diff --git a/lmfdb/__init__.py b/lmfdb/__init__.py
index 1d820b53b6..88a80799f2 100644
--- a/lmfdb/__init__.py
+++ b/lmfdb/__init__.py
@@ -1,4 +1,11 @@
 # -*- coding: utf-8 -*-
 
+# psycodict was added as a dependency on May 10, 2024; we provide a useful error message for people upgrading
+try:
+    import psycodict
+except ImportError:
+    print('Missing dependency; try running "sage -pip install -r requirements.txt" in the LMFDB home folder.')
+    raise
+
 from .lmfdb_database import db
 assert db