diff --git a/hexlib/misc.py b/hexlib/misc.py
index bfce03f..71338ca 100644
--- a/hexlib/misc.py
+++ b/hexlib/misc.py
@@ -1,5 +1,7 @@
 import time
 
+import siphash
+
 last_time_called = dict()
 
 
@@ -22,3 +24,13 @@ def rate_limit(per_second):
 
     return decorate
 
+
+Key = b"0123456789ABCDEF"
+
+
+def strhash(str):
+    return siphash.SipHash24(Key, str.encode()).hash()
+
+
+def signed64(i):
+    return -(i & 0x8000000000000000) | (i & 0x7fffffffffffffff)
diff --git a/requirements.txt b/requirements.txt
index acc8ad3..ebe324d 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,2 +1,3 @@
 ImageHash
-influxdb
\ No newline at end of file
+influxdb
+siphash