diff --git a/backend/Data/AppDbContext.cs b/backend/Data/AppDbContext.cs
index 3698a23..a73683e 100644
--- a/backend/Data/AppDbContext.cs
+++ b/backend/Data/AppDbContext.cs
@@ -1,4 +1,6 @@
 using backend.Auth;
+using backend.Devices;
+using backend.Settings;
 using Microsoft.AspNetCore.Identity;
 using Microsoft.AspNetCore.Identity.EntityFrameworkCore;
 using Microsoft.EntityFrameworkCore;
@@ -8,4 +10,22 @@ namespace backend.Data;
 public class AppDbContext(DbContextOptions<AppDbContext> options)
     : IdentityDbContext<ApplicationUser, IdentityRole<Guid>, Guid>(options)
 {
+    public DbSet<Device> Devices => Set<Device>();
+    public DbSet<DeviceConfig> DeviceConfigs => Set<DeviceConfig>();
+    public DbSet<SystemSettings> SystemSettings => Set<SystemSettings>();
+
+    protected override void OnModelCreating(ModelBuilder b)
+    {
+        base.OnModelCreating(b);
+
+        b.Entity<Device>().HasIndex(d => d.OwnerUserId);
+        b.Entity<Device>().HasIndex(d => d.TokenHash).IsUnique();
+        b.Entity<Device>()
+            .HasOne(d => d.Config)
+            .WithOne()
+            .HasForeignKey<DeviceConfig>(c => c.DeviceId)
+            .OnDelete(DeleteBehavior.Cascade);
+        b.Entity<DeviceConfig>().HasKey(c => c.DeviceId);
+        b.Entity<SystemSettings>().HasKey(s => s.Id);
+    }
 }
diff --git a/backend/Devices/Device.cs b/backend/Devices/Device.cs
new file mode 100644
index 0000000..3158ade
--- /dev/null
+++ b/backend/Devices/Device.cs
@@ -0,0 +1,13 @@
+namespace backend.Devices;
+
+public class Device
+{
+    public Guid Id { get; set; } = Guid.NewGuid();
+    public Guid OwnerUserId { get; set; }
+    public string Name { get; set; } = "";
+    public DateTimeOffset PairedAt { get; set; }
+    public DateTimeOffset? LastSeenAt { get; set; }
+    public string TokenHash { get; set; } = "";
+    public bool IsRevoked { get; set; }
+    public DeviceConfig? Config { get; set; }
+}
diff --git a/backend/Devices/DeviceConfig.cs b/backend/Devices/DeviceConfig.cs
new file mode 100644
index 0000000..c56baaa
--- /dev/null
+++ b/backend/Devices/DeviceConfig.cs
@@ -0,0 +1,11 @@
+namespace backend.Devices;
+
+public class DeviceConfig
+{
+    public Guid DeviceId { get; set; }
+    public string SystemPrompt { get; set; } = "";
+    public string Voice { get; set; } = "";
+    public string Model { get; set; } = "";
+    public int IdleTimeoutSeconds { get; set; } = 30;
+    public string EnabledToolsJson { get; set; } = "[\"end_session\",\"get_current_time\",\"set_volume\"]";
+}
diff --git a/backend/Migrations/20260611184053_AddDevicesAndSettings.Designer.cs b/backend/Migrations/20260611184053_AddDevicesAndSettings.Designer.cs
new file mode 100644
index 0000000..9ddc0cd
--- /dev/null
+++ b/backend/Migrations/20260611184053_AddDevicesAndSettings.Designer.cs
@@ -0,0 +1,372 @@
+// <auto-generated />
+using System;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using backend.Data;
+
+#nullable disable
+
+namespace backend.Migrations
+{
+    [DbContext(typeof(AppDbContext))]
+    [Migration("20260611184053_AddDevicesAndSettings")]
+    partial class AddDevicesAndSettings
+    {
+        /// <inheritdoc />
+        protected override void BuildTargetModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder.HasAnnotation("ProductVersion", "9.0.17");
+
+            modelBuilder.Entity("Microsoft.AspNetCore.Identity.IdentityRole<System.Guid>", b =>
+                {
+                    b.Property<Guid>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("ConcurrencyStamp")
+                        .IsConcurrencyToken()
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("Name")
+                        .HasMaxLength(256)
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("NormalizedName")
+                        .HasMaxLength(256)
+                        .HasColumnType("TEXT");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("NormalizedName")
+                        .IsUnique()
+                        .HasDatabaseName("RoleNameIndex");
+
+                    b.ToTable("AspNetRoles", (string)null);
+                });
+
+            modelBuilder.Entity("Microsoft.AspNetCore.Identity.IdentityRoleClaim<System.Guid>", b =>
+                {
+                    b.Property<int>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("INTEGER");
+
+                    b.Property<string>("ClaimType")
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("ClaimValue")
+                        .HasColumnType("TEXT");
+
+                    b.Property<Guid>("RoleId")
+                        .HasColumnType("TEXT");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("RoleId");
+
+                    b.ToTable("AspNetRoleClaims", (string)null);
+                });
+
+            modelBuilder.Entity("Microsoft.AspNetCore.Identity.IdentityUserClaim<System.Guid>", b =>
+                {
+                    b.Property<int>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("INTEGER");
+
+                    b.Property<string>("ClaimType")
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("ClaimValue")
+                        .HasColumnType("TEXT");
+
+                    b.Property<Guid>("UserId")
+                        .HasColumnType("TEXT");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("UserId");
+
+                    b.ToTable("AspNetUserClaims", (string)null);
+                });
+
+            modelBuilder.Entity("Microsoft.AspNetCore.Identity.IdentityUserLogin<System.Guid>", b =>
+                {
+                    b.Property<string>("LoginProvider")
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("ProviderKey")
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("ProviderDisplayName")
+                        .HasColumnType("TEXT");
+
+                    b.Property<Guid>("UserId")
+                        .HasColumnType("TEXT");
+
+                    b.HasKey("LoginProvider", "ProviderKey");
+
+                    b.HasIndex("UserId");
+
+                    b.ToTable("AspNetUserLogins", (string)null);
+                });
+
+            modelBuilder.Entity("Microsoft.AspNetCore.Identity.IdentityUserRole<System.Guid>", b =>
+                {
+                    b.Property<Guid>("UserId")
+                        .HasColumnType("TEXT");
+
+                    b.Property<Guid>("RoleId")
+                        .HasColumnType("TEXT");
+
+                    b.HasKey("UserId", "RoleId");
+
+                    b.HasIndex("RoleId");
+
+                    b.ToTable("AspNetUserRoles", (string)null);
+                });
+
+            modelBuilder.Entity("Microsoft.AspNetCore.Identity.IdentityUserToken<System.Guid>", b =>
+                {
+                    b.Property<Guid>("UserId")
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("LoginProvider")
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("Name")
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("Value")
+                        .HasColumnType("TEXT");
+
+                    b.HasKey("UserId", "LoginProvider", "Name");
+
+                    b.ToTable("AspNetUserTokens", (string)null);
+                });
+
+            modelBuilder.Entity("backend.Auth.ApplicationUser", b =>
+                {
+                    b.Property<Guid>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("TEXT");
+
+                    b.Property<int>("AccessFailedCount")
+                        .HasColumnType("INTEGER");
+
+                    b.Property<string>("ConcurrencyStamp")
+                        .IsConcurrencyToken()
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("Email")
+                        .HasMaxLength(256)
+                        .HasColumnType("TEXT");
+
+                    b.Property<bool>("EmailConfirmed")
+                        .HasColumnType("INTEGER");
+
+                    b.Property<bool>("LockoutEnabled")
+                        .HasColumnType("INTEGER");
+
+                    b.Property<DateTimeOffset?>("LockoutEnd")
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("NormalizedEmail")
+                        .HasMaxLength(256)
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("NormalizedUserName")
+                        .HasMaxLength(256)
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("PasswordHash")
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("PhoneNumber")
+                        .HasColumnType("TEXT");
+
+                    b.Property<bool>("PhoneNumberConfirmed")
+                        .HasColumnType("INTEGER");
+
+                    b.Property<string>("SecurityStamp")
+                        .HasColumnType("TEXT");
+
+                    b.Property<bool>("TwoFactorEnabled")
+                        .HasColumnType("INTEGER");
+
+                    b.Property<string>("UserName")
+                        .HasMaxLength(256)
+                        .HasColumnType("TEXT");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("NormalizedEmail")
+                        .HasDatabaseName("EmailIndex");
+
+                    b.HasIndex("NormalizedUserName")
+                        .IsUnique()
+                        .HasDatabaseName("UserNameIndex");
+
+                    b.ToTable("AspNetUsers", (string)null);
+                });
+
+            modelBuilder.Entity("backend.Devices.Device", b =>
+                {
+                    b.Property<Guid>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("TEXT");
+
+                    b.Property<bool>("IsRevoked")
+                        .HasColumnType("INTEGER");
+
+                    b.Property<DateTimeOffset?>("LastSeenAt")
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("Name")
+                        .IsRequired()
+                        .HasColumnType("TEXT");
+
+                    b.Property<Guid>("OwnerUserId")
+                        .HasColumnType("TEXT");
+
+                    b.Property<DateTimeOffset>("PairedAt")
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("TokenHash")
+                        .IsRequired()
+                        .HasColumnType("TEXT");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("OwnerUserId");
+
+                    b.HasIndex("TokenHash")
+                        .IsUnique();
+
+                    b.ToTable("Devices");
+                });
+
+            modelBuilder.Entity("backend.Devices.DeviceConfig", b =>
+                {
+                    b.Property<Guid>("DeviceId")
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("EnabledToolsJson")
+                        .IsRequired()
+                        .HasColumnType("TEXT");
+
+                    b.Property<int>("IdleTimeoutSeconds")
+                        .HasColumnType("INTEGER");
+
+                    b.Property<string>("Model")
+                        .IsRequired()
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("SystemPrompt")
+                        .IsRequired()
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("Voice")
+                        .IsRequired()
+                        .HasColumnType("TEXT");
+
+                    b.HasKey("DeviceId");
+
+                    b.ToTable("DeviceConfigs");
+                });
+
+            modelBuilder.Entity("backend.Settings.SystemSettings", b =>
+                {
+                    b.Property<int>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("INTEGER");
+
+                    b.Property<int>("DefaultIdleTimeoutSeconds")
+                        .HasColumnType("INTEGER");
+
+                    b.Property<string>("DefaultModel")
+                        .IsRequired()
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("DefaultSystemPrompt")
+                        .IsRequired()
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("DefaultVoice")
+                        .IsRequired()
+                        .HasColumnType("TEXT");
+
+                    b.HasKey("Id");
+
+                    b.ToTable("SystemSettings");
+                });
+
+            modelBuilder.Entity("Microsoft.AspNetCore.Identity.IdentityRoleClaim<System.Guid>", b =>
+                {
+                    b.HasOne("Microsoft.AspNetCore.Identity.IdentityRole<System.Guid>", null)
+                        .WithMany()
+                        .HasForeignKey("RoleId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+                });
+
+            modelBuilder.Entity("Microsoft.AspNetCore.Identity.IdentityUserClaim<System.Guid>", b =>
+                {
+                    b.HasOne("backend.Auth.ApplicationUser", null)
+                        .WithMany()
+                        .HasForeignKey("UserId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+                });
+
+            modelBuilder.Entity("Microsoft.AspNetCore.Identity.IdentityUserLogin<System.Guid>", b =>
+                {
+                    b.HasOne("backend.Auth.ApplicationUser", null)
+                        .WithMany()
+                        .HasForeignKey("UserId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+                });
+
+            modelBuilder.Entity("Microsoft.AspNetCore.Identity.IdentityUserRole<System.Guid>", b =>
+                {
+                    b.HasOne("Microsoft.AspNetCore.Identity.IdentityRole<System.Guid>", null)
+                        .WithMany()
+                        .HasForeignKey("RoleId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+
+                    b.HasOne("backend.Auth.ApplicationUser", null)
+                        .WithMany()
+                        .HasForeignKey("UserId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+                });
+
+            modelBuilder.Entity("Microsoft.AspNetCore.Identity.IdentityUserToken<System.Guid>", b =>
+                {
+                    b.HasOne("backend.Auth.ApplicationUser", null)
+                        .WithMany()
+                        .HasForeignKey("UserId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+                });
+
+            modelBuilder.Entity("backend.Devices.DeviceConfig", b =>
+                {
+                    b.HasOne("backend.Devices.Device", null)
+                        .WithOne("Config")
+                        .HasForeignKey("backend.Devices.DeviceConfig", "DeviceId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+                });
+
+            modelBuilder.Entity("backend.Devices.Device", b =>
+                {
+                    b.Navigation("Config");
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}
diff --git a/backend/Migrations/20260611184053_AddDevicesAndSettings.cs b/backend/Migrations/20260611184053_AddDevicesAndSettings.cs
new file mode 100644
index 0000000..433e4a6
--- /dev/null
+++ b/backend/Migrations/20260611184053_AddDevicesAndSettings.cs
@@ -0,0 +1,94 @@
+using System;
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace backend.Migrations
+{
+    /// <inheritdoc />
+    public partial class AddDevicesAndSettings : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.CreateTable(
+                name: "Devices",
+                columns: table => new
+                {
+                    Id = table.Column<Guid>(type: "TEXT", nullable: false),
+                    OwnerUserId = table.Column<Guid>(type: "TEXT", nullable: false),
+                    Name = table.Column<string>(type: "TEXT", nullable: false),
+                    PairedAt = table.Column<DateTimeOffset>(type: "TEXT", nullable: false),
+                    LastSeenAt = table.Column<DateTimeOffset>(type: "TEXT", nullable: true),
+                    TokenHash = table.Column<string>(type: "TEXT", nullable: false),
+                    IsRevoked = table.Column<bool>(type: "INTEGER", nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_Devices", x => x.Id);
+                });
+
+            migrationBuilder.CreateTable(
+                name: "SystemSettings",
+                columns: table => new
+                {
+                    Id = table.Column<int>(type: "INTEGER", nullable: false)
+                        .Annotation("Sqlite:Autoincrement", true),
+                    DefaultSystemPrompt = table.Column<string>(type: "TEXT", nullable: false),
+                    DefaultVoice = table.Column<string>(type: "TEXT", nullable: false),
+                    DefaultModel = table.Column<string>(type: "TEXT", nullable: false),
+                    DefaultIdleTimeoutSeconds = table.Column<int>(type: "INTEGER", nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_SystemSettings", x => x.Id);
+                });
+
+            migrationBuilder.CreateTable(
+                name: "DeviceConfigs",
+                columns: table => new
+                {
+                    DeviceId = table.Column<Guid>(type: "TEXT", nullable: false),
+                    SystemPrompt = table.Column<string>(type: "TEXT", nullable: false),
+                    Voice = table.Column<string>(type: "TEXT", nullable: false),
+                    Model = table.Column<string>(type: "TEXT", nullable: false),
+                    IdleTimeoutSeconds = table.Column<int>(type: "INTEGER", nullable: false),
+                    EnabledToolsJson = table.Column<string>(type: "TEXT", nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_DeviceConfigs", x => x.DeviceId);
+                    table.ForeignKey(
+                        name: "FK_DeviceConfigs_Devices_DeviceId",
+                        column: x => x.DeviceId,
+                        principalTable: "Devices",
+                        principalColumn: "Id",
+                        onDelete: ReferentialAction.Cascade);
+                });
+
+            migrationBuilder.CreateIndex(
+                name: "IX_Devices_OwnerUserId",
+                table: "Devices",
+                column: "OwnerUserId");
+
+            migrationBuilder.CreateIndex(
+                name: "IX_Devices_TokenHash",
+                table: "Devices",
+                column: "TokenHash",
+                unique: true);
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropTable(
+                name: "DeviceConfigs");
+
+            migrationBuilder.DropTable(
+                name: "SystemSettings");
+
+            migrationBuilder.DropTable(
+                name: "Devices");
+        }
+    }
+}
diff --git a/backend/Migrations/AppDbContextModelSnapshot.cs b/backend/Migrations/AppDbContextModelSnapshot.cs
index 6bc4363..6ce3e2e 100644
--- a/backend/Migrations/AppDbContextModelSnapshot.cs
+++ b/backend/Migrations/AppDbContextModelSnapshot.cs
@@ -208,6 +208,97 @@ namespace backend.Migrations
                     b.ToTable("AspNetUsers", (string)null);
                 });
 
+            modelBuilder.Entity("backend.Devices.Device", b =>
+                {
+                    b.Property<Guid>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("TEXT");
+
+                    b.Property<bool>("IsRevoked")
+                        .HasColumnType("INTEGER");
+
+                    b.Property<DateTimeOffset?>("LastSeenAt")
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("Name")
+                        .IsRequired()
+                        .HasColumnType("TEXT");
+
+                    b.Property<Guid>("OwnerUserId")
+                        .HasColumnType("TEXT");
+
+                    b.Property<DateTimeOffset>("PairedAt")
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("TokenHash")
+                        .IsRequired()
+                        .HasColumnType("TEXT");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("OwnerUserId");
+
+                    b.HasIndex("TokenHash")
+                        .IsUnique();
+
+                    b.ToTable("Devices");
+                });
+
+            modelBuilder.Entity("backend.Devices.DeviceConfig", b =>
+                {
+                    b.Property<Guid>("DeviceId")
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("EnabledToolsJson")
+                        .IsRequired()
+                        .HasColumnType("TEXT");
+
+                    b.Property<int>("IdleTimeoutSeconds")
+                        .HasColumnType("INTEGER");
+
+                    b.Property<string>("Model")
+                        .IsRequired()
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("SystemPrompt")
+                        .IsRequired()
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("Voice")
+                        .IsRequired()
+                        .HasColumnType("TEXT");
+
+                    b.HasKey("DeviceId");
+
+                    b.ToTable("DeviceConfigs");
+                });
+
+            modelBuilder.Entity("backend.Settings.SystemSettings", b =>
+                {
+                    b.Property<int>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("INTEGER");
+
+                    b.Property<int>("DefaultIdleTimeoutSeconds")
+                        .HasColumnType("INTEGER");
+
+                    b.Property<string>("DefaultModel")
+                        .IsRequired()
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("DefaultSystemPrompt")
+                        .IsRequired()
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("DefaultVoice")
+                        .IsRequired()
+                        .HasColumnType("TEXT");
+
+                    b.HasKey("Id");
+
+                    b.ToTable("SystemSettings");
+                });
+
             modelBuilder.Entity("Microsoft.AspNetCore.Identity.IdentityRoleClaim<System.Guid>", b =>
                 {
                     b.HasOne("Microsoft.AspNetCore.Identity.IdentityRole<System.Guid>", null)
@@ -258,6 +349,20 @@ namespace backend.Migrations
                         .OnDelete(DeleteBehavior.Cascade)
                         .IsRequired();
                 });
+
+            modelBuilder.Entity("backend.Devices.DeviceConfig", b =>
+                {
+                    b.HasOne("backend.Devices.Device", null)
+                        .WithOne("Config")
+                        .HasForeignKey("backend.Devices.DeviceConfig", "DeviceId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+                });
+
+            modelBuilder.Entity("backend.Devices.Device", b =>
+                {
+                    b.Navigation("Config");
+                });
 #pragma warning restore 612, 618
         }
     }
diff --git a/backend/Program.cs b/backend/Program.cs
index 3dcfb4e..bf2df6b 100644
--- a/backend/Program.cs
+++ b/backend/Program.cs
@@ -15,8 +15,15 @@ var app = builder.Build();
 using (var scope = app.Services.CreateScope())
 {
     var sp = scope.ServiceProvider;
-    sp.GetRequiredService<AppDbContext>().Database.Migrate();
+    var db = sp.GetRequiredService<AppDbContext>();
+    db.Database.Migrate();
     await IdentitySetup.SeedRolesAsync(sp);
+
+    if (!db.SystemSettings.Any())
+    {
+        db.SystemSettings.Add(new backend.Settings.SystemSettings());
+        await db.SaveChangesAsync();
+    }
 }
 
 app.UseAuthentication();
diff --git a/backend/Settings/SystemSettings.cs b/backend/Settings/SystemSettings.cs
new file mode 100644
index 0000000..650b1de
--- /dev/null
+++ b/backend/Settings/SystemSettings.cs
@@ -0,0 +1,11 @@
+namespace backend.Settings;
+
+public class SystemSettings
+{
+    public int Id { get; set; } = 1;
+    public string DefaultSystemPrompt { get; set; } =
+        "You are a helpful voice assistant. Keep responses concise.";
+    public string DefaultVoice { get; set; } = "alloy";
+    public string DefaultModel { get; set; } = "gpt-4o-realtime-preview";
+    public int DefaultIdleTimeoutSeconds { get; set; } = 30;
+}