diff --git a/src/shared/types/CourseMeeting.ts b/src/shared/types/CourseMeeting.ts
index 2e8339f8..62c49f02 100644
--- a/src/shared/types/CourseMeeting.ts
+++ b/src/shared/types/CourseMeeting.ts
@@ -2,6 +2,7 @@ import { Serialized } from 'chrome-extension-toolkit';
 
 /**
  * a map of the days of the week that a class is taught, and the corresponding abbreviation
+ * Don't modify the keys
  */
 export const DAY_MAP = {
     M: 'Monday',