diff --git a/ProjectLighthouse.Tests/Tests/DatabaseTests.cs b/ProjectLighthouse.Tests/Tests/DatabaseTests.cs
new file mode 100644
index 00000000..113e2a63
--- /dev/null
+++ b/ProjectLighthouse.Tests/Tests/DatabaseTests.cs
@@ -0,0 +1,15 @@
+using System;
+using System.Threading.Tasks;
+
+namespace ProjectLighthouse.Tests {
+    public class DatabaseTests : LighthouseTest {
+        [DatabaseFact]
+        public async Task CanCreateUserTwice() {
+            await using Database database = new();
+            int rand = new Random().Next();
+
+            await database.CreateUser("createUserTwiceTest" + rand);
+            await database.CreateUser("createUserTwiceTest" + rand);
+        }
+    }
+}
\ No newline at end of file
diff --git a/ProjectLighthouse.Tests/Tests/SlotTests.cs b/ProjectLighthouse.Tests/Tests/SlotTests.cs
new file mode 100644
index 00000000..63933093
--- /dev/null
+++ b/ProjectLighthouse.Tests/Tests/SlotTests.cs
@@ -0,0 +1,50 @@
+using System.Collections.Generic;
+using System.Net.Http;
+using System.Threading.Tasks;
+using ProjectLighthouse.Types;
+using Xunit;
+
+namespace ProjectLighthouse.Tests {
+    public class SlotTests : LighthouseTest {
+        [DatabaseFact]
+        public async Task ShouldOnlyShowUsersLevels() {
+            await using Database database = new();
+
+            User userA = await database.CreateUser("unitTestUser0");
+            User userB = await database.CreateUser("unitTestUser1");
+
+            Location l = new();
+            database.Locations.Add(l);
+            await database.SaveChangesAsync();
+
+            Slot slotA = new() {
+                Creator = userA,
+                Name = "slotA",
+                Location = l,
+                LocationId = l.Id,
+            };
+
+            Slot slotB = new() {
+                Creator = userB,
+                Name = "slotB",
+                Location = l,
+                LocationId = l.Id,
+            };
+
+            database.Slots.Add(slotA);
+            database.Slots.Add(slotB);
+
+            await database.SaveChangesAsync();
+
+//            XmlSerializer serializer = new(typeof(Slot));
+//            Slot slot = (Slot)serializer.Deserialize(new StringReader(bodyString));
+
+            string respA = await this.Client.GetStringAsync("LITTLEBIGPLANETPS3_XML/slots/by?u=unitTestUser0");
+            string respB = await this.Client.GetStringAsync("LITTLEBIGPLANETPS3_XML/slots/by?u=unitTestUser1");
+
+            Assert.NotEqual(respA, respB);
+            Assert.DoesNotContain(respA, "slotB");
+            Assert.DoesNotContain(respB, "slotA");
+        }
+    }
+}
\ No newline at end of file
diff --git a/ProjectLighthouse/Database.cs b/ProjectLighthouse/Database.cs
index 8700e32a..0cd18e70 100644
--- a/ProjectLighthouse/Database.cs
+++ b/ProjectLighthouse/Database.cs
@@ -1,3 +1,4 @@
+using System.Linq;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Http;
 using Microsoft.EntityFrameworkCore;
@@ -22,11 +23,15 @@ namespace ProjectLighthouse {
         );
 
         public async Task<User> CreateUser(string username) {
+            User user;
+            if((user = await Users.Where(u => u.Username == username).FirstOrDefaultAsync()) != null)
+                return user;
+
             Location l = new(); // store to get id after submitting
             this.Locations.Add(l); // add to table
             await this.SaveChangesAsync(); // saving to the database returns the id and sets it on this entity
 
-            User user = new() {
+            user = new() {
                 Username = username,
                 LocationId = l.Id,
                 Biography = username + " hasn't introduced themselves yet.",
@@ -36,7 +41,6 @@ namespace ProjectLighthouse {
             await this.SaveChangesAsync();
 
             return user;
-
         }
         
         #nullable enable