diff --git a/extra/io/mmap/mmap-tests.factor b/extra/io/mmap/mmap-tests.factor
index d25097e2b0..57faca01c7 100755
--- a/extra/io/mmap/mmap-tests.factor
+++ b/extra/io/mmap/mmap-tests.factor
@@ -8,8 +8,3 @@ IN: io.mmap.tests
 [ 5 ] [ "mmap-test-file.txt" temp-file dup file-info size>> [ length ] with-mapped-file ] unit-test
 [ "22345" ] [ "mmap-test-file.txt" temp-file ascii file-contents ] unit-test
 [ "mmap-test-file.txt" temp-file delete-file ] ignore-errors
-
-[ ] [ "a" "mmap-grow-test.txt" temp-file ascii set-file-contents ] unit-test
-[ 1 ] [ "mmap-grow-test.txt" temp-file file-info size>> ] unit-test
-[ ] [ "mmap-grow-test.txt" temp-file 100 [ drop ] with-mapped-file ] unit-test
-[ 100 ] [ "mmap-grow-test.txt" temp-file file-info size>> ] unit-test
diff --git a/extra/io/windows/mmap/mmap-tests.factor b/extra/io/windows/mmap/mmap-tests.factor
new file mode 100644
index 0000000000..a8430108e8
--- /dev/null
+++ b/extra/io/windows/mmap/mmap-tests.factor
@@ -0,0 +1,8 @@
+USING: io io.mmap io.files kernel tools.test continuations
+sequences io.encodings.ascii accessors ;
+IN: io.windows.mmap.tests
+
+[ ] [ "a" "mmap-grow-test.txt" temp-file ascii set-file-contents ] unit-test
+[ 1 ] [ "mmap-grow-test.txt" temp-file file-info size>> ] unit-test
+[ ] [ "mmap-grow-test.txt" temp-file 100 [ [ ] change-each ] with-mapped-file ] unit-test
+[ 100 ] [ "mmap-grow-test.txt" temp-file file-info size>> ] unit-test