diff --git a/README.md b/README.md
index 568ebed..00dc3de 100644
--- a/README.md
+++ b/README.md
@@ -49,5 +49,6 @@ This will run ctags on every commit.
 
 #### TODO
 
-- real and improved unit testing
+- unit testing
+- fix stack smashing bug (test file: failed_cal.ics)
 - add cli argument that will not show ongoing events, only upcoming events
diff --git a/tests/failed_cal.ics b/tests/failed_cal.ics
new file mode 100644
index 0000000..b5215a3
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+++ b/tests/failed_cal.ics
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