diff --git a/fladle-plugin/src/main/java/com/osacky/flank/gradle/FladlePluginDelegate.kt b/fladle-plugin/src/main/java/com/osacky/flank/gradle/FladlePluginDelegate.kt
index ea878e0f..aa6dccd8 100644
--- a/fladle-plugin/src/main/java/com/osacky/flank/gradle/FladlePluginDelegate.kt
+++ b/fladle-plugin/src/main/java/com/osacky/flank/gradle/FladlePluginDelegate.kt
@@ -23,10 +23,12 @@ class FladlePluginDelegate {
     val extension = target.extensions.create<FlankGradleExtension>("fladle", target.objects)
 
     target.tasks.register("flankAuth", FlankJavaExec::class.java) {
+      val fladleConfig = target.configurations.getByName(FLADLE_CONFIG)
+      val fladleDir = target.layout.buildDirectory.dir("fladle")
       doFirst {
-        target.layout.fladleDir.get().asFile.mkdirs()
+        fladleDir.get().asFile.mkdirs()
       }
-      classpath = project.fladleConfig
+      classpath = fladleConfig
       args = listOf("auth", "login")
     }
 
diff --git a/fladle-plugin/src/main/java/com/osacky/flank/gradle/FlankJavaExec.kt b/fladle-plugin/src/main/java/com/osacky/flank/gradle/FlankJavaExec.kt
index f10ef850..5148f1aa 100644
--- a/fladle-plugin/src/main/java/com/osacky/flank/gradle/FlankJavaExec.kt
+++ b/fladle-plugin/src/main/java/com/osacky/flank/gradle/FlankJavaExec.kt
@@ -10,12 +10,12 @@ import javax.inject.Inject
 )
 open class FlankJavaExec
   @Inject
-  constructor(projectLayout: ProjectLayout) : JavaExec() {
+  constructor(private val projectLayout: ProjectLayout) : JavaExec() {
     init {
       group = FladlePluginDelegate.TASK_GROUP
       mainClass.set("ftl.Main")
       workingDir(projectLayout.fladleDir)
     }
 
-    fun setUpWorkingDir(configName: String) = workingDir(project.layout.buildDirectory.dir("fladle/$configName"))
+    fun setUpWorkingDir(configName: String) = workingDir(projectLayout.buildDirectory.dir("fladle/$configName"))
   }
diff --git a/fladle-plugin/src/test/java/com/osacky/flank/gradle/integration/ConfigurationCacheTest.kt b/fladle-plugin/src/test/java/com/osacky/flank/gradle/integration/ConfigurationCacheTest.kt
index 2f9b5582..67ffb66c 100644
--- a/fladle-plugin/src/test/java/com/osacky/flank/gradle/integration/ConfigurationCacheTest.kt
+++ b/fladle-plugin/src/test/java/com/osacky/flank/gradle/integration/ConfigurationCacheTest.kt
@@ -90,6 +90,30 @@ class ConfigurationCacheTest {
     assertThat(secondResult.output).contains("Reusing configuration cache.")
   }
 
+  @Test
+  fun flankAuth() {
+    writeBuildGradle(
+      """|plugins {
+           |  id "com.osacky.fladle"
+           |}
+           |
+           |repositories {
+           |  mavenCentral()
+           |}
+           |
+      """.trimMargin(),
+    )
+    val result = configCachingRunner("flankAuth").buildAndFail()
+
+    assertThat(result.output).contains("Address already in use")
+    assertThat(result.output).contains("Configuration cache entry stored.")
+
+    val secondResult = configCachingRunner("flankAuth").buildAndFail()
+
+    assertThat(secondResult.output).contains("Address already in use")
+    assertThat(secondResult.output).contains("Reusing configuration cache.")
+  }
+
   @Test
   fun runFlank() {
     writeBuildGradle(