diff --git a/sbt/src/sbt-test/project/sequential/build.sbt b/sbt/src/sbt-test/project/sequential/build.sbt
index 1cc79681e..f3b423d13 100644
--- a/sbt/src/sbt-test/project/sequential/build.sbt
+++ b/sbt/src/sbt-test/project/sequential/build.sbt
@@ -20,6 +20,7 @@ lazy val root = project.
     },
     testFile := target.value / "test.txt",
     sideEffect0 := {
+      Thread.sleep(100)
       val t = testFile.value
       IO.append(t, "0")
     },