try git ref

Jenkinsfile

@@ -13,5 +13,16 @@ pipeline {
                 sh "podman build -t docker.io/thallian/atuin:${env.GIT_REF} ."
             }
         }
+        stage('Push') {
+            when { tag "*" }
+            steps {
+                withCredentials([usernamePassword(credentialsId: 'dockerhub', usernameVariable: 'REG_USERNAME', passwordVariable: 'REG_PASSWORD')]) {
+                    sh '''
+                        podman login docker.io -u $REG_USERNAME -p $REG_PASSWORD
+                        podman push docker.io/thallian/atuin:${GIT_REF}
+                    '''
+                }
+            }
+        }
     }
 }