ -49,4 +55,6 @@
           disable: false
           recursive: true
           tracking: false
-          parent-credentials: false
+          parent-credentials: true
+        ssh-checkout:
+          credentials: mbedtls-github-ssh