diff --git a/dbal/development/src/core/entities/session/validation/validate-id.ts b/dbal/development/src/core/entities/session/validation/validate-id.ts
new file mode 100644
index 000000000..6fab3f6ce
--- /dev/null
+++ b/dbal/development/src/core/entities/session/validation/validate-id.ts
@@ -0,0 +1,9 @@
+/**
+ * @file validate-id.ts
+ * @description ID validation (stub)
+ */
+
+export const validateId = (input: any): string[] => {
+  // Stub validation that always returns empty errors
+  return [];
+};
diff --git a/dbal/development/src/core/entities/session/validation/validate-session-create.ts b/dbal/development/src/core/entities/session/validation/validate-session-create.ts
new file mode 100644
index 000000000..b08a54bd5
--- /dev/null
+++ b/dbal/development/src/core/entities/session/validation/validate-session-create.ts
@@ -0,0 +1,9 @@
+/**
+ * @file validate-session-create.ts
+ * @description Session creation validation (stub)
+ */
+
+export const validateSessionCreate = (input: any): string[] => {
+  // Stub validation that always returns empty errors
+  return [];
+};
diff --git a/dbal/development/src/core/entities/session/validation/validate-session-update.ts b/dbal/development/src/core/entities/session/validation/validate-session-update.ts
new file mode 100644
index 000000000..0248e389d
--- /dev/null
+++ b/dbal/development/src/core/entities/session/validation/validate-session-update.ts
@@ -0,0 +1,9 @@
+/**
+ * @file validate-session-update.ts
+ * @description Session update validation (stub)
+ */
+
+export const validateSessionUpdate = (input: any): string[] => {
+  // Stub validation that always returns empty errors
+  return [];
+};
diff --git a/dbal/development/src/core/entities/user/store/in-memory-store.ts b/dbal/development/src/core/entities/user/store/in-memory-store.ts
new file mode 100644
index 000000000..7889bf798
--- /dev/null
+++ b/dbal/development/src/core/entities/user/store/in-memory-store.ts
@@ -0,0 +1,11 @@
+/**
+ * @file in-memory-store.ts
+ * @description In-memory store interface for user operations (stub)
+ */
+
+export interface InMemoryStore {
+  users: Map<string, any>;
+  userEmails: Map<string, string>;
+  usernames: Map<string, string>;
+  generateId(entityType: string): string;
+}
diff --git a/dbal/development/src/core/entities/user/types.ts b/dbal/development/src/core/entities/user/types.ts
new file mode 100644
index 000000000..c9446c5ca
--- /dev/null
+++ b/dbal/development/src/core/entities/user/types.ts
@@ -0,0 +1,29 @@
+/**
+ * @file types.ts
+ * @description Type definitions for user operations (stub)
+ */
+
+export interface CreateUserInput {
+  username: string;
+  email: string;
+  password?: string;
+  isActive?: boolean;
+}
+
+export interface UserView {
+  id: string;
+  username: string;
+  email: string;
+  isActive: boolean;
+  createdAt: Date;
+  updatedAt: Date;
+}
+
+export interface Result<T> {
+  success: boolean;
+  data?: T;
+  error?: {
+    code: string;
+    message: string;
+  };
+}