diff --git a/src/FiscalOS.Core/Data/Entity.cs b/src/FiscalOS.Core/Data/Entity.cs
new file mode 100644
index 0000000..8b5f7f9
--- /dev/null
+++ b/src/FiscalOS.Core/Data/Entity.cs
@@ -0,0 +1,18 @@
+namespace FiscalOS.Core.Data;
+
+public abstract class Entity
+{
+  public Guid Id { get; init; }
+  public DateTimeOffset CreatedAt { get; private set; }
+  public DateTimeOffset UpdatedAt { get; private set; }
+
+  public void SetCreatedAt(DateTimeOffset createdAt)
+  {
+    CreatedAt = createdAt;
+  }
+
+  public void SetUpdatedAt(DateTimeOffset updatedAt)
+  {
+    UpdatedAt = updatedAt;
+  }
+}
\ No newline at end of file
diff --git a/src/FiscalOS.Core/Identity/IPasswordHasher.cs b/src/FiscalOS.Core/Identity/IPasswordHasher.cs
new file mode 100644
index 0000000..280ab67
--- /dev/null
+++ b/src/FiscalOS.Core/Identity/IPasswordHasher.cs
@@ -0,0 +1,7 @@
+namespace FiscalOS.Core.Identity;
+
+public interface IPasswordHasher
+{
+  string Hash(string password);
+  bool Verify(string providedPassword, string hashedPassword);
+}
\ No newline at end of file
diff --git a/src/FiscalOS.Core/Usings.cs b/src/FiscalOS.Core/Usings.cs
new file mode 100644
index 0000000..c70d0ad
--- /dev/null
+++ b/src/FiscalOS.Core/Usings.cs
@@ -0,0 +1 @@
+global using FiscalOS.Core.Data;
\ No newline at end of file