diff --git a/app/proguard-rules.pro b/app/proguard-rules.pro
index ceae3db4..6688fac0 100644
--- a/app/proguard-rules.pro
+++ b/app/proguard-rules.pro
@@ -18,3 +18,7 @@
 
 -repackageclasses
 -allowaccessmodification
+
+# Gson uses generic type information stored in a class file when working with fields. Proguard
+# removes such information by default, so configure it to keep all of it.
+-keepattributes Signature,InnerClasses