diff --git a/src/test/java/io/foldright/showcases/CompletableFutureUsageShowcaseTest.kt b/src/test/java/io/foldright/showcases/CompletableFutureUsageShowcaseTest.kt
index ca256053..1cda28e5 100644
--- a/src/test/java/io/foldright/showcases/CompletableFutureUsageShowcaseTest.kt
+++ b/src/test/java/io/foldright/showcases/CompletableFutureUsageShowcaseTest.kt
@@ -5,7 +5,7 @@ import io.foldright.testutils.*
 import io.kotest.core.spec.style.FunSpec
 import io.kotest.matchers.booleans.shouldBeFalse
 import io.kotest.matchers.collections.shouldHaveSize
-import io.kotest.matchers.longs.shouldBeGreaterThanOrEqual
+import io.kotest.matchers.longs.shouldBeBetween
 import io.kotest.matchers.nulls.shouldBeNull
 import io.kotest.matchers.shouldBe
 import io.kotest.matchers.shouldNotBe
@@ -322,7 +322,7 @@ class CompletableFutureUsageShowcaseTest : FunSpec({
 
     test("delay execution") {
         val tick = currentTimeMillis()
-        val delay = 3L
+        val delay = 5L
 
         val delayer = CompletableFuture.delayedExecutor(delay, TimeUnit.MILLISECONDS)
 
@@ -330,7 +330,8 @@ class CompletableFutureUsageShowcaseTest : FunSpec({
         val duration = CompletableFuture.supplyAsync({
             currentTimeMillis() - tick
         }, delayer).get()
-        duration shouldBeGreaterThanOrEqual 10
+
+        duration.shouldBeBetween(delay, delay + 2)
     }
 
     xtest("performance CF then*").config(invocations = 10) {