diff --git a/_calendar/generate.py b/_calendar/generate.py
index f0390a6..bae2814 100644
--- a/_calendar/generate.py
+++ b/_calendar/generate.py
@@ -2,6 +2,7 @@
 from ics import Calendar, Event
 import requests
 import os
+import hashlib
 
 
 @dataclass
@@ -49,7 +50,9 @@ def main():
     c = Calendar()
 
     for event in events:
-        e = Event()
+        e = Event(uid="asdasd")
+        e.uid = None # Explicitly remove the auto-generated uid again. Otherwise we can not distinguish between events
+        # that have a default uid or one that is based on the ctftime id.
 
         if event.ctftime_id:
             ctftime = ctftime_event(event.ctftime_id)
@@ -64,9 +67,12 @@ def main():
         e.end = event.end or e.end
         e.location = event.location or e.location
         e.description = event.comment
-        e.uid = e.uid or f"{hash(e.name)}@kitctf.de"
+        e.uid = e.uid or f"{hashlib.sha256(e.name.encode()).hexdigest()}@kitctf.de"
 
         c.events.add(e)
+    uids : list[str] = [e.uid for e in c.events]
+    assert len(uids) == len(set(uids)), "Duplicate UIDs detected" # For future me.
+    assert all(e.uid is not None for e in c.events), "All UIDs should be set" # For future me.
 
     with open(os.path.dirname(os.path.realpath(__file__)) + '/../hack_harder.ics', 'w') as f:
         f.writelines(c.serialize_iter())
diff --git a/hack_harder.ics b/hack_harder.ics
index 35aada8..9e51b1e 100644
--- a/hack_harder.ics
+++ b/hack_harder.ics
@@ -37,9 +37,9 @@ SUMMARY:ENOWARS 7
 UID:2040@ctftime.org
 END:VEVENT
 BEGIN:VEVENT
-DTEND:20240505T130000Z
+DTEND:20240512T130000Z
 LOCATION:https://hacking-meisterschaft.de/
-DTSTART:20240504T130000Z
+DTSTART:20240511T130000Z
 SUMMARY:CyberSecurityRumble Quals
 UID:2224@ctftime.org
 END:VEVENT
@@ -82,7 +82,13 @@ BEGIN:VEVENT
 DTEND:20230930T110000Z
 DTSTART:20230928T110000Z
 SUMMARY:CyberSecurityRumble Finals 2023
-UID:73c76f2d-88d3-4e9b-be28-275addd4bc6d@73c7.org
+UID:254bc97986c9c1e17ed6c58b19067d3f291678c6cfdcbce18202b8e5e9a597ce@kitctf.de
+END:VEVENT
+BEGIN:VEVENT
+DTEND:20230813T000000Z
+DTSTART:20230810T000000Z
+SUMMARY:DEF CON Finals
+UID:19b82d2513f9ee43c5f8a6694c2f06524078a6ebeb8ce376e4445ac17b5a9c2f@kitctf.de
 END:VEVENT
 BEGIN:VEVENT
 DTEND:20230817T220000Z
@@ -106,12 +112,6 @@ SUMMARY:FAUST CTF 2023
 UID:2011@ctftime.org
 END:VEVENT
 BEGIN:VEVENT
-DTEND:20230813T000000Z
-DTSTART:20230810T000000Z
-SUMMARY:DEF CON Finals
-UID:8880306c-6546-4d7b-abbf-2dbb7c201e77@8880.org
-END:VEVENT
-BEGIN:VEVENT
 DTEND:20231029T120000Z
 LOCATION:https://platypwn.ctf.platypwnies.de/
 DTSTART:20231028T120000Z