diff --git a/.gitignore b/.gitignore
index 79ac9cf..1c55394 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,6 @@
 */obj/
 */bin/
-.idea
\ No newline at end of file
+.idea
+
+# Postgres data
+data/
diff --git a/Epsilon/Controllers/TestController.cs b/Epsilon/Controllers/TestController.cs
new file mode 100644
index 0000000..d774c69
--- /dev/null
+++ b/Epsilon/Controllers/TestController.cs
@@ -0,0 +1,25 @@
+using Epsilon.Data;
+using Epsilon.Models;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.EntityFrameworkCore;
+
+namespace Epsilon.Controllers;
+
+[ApiController]
+[Route("api")]
+public class TestController
+{
+
+    private readonly EpsilonDbContext _epsilonDbContext;
+
+    public TestController(EpsilonDbContext epsilonDbContext)
+    {
+        _epsilonDbContext = epsilonDbContext;
+    }
+
+    [HttpGet("users")]
+    public async Task<ActionResult<IList<User>>> GetUsers()
+    {
+        return await _epsilonDbContext.Users.ToListAsync();
+    }
+}
\ No newline at end of file
diff --git a/Epsilon/Data/EpsilonDbContext.cs b/Epsilon/Data/EpsilonDbContext.cs
new file mode 100644
index 0000000..ae60474
--- /dev/null
+++ b/Epsilon/Data/EpsilonDbContext.cs
@@ -0,0 +1,14 @@
+using Epsilon.Models;
+using Microsoft.EntityFrameworkCore;
+
+namespace Epsilon.Data;
+
+public class EpsilonDbContext : DbContext
+{
+    public EpsilonDbContext(DbContextOptions<EpsilonDbContext> options) : base(options)
+    {
+    }
+
+    public DbSet<Message> Messages { get; set; }
+    public DbSet<User> Users { get; set; }
+}
\ No newline at end of file
diff --git a/Epsilon/DatabaseInitializer.cs b/Epsilon/DatabaseInitializer.cs
new file mode 100644
index 0000000..53c72e7
--- /dev/null
+++ b/Epsilon/DatabaseInitializer.cs
@@ -0,0 +1,77 @@
+using System.Runtime.InteropServices.JavaScript;
+using Epsilon.Data;
+using Epsilon.Models;
+using Microsoft.EntityFrameworkCore;
+
+namespace Epsilon;
+public class DatabaseInitializer
+{
+    public static void Seed(WebApplication app)
+    {
+        using (var serviceScope = app.Services.CreateScope())
+        {
+            var context = serviceScope.ServiceProvider.GetService<EpsilonDbContext>();
+
+            if (context != null)
+            {
+                if (!context.Users.Any())
+                    InitUsers(context);
+
+                if (!context.Messages.Any())
+                    InitMessages(context);
+            }
+        }
+
+    }
+
+    public static void Migrate(WebApplication app)
+    {
+        // Migrate db
+        using (var scope = app.Services.CreateScope())
+        {
+            var db = scope.ServiceProvider.GetRequiredService<EpsilonDbContext>();
+            db.Database.Migrate();
+        }
+    }
+
+    private static byte[] GenerateRandomBytes(int length)
+    {
+        byte[] randomBytes = new byte[length];
+        Random random = new Random();
+
+        random.NextBytes(randomBytes);
+
+        return randomBytes;
+    }
+
+    private static void InitUsers(EpsilonDbContext context)
+    {
+        var usersToAdd = new List<User>
+        {
+            new User { Id = GenerateRandomBytes(32), PublicKey = GenerateRandomBytes(256), Username = "user_1"},
+            new User { Id = GenerateRandomBytes(32), PublicKey = GenerateRandomBytes(256), Username = "user_2"},
+            new User { Id = GenerateRandomBytes(32), PublicKey = GenerateRandomBytes(256), Username = "user_3"},
+            new User { Id = GenerateRandomBytes(32), PublicKey = GenerateRandomBytes(256), Username = "user_4"},
+        };
+        foreach (var user in usersToAdd)
+            context.Users.Add(user);
+
+        context.SaveChanges();
+    }
+
+    private static void InitMessages(EpsilonDbContext context)
+    {
+        var messagesToAdd = new List<Message>
+        {
+            new Message { EncryptedMessage  = GenerateRandomBytes(256), SenderId = GenerateRandomBytes(32), RecipientId = GenerateRandomBytes(32), CreatedAt = new DateTime() },
+            new Message { EncryptedMessage  = GenerateRandomBytes(256), SenderId = GenerateRandomBytes(32), RecipientId = GenerateRandomBytes(32), CreatedAt = new DateTime() },
+            new Message { EncryptedMessage  = GenerateRandomBytes(256), SenderId = GenerateRandomBytes(32), RecipientId = GenerateRandomBytes(32), CreatedAt = new DateTime() },
+            new Message { EncryptedMessage  = GenerateRandomBytes(256), SenderId = GenerateRandomBytes(32), RecipientId = GenerateRandomBytes(32), CreatedAt = new DateTime() }
+        };
+
+        foreach (var message in messagesToAdd)
+            context.Messages.Add(message);
+
+        context.SaveChanges();
+    }
+}
\ No newline at end of file
diff --git a/Epsilon/Epsilon.csproj b/Epsilon/Epsilon.csproj
index 6158569..6558900 100644
--- a/Epsilon/Epsilon.csproj
+++ b/Epsilon/Epsilon.csproj
@@ -8,7 +8,9 @@
   </PropertyGroup>
 
   <ItemGroup>
+    <PackageReference Include="Microsoft.EntityFrameworkCore" Version="8.0.6" />
     <PackageReference Include="Newtonsoft.Json" Version="13.0.3" />
+    <PackageReference Include="Npgsql.EntityFrameworkCore.PostgreSQL" Version="8.0.4" />
     <PackageReference Include="Serilog.AspNetCore" Version="8.0.2-dev-00338" />
     <PackageReference Include="Serilog.Enrichers.Environment" Version="3.0.1" />
     <PackageReference Include="Serilog.Exceptions" Version="8.4.0" />
diff --git a/Epsilon/IMessageManager.cs b/Epsilon/IMessageManager.cs
new file mode 100644
index 0000000..98f97c1
--- /dev/null
+++ b/Epsilon/IMessageManager.cs
@@ -0,0 +1,12 @@
+using Epsilon.Models;
+
+namespace Epsilon;
+
+public interface IMessageManager
+{
+    public Task AddMessage(Message message);
+    public Task DeleteMessage(byte[] messageId);
+    public Task<List<Message>> GetAllMessages();
+    public Task<List<Message>> GetMessagesBetweenUsers(byte[] userId1, byte[] userId2, DateTime? startDate = null, DateTime? endDate = null);
+    public Task<Message> GetMessageById(byte[] messageId);
+}
\ No newline at end of file
diff --git a/Epsilon/IUserManager.cs b/Epsilon/IUserManager.cs
new file mode 100644
index 0000000..22e7b46
--- /dev/null
+++ b/Epsilon/IUserManager.cs
@@ -0,0 +1,11 @@
+using Epsilon.Models;
+
+namespace Epsilon;
+
+public interface IUserManager
+{
+    Task AddUser(User user);
+    Task DeleteUser(byte[] userId);
+    Task<List<User>> GetAllUsers();
+    Task<User> GetUserById(byte[] userId);
+}
\ No newline at end of file
diff --git a/Epsilon/MessageManager.cs b/Epsilon/MessageManager.cs
new file mode 100644
index 0000000..6012576
--- /dev/null
+++ b/Epsilon/MessageManager.cs
@@ -0,0 +1,32 @@
+using Epsilon.Models;
+
+namespace Epsilon;
+
+public class MessageManager : IMessageManager
+{
+    public Task AddMessage(Message message)
+    {
+        throw new NotImplementedException();
+    }
+
+    public Task DeleteMessage(byte[] messageId)
+    {
+        throw new NotImplementedException();
+    }
+
+    public Task<List<Message>> GetAllMessages()
+    {
+        throw new NotImplementedException();
+    }
+
+    public Task<List<Message>> GetMessagesBetweenUsers(byte[] userId1, byte[] userId2, DateTime? startDate = null,
+        DateTime? endDate = null)
+    {
+        throw new NotImplementedException();
+    }
+
+    public Task<Message> GetMessageById(byte[] messageId)
+    {
+        throw new NotImplementedException();
+    }
+}
\ No newline at end of file
diff --git a/Epsilon/Migrations/20240625191035_InitialCreate.Designer.cs b/Epsilon/Migrations/20240625191035_InitialCreate.Designer.cs
new file mode 100644
index 0000000..5530823
--- /dev/null
+++ b/Epsilon/Migrations/20240625191035_InitialCreate.Designer.cs
@@ -0,0 +1,78 @@
+// <auto-generated />
+using System;
+using Epsilon.Data;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
+
+#nullable disable
+
+namespace Epsilon.Migrations
+{
+    [DbContext(typeof(EpsilonDbContext))]
+    [Migration("20240625191035_InitialCreate")]
+    partial class InitialCreate
+    {
+        /// <inheritdoc />
+        protected override void BuildTargetModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .HasAnnotation("ProductVersion", "8.0.6")
+                .HasAnnotation("Relational:MaxIdentifierLength", 63);
+
+            NpgsqlModelBuilderExtensions.UseIdentityByDefaultColumns(modelBuilder);
+
+            modelBuilder.Entity("Epsilon.Models.Message", b =>
+                {
+                    b.Property<int?>("MessageId")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("integer");
+
+                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int?>("MessageId"));
+
+                    b.Property<DateTime?>("CreatedAt")
+                        .IsRequired()
+                        .HasColumnType("timestamp with time zone");
+
+                    b.Property<byte[]>("EncryptedMessage")
+                        .IsRequired()
+                        .HasColumnType("bytea");
+
+                    b.Property<byte[]>("RecipientId")
+                        .IsRequired()
+                        .HasColumnType("bytea");
+
+                    b.Property<byte[]>("SenderId")
+                        .IsRequired()
+                        .HasColumnType("bytea");
+
+                    b.HasKey("MessageId");
+
+                    b.ToTable("Messages");
+                });
+
+            modelBuilder.Entity("Epsilon.Models.User", b =>
+                {
+                    b.Property<byte[]>("Id")
+                        .HasColumnType("bytea");
+
+                    b.Property<byte[]>("PublicKey")
+                        .IsRequired()
+                        .HasColumnType("bytea");
+
+                    b.Property<string>("Username")
+                        .IsRequired()
+                        .HasMaxLength(16)
+                        .HasColumnType("character varying(16)");
+
+                    b.HasKey("Id");
+
+                    b.ToTable("Users");
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}
diff --git a/Epsilon/Migrations/20240625191035_InitialCreate.cs b/Epsilon/Migrations/20240625191035_InitialCreate.cs
new file mode 100644
index 0000000..f2ff5eb
--- /dev/null
+++ b/Epsilon/Migrations/20240625191035_InitialCreate.cs
@@ -0,0 +1,55 @@
+using System;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
+
+#nullable disable
+
+namespace Epsilon.Migrations
+{
+    /// <inheritdoc />
+    public partial class InitialCreate : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.CreateTable(
+                name: "Messages",
+                columns: table => new
+                {
+                    MessageId = table.Column<int>(type: "integer", nullable: false)
+                        .Annotation("Npgsql:ValueGenerationStrategy", NpgsqlValueGenerationStrategy.IdentityByDefaultColumn),
+                    SenderId = table.Column<byte[]>(type: "bytea", nullable: false),
+                    RecipientId = table.Column<byte[]>(type: "bytea", nullable: false),
+                    EncryptedMessage = table.Column<byte[]>(type: "bytea", nullable: false),
+                    CreatedAt = table.Column<DateTime>(type: "timestamp with time zone", nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_Messages", x => x.MessageId);
+                });
+
+            migrationBuilder.CreateTable(
+                name: "Users",
+                columns: table => new
+                {
+                    Id = table.Column<byte[]>(type: "bytea", nullable: false),
+                    PublicKey = table.Column<byte[]>(type: "bytea", nullable: false),
+                    Username = table.Column<string>(type: "character varying(16)", maxLength: 16, nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_Users", x => x.Id);
+                });
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropTable(
+                name: "Messages");
+
+            migrationBuilder.DropTable(
+                name: "Users");
+        }
+    }
+}
diff --git a/Epsilon/Migrations/EpsilonDbContextModelSnapshot.cs b/Epsilon/Migrations/EpsilonDbContextModelSnapshot.cs
new file mode 100644
index 0000000..f762a05
--- /dev/null
+++ b/Epsilon/Migrations/EpsilonDbContextModelSnapshot.cs
@@ -0,0 +1,75 @@
+// <auto-generated />
+using System;
+using Epsilon.Data;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
+
+#nullable disable
+
+namespace Epsilon.Migrations
+{
+    [DbContext(typeof(EpsilonDbContext))]
+    partial class EpsilonDbContextModelSnapshot : ModelSnapshot
+    {
+        protected override void BuildModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .HasAnnotation("ProductVersion", "8.0.6")
+                .HasAnnotation("Relational:MaxIdentifierLength", 63);
+
+            NpgsqlModelBuilderExtensions.UseIdentityByDefaultColumns(modelBuilder);
+
+            modelBuilder.Entity("Epsilon.Models.Message", b =>
+                {
+                    b.Property<int?>("MessageId")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("integer");
+
+                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int?>("MessageId"));
+
+                    b.Property<DateTime?>("CreatedAt")
+                        .IsRequired()
+                        .HasColumnType("timestamp with time zone");
+
+                    b.Property<byte[]>("EncryptedMessage")
+                        .IsRequired()
+                        .HasColumnType("bytea");
+
+                    b.Property<byte[]>("RecipientId")
+                        .IsRequired()
+                        .HasColumnType("bytea");
+
+                    b.Property<byte[]>("SenderId")
+                        .IsRequired()
+                        .HasColumnType("bytea");
+
+                    b.HasKey("MessageId");
+
+                    b.ToTable("Messages");
+                });
+
+            modelBuilder.Entity("Epsilon.Models.User", b =>
+                {
+                    b.Property<byte[]>("Id")
+                        .HasColumnType("bytea");
+
+                    b.Property<byte[]>("PublicKey")
+                        .IsRequired()
+                        .HasColumnType("bytea");
+
+                    b.Property<string>("Username")
+                        .IsRequired()
+                        .HasMaxLength(16)
+                        .HasColumnType("character varying(16)");
+
+                    b.HasKey("Id");
+
+                    b.ToTable("Users");
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}
diff --git a/Epsilon/Models/Message.cs b/Epsilon/Models/Message.cs
new file mode 100644
index 0000000..e128429
--- /dev/null
+++ b/Epsilon/Models/Message.cs
@@ -0,0 +1,25 @@
+using System.ComponentModel.DataAnnotations;
+using System.ComponentModel.DataAnnotations.Schema;
+
+namespace Epsilon.Models;
+public class Message
+{
+    [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
+    public int? MessageId { get; set; }
+
+    // Hash of senders's public key
+    [Required]
+    [ForeignKey("User")]
+    public byte[]? SenderId { get; set; }
+
+    // Hash of recipient's public key
+    [Required]
+    [ForeignKey("User")]
+    public byte[]? RecipientId { get; set; }
+
+    [Required]
+    public byte[]? EncryptedMessage { get; set; }
+
+    [Required]
+    public DateTime? CreatedAt { get; set; }
+}
\ No newline at end of file
diff --git a/Epsilon/Models/User.cs b/Epsilon/Models/User.cs
new file mode 100644
index 0000000..a890af3
--- /dev/null
+++ b/Epsilon/Models/User.cs
@@ -0,0 +1,17 @@
+using System.ComponentModel.DataAnnotations;
+
+namespace Epsilon.Models;
+public class User
+{
+    // Hash of user's public key
+    [Key]
+    public byte[]? Id { get; set; }
+
+    [Required]
+    public byte[]? PublicKey { get; set; }
+
+    // Can we possibly encrypt this such that only the sender and receiver can view this?
+    [Required]
+    [StringLength(16)]
+    public string? Username { get; set; }
+}
\ No newline at end of file
diff --git a/Epsilon/Program.cs b/Epsilon/Program.cs
index 50742c2..a633c88 100644
--- a/Epsilon/Program.cs
+++ b/Epsilon/Program.cs
@@ -1,4 +1,6 @@
 using Epsilon;
+using Epsilon.Data;
+using Microsoft.EntityFrameworkCore;
 using Epsilon.Handler.WebsocketMessageHandler;
 using Epsilon.Models;
 using Epsilon.Services.WebsocketStateService;
@@ -14,6 +16,11 @@
 
 builder.Services.AddHealthChecks();
 builder.Services.AddControllers();
+builder.Services.AddTransient<IUserManager, UserManager>();
+builder.Services.AddTransient<IMessageManager, MessageManager>();
+builder.Services.AddDbContext<EpsilonDbContext>(options =>
+    options.UseNpgsql(builder.Configuration.GetConnectionString("DefaultConnection"))
+);
 builder.Services.AddTransient<IMessageHandler<string>, WebsocketMessageHandler>();
 builder.Services.AddTransient<IMessageHandler<LoginRequest>, LoginRequestMessageHandler>();
 builder.Services.AddTransient<IMessageHandler<MessageRequest>, MessageRequestMessageHandler>();
@@ -31,4 +38,10 @@
     KeepAliveInterval = TimeSpan.FromSeconds(30),
 });
 
+// Migrate db
+DatabaseInitializer.Migrate(app);
+
+// Seed database
+DatabaseInitializer.Seed(app);
+
 await app.RunAsync();
\ No newline at end of file
diff --git a/Epsilon/UserManager.cs b/Epsilon/UserManager.cs
new file mode 100644
index 0000000..a3765ac
--- /dev/null
+++ b/Epsilon/UserManager.cs
@@ -0,0 +1,26 @@
+using Epsilon.Models;
+
+namespace Epsilon;
+
+public class UserManager : IUserManager
+{
+    public Task AddUser(User user)
+    {
+        throw new NotImplementedException();
+    }
+
+    public Task DeleteUser(byte[] userId)
+    {
+        throw new NotImplementedException();
+    }
+
+    public Task<List<User>> GetAllUsers()
+    {
+        throw new NotImplementedException();
+    }
+
+    public Task<User> GetUserById(byte[] userId)
+    {
+        throw new NotImplementedException();
+    }
+}
\ No newline at end of file
diff --git a/Epsilon/appsettings.Development.json b/Epsilon/appsettings.Development.json
index 8b34174..f6e643d 100644
--- a/Epsilon/appsettings.Development.json
+++ b/Epsilon/appsettings.Development.json
@@ -3,5 +3,8 @@
     "MinimumLevel": {
       "Default": "Debug"
     }
+  },
+  "ConnectionStrings": {
+    "DefaultConnection": "Host=localhost;Port=5432;Database=EpsilonDB;Username=root;Password=password"
   }
 }
\ No newline at end of file
diff --git a/Epsilon/appsettings.IntegrationTest.json b/Epsilon/appsettings.IntegrationTest.json
index 8b34174..aa30b93 100644
--- a/Epsilon/appsettings.IntegrationTest.json
+++ b/Epsilon/appsettings.IntegrationTest.json
@@ -3,5 +3,8 @@
     "MinimumLevel": {
       "Default": "Debug"
     }
+  },
+  "ConnectionStrings": {
+    "DefaultConnection": "Host=postgres;Port=5432;Database=EpsilonDB;Username=root;Password=password"
   }
 }
\ No newline at end of file
diff --git a/IntegrationTests/PostgresTests.cs b/IntegrationTests/PostgresTests.cs
new file mode 100644
index 0000000..a625a23
--- /dev/null
+++ b/IntegrationTests/PostgresTests.cs
@@ -0,0 +1,24 @@
+using System.Net;
+using Epsilon.Models;
+using FluentAssertions;
+using Newtonsoft.Json;
+using Xunit;
+
+namespace IntegrationTests;
+
+public class PostgresTests
+{
+    private readonly HttpClient _client = new();
+
+    [Fact]
+    public async Task Epsilon_ShouldReturnListOfUsers()
+    {
+        var response = await _client.GetAsync("http://localhost:5172/api/users");
+
+        response.StatusCode.Should().Be(HttpStatusCode.OK);
+
+        var body = await response.Content.ReadAsStringAsync();
+        var users = JsonConvert.DeserializeObject<List<User>>(body)!;
+        users.Should().HaveCount(4);
+    }
+}
\ No newline at end of file
diff --git a/Makefile b/Makefile
index 20d9343..f73a888 100644
--- a/Makefile
+++ b/Makefile
@@ -23,6 +23,9 @@ down:
 	echo "Down"
 	docker-compose -f docker-compose-test.yml down
 	
+services:
+	docker-compose -f docker-compose-postgres.yml up
+	
 send_logs:
 	.buildkite/scripts/docker-logs.sh
 	make down
diff --git a/docker-compose-postgres.yml b/docker-compose-postgres.yml
new file mode 100644
index 0000000..589ce4a
--- /dev/null
+++ b/docker-compose-postgres.yml
@@ -0,0 +1,12 @@
+services:
+  dbPostgres:
+    image: postgres
+    restart: always
+    environment:
+      POSTGRES_USER: root
+      POSTGRES_PASSWORD: password
+      POSTGRES_DB: EpsilonDB
+    ports:
+      - 5432:5432
+    volumes:
+      - ./data:/var/lib/postgresql/data
\ No newline at end of file
diff --git a/docker-compose-test.yml b/docker-compose-test.yml
index 015652a..549e1d8 100644
--- a/docker-compose-test.yml
+++ b/docker-compose-test.yml
@@ -4,7 +4,7 @@ services:
     entrypoint: /bin/bash
     working_dir: "/app"
     depends_on:
-      epsilon: 
+      epsilon:
         condition: service_healthy
     volumes:
       - "./:/app:rw"
@@ -14,6 +14,8 @@ services:
     image: mcr.microsoft.com/dotnet/sdk:8.0
     entrypoint: /bin/bash
     working_dir: "/app"
+    depends_on:
+      - postgres
     volumes:
       - "./:/app:rw"
     command: ".buildkite/scripts/run.sh Epsilon"
@@ -21,4 +23,12 @@ services:
       test: curl --fail -k http://localhost:5172/health || exit 1
       interval: 10s
       timeout: 5s
-      retries: 5
\ No newline at end of file
+      retries: 5
+  
+  postgres:
+    image: postgres
+    restart: always
+    environment:
+      POSTGRES_USER: root
+      POSTGRES_PASSWORD: password
+      POSTGRES_DB: EpsilonDB
\ No newline at end of file