diff --git a/pyproject.toml b/pyproject.toml
index f217532..5feb0e7 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,7 +1,7 @@
 [tool.poetry]
 
 name = "shaperglot"
-version = "0.2.0"
+version = "0.2.1"
 description = "Test font files for OpenType language support"
 
 license = "MIT"
@@ -23,6 +23,8 @@ classifiers = [
     "Operating System :: OS Independent",
     "Programming Language :: Python",
     "Programming Language :: Python :: 3",
+    "Programming Language :: Python :: 3.7",
+    "Programming Language :: Python :: 3.8",
     "Programming Language :: Python :: 3.9",
 ]
 
diff --git a/shaperglot/checks/no_orphaned_marks.py b/shaperglot/checks/no_orphaned_marks.py
index 28c6867..c145d06 100644
--- a/shaperglot/checks/no_orphaned_marks.py
+++ b/shaperglot/checks/no_orphaned_marks.py
@@ -1,4 +1,4 @@
-from functools import cache
+from functools import lru_cache
 
 from youseedee import ucd_data
 
@@ -7,7 +7,7 @@
 from .common import shaping_input_schema, ShaperglotCheck, check_schema
 
 
-@cache
+@lru_cache(maxsize=None)
 def _simple_mark_check(codepoint):
     return ucd_data(codepoint).get("General_Category") == "Mn"