diff --git a/main/src/main/scala/sbt/internal/SysProp.scala b/main/src/main/scala/sbt/internal/SysProp.scala
index fbf0942b2..737b0b368 100644
--- a/main/src/main/scala/sbt/internal/SysProp.scala
+++ b/main/src/main/scala/sbt/internal/SysProp.scala
@@ -218,6 +218,6 @@ object SysProp {
     baseCache.getAbsoluteFile / "v1"
   }
 
-  val sbtCredentialsEnv: Option[Credentials] =
+  lazy val sbtCredentialsEnv: Option[Credentials] =
     sys.env.get("SBT_CREDENTIALS").map(raw => new FileCredentials(new File(raw)))
 }