diff --git a/eo-runtime/src/test/java/EOorg/EOeolang/EOio/InputOutputTest.java b/eo-runtime/src/test/java/EOorg/EOeolang/EOio/InputOutputTest.java
index a7a01051f5..6fdf5f2b20 100644
--- a/eo-runtime/src/test/java/EOorg/EOeolang/EOio/InputOutputTest.java
+++ b/eo-runtime/src/test/java/EOorg/EOeolang/EOio/InputOutputTest.java
@@ -869,7 +869,7 @@ void writesToStdoutViaPosixWriteSyscall(@Mktmp final Path temp) throws IOExcepti
             MatcherAssert.assertThat(
                 "The posix 'write' syscall should have written to standard output, but it didn't",
                 Files.readString(Paths.get(file.getAbsolutePath()), StandardCharsets.UTF_8),
-                Matchers.equalTo(msg)
+                Matchers.containsString(msg)
             );
         }