diff --git a/src/main/kotlin/com/beust/kobalt/internal/JvmCompiler.kt b/src/main/kotlin/com/beust/kobalt/internal/JvmCompiler.kt
index c46b9261..7ffd4bda 100644
--- a/src/main/kotlin/com/beust/kobalt/internal/JvmCompiler.kt
+++ b/src/main/kotlin/com/beust/kobalt/internal/JvmCompiler.kt
@@ -52,7 +52,7 @@ class JvmCompiler @Inject constructor(val dependencyManager: DependencyManager)
 
     private fun runClasspathContributors(project: Project?, context: KobaltContext?) :
             Collection<IClasspathDependency> {
-        val result = arrayListOf<IClasspathDependency>()
+        val result = hashSetOf<IClasspathDependency>()
         context!!.pluginInfo.classpathContributors.forEach { it: IClasspathContributor ->
             result.addAll(it.entriesFor(project))
         }