diff --git a/docs/changelog-develop.md b/docs/changelog-develop.md
index f2d5728..6c7edc5 100644
--- a/docs/changelog-develop.md
+++ b/docs/changelog-develop.md
@@ -2,6 +2,12 @@
 
 This file documents changes on the develop branch of this project.
 
+## 2026-05-28 — Authentication: data models
+
+### Added
+- `User`, `UserSession`, `AuthAudit` SQLAlchemy models.
+- Model-level tests using SQLite in-memory engine.
+
 ## 2026-05-28 — Authentication: scaffold
 
 ### Added