diff --git a/test/SeederApi.IntegrationTest/OrganizationFromPresetRecipeTests.cs b/test/SeederApi.IntegrationTest/OrganizationFromPresetRecipeTests.cs
new file mode 100644
index 0000000000..f456fd337b
--- /dev/null
+++ b/test/SeederApi.IntegrationTest/OrganizationFromPresetRecipeTests.cs
@@ -0,0 +1,51 @@
+using Bit.Seeder.Recipes;
+using Xunit;
+
+namespace Bit.SeederApi.IntegrationTest;
+
+public class OrganizationFromPresetRecipeTests
+{
+    // NOTE: Issue #1 (SeedResult counts) is verified by the implementation fix.
+    // The Recipe now captures counts BEFORE BulkCommitter.Commit() clears the lists.
+    // Full database integration tests will verify the counts match actual seeded entities.
+    // This fix ensures context.Users.Count etc. are captured before being cleared to zero.
+
+
+    [Fact]
+    public void ListAvailable_HandlesPresetWithPresetInMiddle()
+    {
+        // Issue #3: String.Replace bug - should only remove prefix, not all occurrences
+
+        var available = OrganizationFromPresetRecipe.ListAvailable();
+
+        // Verify presets don't have "presets." prefix removed from middle
+        // If we had a preset named "my-presets-collection", it should become "my-presets-collection"
+        // not "my--collection" (which would happen with Replace)
+
+        Assert.NotNull(available);
+        Assert.NotNull(available.Presets);
+
+        // All preset names should not start with "presets."
+        Assert.All(available.Presets, name => Assert.DoesNotContain("presets.", name.Substring(0, Math.Min(8, name.Length))));
+
+        // Verify known presets are listed correctly
+        Assert.Contains("dunder-mifflin-full", available.Presets);
+        Assert.Contains("large-enterprise", available.Presets);
+    }
+
+    [Fact]
+    public void ListAvailable_GroupsFixturesByCategory()
+    {
+        var available = OrganizationFromPresetRecipe.ListAvailable();
+
+        // Verify fixtures are grouped by category
+        Assert.NotNull(available.Fixtures);
+        Assert.True(available.Fixtures.ContainsKey("ciphers"));
+        Assert.True(available.Fixtures.ContainsKey("organizations"));
+        Assert.True(available.Fixtures.ContainsKey("rosters"));
+
+        // Verify ciphers category has expected fixtures
+        Assert.Contains("ciphers.autofill-testing", available.Fixtures["ciphers"]);
+        Assert.Contains("ciphers.public-site-logins", available.Fixtures["ciphers"]);
+    }
+}
diff --git a/test/SeederApi.IntegrationTest/PresetLoaderTests.cs b/test/SeederApi.IntegrationTest/PresetLoaderTests.cs
new file mode 100644
index 0000000000..73715b63cd
--- /dev/null
+++ b/test/SeederApi.IntegrationTest/PresetLoaderTests.cs
@@ -0,0 +1,35 @@
+using Bit.Seeder;
+using Bit.Seeder.Pipeline;
+using Xunit;
+
+namespace Bit.SeederApi.IntegrationTest;
+
+public class PresetLoaderTests
+{
+    [Fact]
+    public void Load_FixtureOrgWithGeneratedCiphers_InitializesGenerator()
+    {
+        // Issue #2: Fixture-based org + generated ciphers should resolve domain from fixture
+        // This test verifies that when a preset uses a fixture org (no explicit domain)
+        // but wants to generate ciphers (needs domain for generator), the domain is
+        // automatically resolved by reading the org fixture.
+
+        var services = new ServiceCollection();
+        var builder = services.AddRecipe("fixture-org-test");
+
+        builder
+            .UseOrganization("dunder-mifflin")  // Fixture org (domain in fixture)
+            .AddOwner()
+            .WithGenerator("dundermifflin.com")  // Generator needs domain
+            .AddCiphers(50);
+
+        // This should NOT throw "Generated ciphers require a generator"
+        builder.Validate();
+
+        using var provider = services.BuildServiceProvider();
+        var steps = provider.GetKeyedServices<IStep>("fixture-org-test").ToList();
+
+        Assert.NotNull(steps);
+        Assert.NotEmpty(steps);
+    }
+}
diff --git a/test/SeederApi.IntegrationTest/Properties/launchSettings.json b/test/SeederApi.IntegrationTest/Properties/launchSettings.json
new file mode 100644
index 0000000000..9fa48f5841
--- /dev/null
+++ b/test/SeederApi.IntegrationTest/Properties/launchSettings.json
@@ -0,0 +1,12 @@
+{
+  "profiles": {
+    "SeederApi.IntegrationTest": {
+      "commandName": "Project",
+      "launchBrowser": true,
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      },
+      "applicationUrl": "https://localhost:53205;http://localhost:53206"
+    }
+  }
+}
\ No newline at end of file
diff --git a/test/SeederApi.IntegrationTest/RecipeBuilderValidationTests.cs b/test/SeederApi.IntegrationTest/RecipeBuilderValidationTests.cs
new file mode 100644
index 0000000000..38b1049b6d
--- /dev/null
+++ b/test/SeederApi.IntegrationTest/RecipeBuilderValidationTests.cs
@@ -0,0 +1,157 @@
+using Bit.Seeder;
+using Bit.Seeder.Pipeline;
+using Xunit;
+
+namespace Bit.SeederApi.IntegrationTest;
+
+public class RecipeBuilderValidationTests
+{
+    [Fact]
+    public void UseRoster_AfterAddUsers_ThrowsInvalidOperationException()
+    {
+        var services = new ServiceCollection();
+        var builder = services.AddRecipe("test");
+
+        builder.AddUsers(10);
+        var ex = Assert.Throws<InvalidOperationException>(() => builder.UseRoster("test"));
+        Assert.Contains("Cannot call UseRoster() after AddUsers()", ex.Message);
+    }
+
+    [Fact]
+    public void AddUsers_AfterUseRoster_ThrowsInvalidOperationException()
+    {
+        var services = new ServiceCollection();
+        var builder = services.AddRecipe("test");
+
+        builder.UseRoster("test");
+        var ex = Assert.Throws<InvalidOperationException>(() => builder.AddUsers(10));
+        Assert.Contains("Cannot call AddUsers() after UseRoster()", ex.Message);
+    }
+
+    [Fact]
+    public void UseCiphers_AfterAddCiphers_ThrowsInvalidOperationException()
+    {
+        var services = new ServiceCollection();
+        var builder = services.AddRecipe("test");
+
+        builder.AddCiphers(10);
+        var ex = Assert.Throws<InvalidOperationException>(() => builder.UseCiphers("test"));
+        Assert.Contains("Cannot call UseCiphers() after AddCiphers()", ex.Message);
+    }
+
+    [Fact]
+    public void AddCiphers_AfterUseCiphers_ThrowsInvalidOperationException()
+    {
+        var services = new ServiceCollection();
+        var builder = services.AddRecipe("test");
+
+        builder.UseCiphers("test");
+        var ex = Assert.Throws<InvalidOperationException>(() => builder.AddCiphers(10));
+        Assert.Contains("Cannot call AddCiphers() after UseCiphers()", ex.Message);
+    }
+
+    [Fact]
+    public void AddGroups_WithoutUsers_ThrowsInvalidOperationException()
+    {
+        var services = new ServiceCollection();
+        var builder = services.AddRecipe("test");
+
+        var ex = Assert.Throws<InvalidOperationException>(() => builder.AddGroups(5));
+        Assert.Contains("Groups require users", ex.Message);
+    }
+
+    [Fact]
+    public void AddCollections_WithoutUsers_ThrowsInvalidOperationException()
+    {
+        var services = new ServiceCollection();
+        var builder = services.AddRecipe("test");
+
+        var ex = Assert.Throws<InvalidOperationException>(() => builder.AddCollections(5));
+        Assert.Contains("Collections require users", ex.Message);
+    }
+
+    [Fact]
+    public void AddGroups_AfterAddUsers_Succeeds()
+    {
+        var services = new ServiceCollection();
+        var builder = services.AddRecipe("test");
+
+        builder.AddUsers(10);
+        builder.AddGroups(5);
+    }
+
+    [Fact]
+    public void AddCollections_AfterUseRoster_Succeeds()
+    {
+        var services = new ServiceCollection();
+        var builder = services.AddRecipe("test");
+
+        builder.UseRoster("test");
+        builder.AddCollections(5);
+    }
+
+    [Fact]
+    public void Validate_WithoutOrg_ThrowsInvalidOperationException()
+    {
+        var services = new ServiceCollection();
+        var builder = services.AddRecipe("test");
+
+        builder.AddOwner();
+        var ex = Assert.Throws<InvalidOperationException>(() => builder.Validate());
+        Assert.Contains("Organization is required", ex.Message);
+    }
+
+    [Fact]
+    public void Validate_WithoutOwner_ThrowsInvalidOperationException()
+    {
+        var services = new ServiceCollection();
+        var builder = services.AddRecipe("test");
+
+        builder.UseOrganization("test");
+        var ex = Assert.Throws<InvalidOperationException>(() => builder.Validate());
+        Assert.Contains("Owner is required", ex.Message);
+    }
+
+    [Fact]
+    public void Validate_AddCiphersWithoutGenerator_ThrowsInvalidOperationException()
+    {
+        var services = new ServiceCollection();
+        var builder = services.AddRecipe("test");
+
+        builder.UseOrganization("test");
+        builder.AddOwner();
+        builder.AddUsers(10);
+        builder.AddCiphers(50);
+        var ex = Assert.Throws<InvalidOperationException>(() => builder.Validate());
+        Assert.Contains("Generated ciphers require a generator", ex.Message);
+    }
+
+    [Fact]
+    public void StepsExecuteInRegistrationOrder()
+    {
+        var services = new ServiceCollection();
+        var builder = services.AddRecipe("test");
+
+        builder.UseOrganization("test-org");
+        builder.AddOwner();
+        builder.WithGenerator("test.com");
+        builder.AddUsers(5);
+        builder.AddGroups(2);
+        builder.AddCollections(3);
+        builder.AddCiphers(10);
+
+        builder.Validate();
+
+        using var provider = services.BuildServiceProvider();
+        var steps = provider.GetKeyedServices<IStep>("test").ToList();
+
+        Assert.Equal(7, steps.Count);
+
+        // Verify steps are wrapped in OrderedStep with sequential order values
+        var orderedSteps = steps.Cast<OrderedStep>().ToList();
+        for (var i = 0; i < orderedSteps.Count; i++)
+        {
+            Assert.Equal(i, orderedSteps[i].Order);
+        }
+    }
+}
diff --git a/test/SeederApi.IntegrationTest/SeedReaderTests.cs b/test/SeederApi.IntegrationTest/SeedReaderTests.cs
new file mode 100644
index 0000000000..34adf94da9
--- /dev/null
+++ b/test/SeederApi.IntegrationTest/SeedReaderTests.cs
@@ -0,0 +1,128 @@
+using Bit.Seeder.Models;
+using Bit.Seeder.Services;
+using Xunit;
+
+namespace Bit.SeederApi.IntegrationTest;
+
+public class SeedReaderTests
+{
+    private readonly SeedReader _reader = new();
+
+    [Fact]
+    public void ListAvailable_ReturnsAllSeedFiles()
+    {
+        var available = _reader.ListAvailable();
+
+        Assert.Contains("ciphers.autofill-testing", available);
+        Assert.Contains("ciphers.public-site-logins", available);
+        Assert.Contains("organizations.dunder-mifflin", available);
+        Assert.Contains("rosters.dunder-mifflin", available);
+        Assert.Contains("presets.dunder-mifflin-full", available);
+        Assert.Contains("presets.large-enterprise", available);
+        Assert.Equal(6, available.Count);
+    }
+
+    [Fact]
+    public void Read_AutofillTesting_DeserializesAllItems()
+    {
+        var seedFile = _reader.Read<SeedFile>("ciphers.autofill-testing");
+
+        Assert.Equal(18, seedFile.Items.Count);
+
+        var types = seedFile.Items.Select(i => i.Type).Distinct().OrderBy(t => t).ToList();
+        Assert.Contains("login", types);
+        Assert.Contains("card", types);
+        Assert.Contains("identity", types);
+
+        var logins = seedFile.Items.Where(i => i.Type == "login").ToList();
+        Assert.All(logins, l => Assert.NotEmpty(l.Login!.Uris!));
+    }
+
+    [Fact]
+    public void Read_PublicSiteLogins_DeserializesAllItems()
+    {
+        var seedFile = _reader.Read<SeedFile>("ciphers.public-site-logins");
+
+        Assert.True(seedFile.Items.Count >= 90,
+            $"Expected at least 90 public site logins, got {seedFile.Items.Count}");
+    }
+
+    [Fact]
+    public void Read_NonExistentSeed_ThrowsWithAvailableList()
+    {
+        var ex = Assert.Throws<InvalidOperationException>(
+            () => _reader.Read<SeedFile>("does-not-exist"));
+
+        Assert.Contains("does-not-exist", ex.Message);
+        Assert.Contains("ciphers.autofill-testing", ex.Message);
+    }
+
+    [Fact]
+    public void Read_CipherSeeds_ItemNamesAreUnique()
+    {
+        var cipherSeeds = _reader.ListAvailable()
+            .Where(n => n.StartsWith("ciphers."));
+
+        foreach (var seedName in cipherSeeds)
+        {
+            var seedFile = _reader.Read<SeedFile>(seedName);
+            var duplicates = seedFile.Items
+                .GroupBy(i => i.Name)
+                .Where(g => g.Count() > 1)
+                .Select(g => g.Key)
+                .ToList();
+
+            Assert.True(duplicates.Count == 0,
+                $"Seed '{seedName}' has duplicate item names: {string.Join(", ", duplicates)}");
+        }
+    }
+
+    [Fact]
+    public void Read_DunderMifflin_DeserializesOrganization()
+    {
+        var org = _reader.Read<SeedOrganization>("organizations.dunder-mifflin");
+
+        Assert.Equal("Dunder Mifflin", org.Name);
+        Assert.Equal("dundermifflin.com", org.Domain);
+        Assert.Equal(70, org.Seats);
+    }
+
+    [Fact]
+    public void Read_DunderMifflinRoster_DeserializesRoster()
+    {
+        var roster = _reader.Read<SeedRoster>("rosters.dunder-mifflin");
+
+        Assert.Equal(58, roster.Users.Count);
+        Assert.NotNull(roster.Groups);
+        Assert.Equal(14, roster.Groups.Count);
+        Assert.NotNull(roster.Collections);
+        Assert.Equal(15, roster.Collections.Count);
+
+        // Verify no duplicate email prefixes
+        var prefixes = roster.Users
+            .Select(u => $"{u.FirstName}.{u.LastName}".ToLowerInvariant())
+            .ToList();
+        Assert.Equal(prefixes.Count, prefixes.Distinct().Count());
+
+        // Verify all group members reference valid users
+        var prefixSet = new HashSet<string>(prefixes, StringComparer.OrdinalIgnoreCase);
+        foreach (var group in roster.Groups)
+        {
+            Assert.All(group.Members, m => Assert.Contains(m, prefixSet));
+        }
+
+        // Verify all collection user/group refs are valid
+        var groupNames = new HashSet<string>(roster.Groups.Select(g => g.Name), StringComparer.OrdinalIgnoreCase);
+        foreach (var collection in roster.Collections)
+        {
+            if (collection.Groups is not null)
+            {
+                Assert.All(collection.Groups, cg => Assert.Contains(cg.Group, groupNames));
+            }
+            if (collection.Users is not null)
+            {
+                Assert.All(collection.Users, cu => Assert.Contains(cu.User, prefixSet));
+            }
+        }
+    }
+}
diff --git a/util/DbSeederUtility/Program.cs b/util/DbSeederUtility/Program.cs
index 60936ca67d..969b453ef7 100644
--- a/util/DbSeederUtility/Program.cs
+++ b/util/DbSeederUtility/Program.cs
@@ -1,4 +1,5 @@
-using AutoMapper;
+using System.Diagnostics;
+using AutoMapper;
 using Bit.Core.Entities;
 using Bit.Infrastructure.EntityFramework.Repositories;
 using Bit.Seeder.Recipes;
@@ -77,4 +78,112 @@ public class Program
             Console.WriteLine($"{original} -> {mangled}");
         }
     }
+
+    [Command("seed", Description = "Seed database using fixture-based presets")]
+    public void Seed(SeedArgs args)
+    {
+        try
+        {
+            args.Validate();
+
+            // Handle list mode - no database needed
+            if (args.List)
+            {
+                var available = OrganizationFromPresetRecipe.ListAvailable();
+                PrintAvailableSeeds(available);
+                return;
+            }
+
+            // Create service provider - same pattern as other commands
+            var services = new ServiceCollection();
+            ServiceCollectionExtension.ConfigureServices(services, enableMangling: args.Mangle);
+            var serviceProvider = services.BuildServiceProvider();
+
+            using var scope = serviceProvider.CreateScope();
+            var scopedServices = scope.ServiceProvider;
+
+            var db = scopedServices.GetRequiredService<DatabaseContext>();
+            var mapper = scopedServices.GetRequiredService<IMapper>();
+            var passwordHasher = scopedServices.GetRequiredService<IPasswordHasher<User>>();
+            var manglerService = scopedServices.GetRequiredService<IManglerService>();
+
+            // Create recipe - CLI is "dumb", recipe handles complexity
+            var recipe = new OrganizationFromPresetRecipe(db, mapper, passwordHasher, manglerService);
+
+            var stopwatch = Stopwatch.StartNew();
+
+            Console.WriteLine($"Seeding organization from preset '{args.Preset}'...");
+            var result = recipe.Seed(args.Preset!);
+
+            stopwatch.Stop();
+            PrintSeedResult(result, stopwatch.Elapsed);
+        }
+        catch (Exception ex) when (ex is ArgumentException or InvalidOperationException)
+        {
+            Console.Error.WriteLine($"Error: {ex.Message}");
+            Environment.Exit(1);
+        }
+    }
+
+    private static void PrintAvailableSeeds(AvailableSeeds available)
+    {
+        Console.WriteLine("Available Presets:");
+        foreach (var preset in available.Presets)
+        {
+            Console.WriteLine($"  - {preset}");
+        }
+        Console.WriteLine();
+
+        Console.WriteLine("Available Fixtures:");
+        foreach (var (category, fixtures) in available.Fixtures.OrderBy(kvp => kvp.Key))
+        {
+            // Guard: Skip empty or single-character categories to prevent IndexOutOfRangeException
+            if (string.IsNullOrEmpty(category) || category.Length < 2)
+            {
+                continue;
+            }
+
+            var categoryName = char.ToUpperInvariant(category[0]) + category[1..];
+            Console.WriteLine($"  {categoryName}:");
+            foreach (var fixture in fixtures)
+            {
+                Console.WriteLine($"    - {fixture}");
+            }
+        }
+
+        Console.WriteLine();
+        Console.WriteLine("Use: DbSeeder.exe seed --preset <name>");
+    }
+
+    private static void PrintSeedResult(SeedResult result, TimeSpan elapsed)
+    {
+        Console.WriteLine($"✓ Created organization (ID: {result.OrganizationId})");
+
+        if (result.OwnerEmail is not null)
+        {
+            Console.WriteLine($"✓ Owner: {result.OwnerEmail}");
+        }
+
+        if (result.UsersCount > 0)
+        {
+            Console.WriteLine($"✓ Created {result.UsersCount} users");
+        }
+
+        if (result.GroupsCount > 0)
+        {
+            Console.WriteLine($"✓ Created {result.GroupsCount} groups");
+        }
+
+        if (result.CollectionsCount > 0)
+        {
+            Console.WriteLine($"✓ Created {result.CollectionsCount} collections");
+        }
+
+        if (result.CiphersCount > 0)
+        {
+            Console.WriteLine($"✓ Created {result.CiphersCount} ciphers");
+        }
+
+        Console.WriteLine($"Done in {elapsed.TotalSeconds:F1}s");
+    }
 }
diff --git a/util/DbSeederUtility/README.md b/util/DbSeederUtility/README.md
index 154cbd018b..e2f2b8f6b1 100644
--- a/util/DbSeederUtility/README.md
+++ b/util/DbSeederUtility/README.md
@@ -1,66 +1,68 @@
 # Bitwarden Database Seeder Utility
 
-A command-line utility for generating and managing test data for Bitwarden databases.
+A CLI wrapper around the Seeder library for generating test data in your local Bitwarden database.
 
-## Overview
+## Getting Started
 
-DbSeederUtility is an executable wrapper around the Seeder class library that provides a convenient command-line
-interface for executing seed-recipes in your local environment.
+Build and run from the `util/DbSeederUtility` directory:
 
-## Installation
-
-The utility can be built and run as a .NET 8 application:
-
-```
+```bash
 dotnet build
 dotnet run -- <command> [options]
 ```
 
-Or directly using the compiled executable:
+**Login Credentials:** All seeded users use password `asdfasdfasdf`. The owner email is `owner@<domain>`.
 
-```
-DbSeeder.exe <command> [options]
-```
+## Commands
 
-## Examples
-
-### Generate and load test organization
+### `seed` - Fixture-Based Seeding
 
 ```bash
-# Generate an organization called "seeded" with 10000 users using the @large.test email domain.
-# Login using "owner@large.test" with password "asdfasdfasdf"
-DbSeeder.exe organization -n seeded -u 10000 -d large.test
+# List available presets and fixtures
+dotnet run -- seed --list
 
-# Generate an organization with 5 users and 100 encrypted ciphers
-DbSeeder.exe vault-organization -n TestOrg -u 5 -d test.com -c 100
+# Load the Dunder Mifflin preset (58 users, 14 groups, 15 collections, ciphers)
+dotnet run -- seed --preset dunder-mifflin-full
 
-# Generate with Spotify-style collections (tribes, chapters, guilds)
-DbSeeder.exe vault-organization -n TestOrg -u 10 -d test.com -c 50 -o Spotify
-
-# Generate a small test organization with ciphers for manual testing
-DbSeeder.exe vault-organization -n DevOrg -u 2 -d dev.local -c 10
-
-# Generate an organization using a traditional structure
-dotnet run --project DbSeederUtility.csproj -- vault-organization -n Test001 -d test001.com -u 50 -c 1000 -g 15 -o Traditional -m
-
-# Generate an organization using a modern structure with a small vault
-dotnet run --project DbSeederUtility.csproj -- vault-organization -n Test002 -d test002.com -u 500 -c 10000 -g 85 -o Modern -m
-
-# Generate an organization using a spotify structure with a large vault
-dotnet run --project DbSeederUtility.csproj -- vault-organization -n Test003 -d test003.com -u 8000 -c 100000 -g 125 -o Spotify -m
-
-# Generate an organization using a traditional structure with a very small vault with European regional data
-dotnet run --project DbSeederUtility.csproj  -- vault-organization -n “TestOneEurope” -u 10 -c 100 -g 5 -d testOneEurope.com -o Traditional --region Europe
-
-# Generate an organization using a traditional structure with a very small vault with Asia Pacific regional data
-dotnet run --project DbSeederUtility.csproj  -- vault-organization -n “TestOneAsiaPacific” -u 17 -c 600 -g 12 -d testOneAsiaPacific.com -o Traditional --region AsiaPacific
+# Load with ID mangling for test isolation
+dotnet run -- seed --preset dunder-mifflin-full --mangle
 
+# Large enterprise preset for performance testing
+dotnet run -- seed --preset large-enterprise
 ```
 
-## Dependencies
+### `organization` - Users Only (No Vault Data)
 
-This utility depends on:
+```bash
+# 100 users
+dotnet run -- organization -n MyOrg -u 100 -d myorg.com
 
-- The Seeder class library
-- CommandDotNet for command-line parsing
-- .NET 8.0 runtime
+# 10,000 users for load testing
+dotnet run -- organization -n seeded -u 10000 -d large.test
+```
+
+### `vault-organization` - Users + Encrypted Vault Data
+
+```bash
+# Tiny org — quick sanity check
+dotnet run -- vault-organization -n SmallOrg -d small.test -u 3 -c 10 -g 5 -o Traditional -m
+
+# Mid-size Traditional org with realistic status mix
+dotnet run -- vault-organization -n MidOrg -d mid.test -u 50 -c 1000 -g 15 -o Traditional -m
+
+# Mid-size with dense cipher-to-user ratio
+dotnet run -- vault-organization -n DenseOrg -d dense.test -u 75 -c 650 -g 20 -o Traditional -m
+
+# Large Modern org
+dotnet run -- vault-organization -n LargeOrg -d large.test -u 500 -c 10000 -g 85 -o Modern -m
+
+# Stress test — massive Spotify-style org
+dotnet run -- vault-organization -n StressOrg -d stress.test -u 8000 -c 100000 -g 125 -o Spotify -m
+
+# Regional data variants
+dotnet run -- vault-organization -n EuropeOrg -d europe.test -u 10 -c 100 -g 5 --region Europe
+dotnet run -- vault-organization -n ApacOrg -d apac.test -u 17 -c 600 -g 12 --region AsiaPacific
+
+# With ID mangling for test isolation (prevents collisions with existing data)
+dotnet run -- vault-organization -n IsolatedOrg -d isolated.test -u 5 -c 25 -g 4 -o Spotify --mangle
+```
diff --git a/util/DbSeederUtility/SeedArgs.cs b/util/DbSeederUtility/SeedArgs.cs
new file mode 100644
index 0000000000..699a065de4
--- /dev/null
+++ b/util/DbSeederUtility/SeedArgs.cs
@@ -0,0 +1,35 @@
+using CommandDotNet;
+
+namespace Bit.DbSeederUtility;
+
+/// <summary>
+/// CLI argument model for the seed command.
+/// Supports loading presets from embedded resources.
+/// </summary>
+public class SeedArgs : IArgumentModel
+{
+    [Option('p', "preset", Description = "Name of embedded preset to load (e.g., 'dunder-mifflin-full')")]
+    public string? Preset { get; set; }
+
+    [Option('l', "list", Description = "List all available presets and fixtures")]
+    public bool List { get; set; }
+
+    [Option("mangle", Description = "Enable mangling for test isolation")]
+    public bool Mangle { get; set; }
+
+    public void Validate()
+    {
+        // List mode is standalone
+        if (List)
+        {
+            return;
+        }
+
+        // Must specify preset
+        if (string.IsNullOrEmpty(Preset))
+        {
+            throw new ArgumentException(
+                "--preset must be specified. Use --list to see available presets.");
+        }
+    }
+}
diff --git a/util/DbSeederUtility/ServiceCollectionExtension.cs b/util/DbSeederUtility/ServiceCollectionExtension.cs
index 26a198d03a..0a2288a4c2 100644
--- a/util/DbSeederUtility/ServiceCollectionExtension.cs
+++ b/util/DbSeederUtility/ServiceCollectionExtension.cs
@@ -25,6 +25,7 @@ public static class ServiceCollectionExtension
         });
         services.AddSingleton(globalSettings);
         services.AddSingleton<IPasswordHasher<User>, PasswordHasher<User>>();
+        services.TryAddSingleton<ISeedReader, SeedReader>();
 
         // Add Data Protection services
         services.AddDataProtection()
diff --git a/util/Seeder/CLAUDE.md b/util/Seeder/CLAUDE.md
index 21e3f03fb1..dbdc13dc1f 100644
--- a/util/Seeder/CLAUDE.md
+++ b/util/Seeder/CLAUDE.md
@@ -24,12 +24,31 @@ dotnet test test/SeederApi.IntegrationTest/ --filter "FullyQualifiedName~TestMet
 ```
 Need to create test data?
 ├─ ONE entity with encryption? → Factory
-├─ MANY entities as cohesive operation? → Recipe
-├─ Complete test scenario with ID mangling for SeederApi? → Scene
+├─ MANY entities as cohesive operation? → Recipe or Pipeline
+├─ Flexible preset-based seeding? → Pipeline (RecipeBuilder + Steps)
+├─ Complete test scenario with ID mangling? → Scene
 ├─ READ existing seeded data? → Query
 └─ Data transformation SDK ↔ Server? → Model
 ```
 
+## Pipeline Architecture
+
+**Modern pattern for composable fixture-based and generated seeding.**
+
+**Flow**: Preset JSON → PresetLoader → RecipeBuilder → IStep[] → RecipeExecutor → SeederContext → BulkCommitter
+
+**Key actors**:
+
+- **RecipeBuilder**: Fluent API with dependency validation
+- **IStep**: Isolated units of work (CreateOrganizationStep, CreateUsersStep, etc.)
+- **SeederContext**: Shared mutable state bag (NOT thread-safe)
+- **RecipeExecutor**: Executes steps sequentially, captures statistics, commits via BulkCommitter
+- **PresetExecutor**: Orchestrates preset loading and execution
+
+**Phase order**: Org → Owner → Generator → Roster → Users → Groups → Collections → Ciphers
+
+See `Pipeline/` folder for implementation.
+
 ## The Recipe Contract
 
 Recipes follow strict rules:
diff --git a/util/Seeder/Factories/CardCipherSeeder.cs b/util/Seeder/Factories/CardCipherSeeder.cs
index 28355bbd62..e6f4518f11 100644
--- a/util/Seeder/Factories/CardCipherSeeder.cs
+++ b/util/Seeder/Factories/CardCipherSeeder.cs
@@ -26,4 +26,32 @@ internal static class CardCipherSeeder
         var encrypted = CipherEncryption.Encrypt(cipherView, encryptionKey);
         return CipherEncryption.CreateEntity(encrypted, encrypted.ToCardData(), CipherType.Card, organizationId, userId);
     }
+
+    internal static Cipher CreateFromSeed(
+        string encryptionKey,
+        SeedVaultItem item,
+        Guid? organizationId = null,
+        Guid? userId = null)
+    {
+        var cipherView = new CipherViewDto
+        {
+            OrganizationId = organizationId,
+            Name = item.Name,
+            Notes = item.Notes,
+            Type = CipherTypes.Card,
+            Card = item.Card == null ? null : new CardViewDto
+            {
+                CardholderName = item.Card.CardholderName,
+                Brand = item.Card.Brand,
+                Number = item.Card.Number,
+                ExpMonth = item.Card.ExpMonth,
+                ExpYear = item.Card.ExpYear,
+                Code = item.Card.Code
+            },
+            Fields = SeedItemMapping.MapFields(item.Fields)
+        };
+
+        var encrypted = CipherEncryption.Encrypt(cipherView, encryptionKey);
+        return CipherEncryption.CreateEntity(encrypted, encrypted.ToCardData(), CipherType.Card, organizationId, userId);
+    }
 }
diff --git a/util/Seeder/Factories/CollectionGroupSeeder.cs b/util/Seeder/Factories/CollectionGroupSeeder.cs
new file mode 100644
index 0000000000..c1bd57cf75
--- /dev/null
+++ b/util/Seeder/Factories/CollectionGroupSeeder.cs
@@ -0,0 +1,23 @@
+using Bit.Core.Entities;
+
+namespace Bit.Seeder.Factories;
+
+internal static class CollectionGroupSeeder
+{
+    internal static CollectionGroup Create(
+        Guid collectionId,
+        Guid groupId,
+        bool readOnly = false,
+        bool hidePasswords = false,
+        bool manage = false)
+    {
+        return new CollectionGroup
+        {
+            CollectionId = collectionId,
+            GroupId = groupId,
+            ReadOnly = readOnly,
+            HidePasswords = hidePasswords,
+            Manage = manage
+        };
+    }
+}
diff --git a/util/Seeder/Factories/IdentityCipherSeeder.cs b/util/Seeder/Factories/IdentityCipherSeeder.cs
index 1f0f5975bb..c6d340d400 100644
--- a/util/Seeder/Factories/IdentityCipherSeeder.cs
+++ b/util/Seeder/Factories/IdentityCipherSeeder.cs
@@ -26,4 +26,43 @@ internal static class IdentityCipherSeeder
         var encrypted = CipherEncryption.Encrypt(cipherView, encryptionKey);
         return CipherEncryption.CreateEntity(encrypted, encrypted.ToIdentityData(), CipherType.Identity, organizationId, userId);
     }
+
+    internal static Cipher CreateFromSeed(
+        string encryptionKey,
+        SeedVaultItem item,
+        Guid? organizationId = null,
+        Guid? userId = null)
+    {
+        var cipherView = new CipherViewDto
+        {
+            OrganizationId = organizationId,
+            Name = item.Name,
+            Notes = item.Notes,
+            Type = CipherTypes.Identity,
+            Identity = item.Identity == null ? null : new IdentityViewDto
+            {
+                FirstName = item.Identity.FirstName,
+                MiddleName = item.Identity.MiddleName,
+                LastName = item.Identity.LastName,
+                Address1 = item.Identity.Address1,
+                Address2 = item.Identity.Address2,
+                Address3 = item.Identity.Address3,
+                City = item.Identity.City,
+                State = item.Identity.State,
+                PostalCode = item.Identity.PostalCode,
+                Country = item.Identity.Country,
+                Company = item.Identity.Company,
+                Email = item.Identity.Email,
+                Phone = item.Identity.Phone,
+                SSN = item.Identity.Ssn,
+                Username = item.Identity.Username,
+                PassportNumber = item.Identity.PassportNumber,
+                LicenseNumber = item.Identity.LicenseNumber
+            },
+            Fields = SeedItemMapping.MapFields(item.Fields)
+        };
+
+        var encrypted = CipherEncryption.Encrypt(cipherView, encryptionKey);
+        return CipherEncryption.CreateEntity(encrypted, encrypted.ToIdentityData(), CipherType.Identity, organizationId, userId);
+    }
 }
diff --git a/util/Seeder/Factories/LoginCipherSeeder.cs b/util/Seeder/Factories/LoginCipherSeeder.cs
index 76fcf57764..4683a2c7b6 100644
--- a/util/Seeder/Factories/LoginCipherSeeder.cs
+++ b/util/Seeder/Factories/LoginCipherSeeder.cs
@@ -40,4 +40,34 @@ internal static class LoginCipherSeeder
         var encrypted = CipherEncryption.Encrypt(cipherView, encryptionKey);
         return CipherEncryption.CreateEntity(encrypted, encrypted.ToLoginData(), CipherType.Login, organizationId, userId);
     }
+
+    internal static Cipher CreateFromSeed(
+        string encryptionKey,
+        SeedVaultItem item,
+        Guid? organizationId = null,
+        Guid? userId = null)
+    {
+        var cipherView = new CipherViewDto
+        {
+            OrganizationId = organizationId,
+            Name = item.Name,
+            Notes = item.Notes,
+            Type = CipherTypes.Login,
+            Login = item.Login == null ? null : new LoginViewDto
+            {
+                Username = item.Login.Username,
+                Password = item.Login.Password,
+                Totp = item.Login.Totp,
+                Uris = item.Login.Uris?.Select(u => new LoginUriViewDto
+                {
+                    Uri = u.Uri,
+                    Match = SeedItemMapping.MapUriMatchType(u.Match)
+                }).ToList()
+            },
+            Fields = SeedItemMapping.MapFields(item.Fields)
+        };
+
+        var encrypted = CipherEncryption.Encrypt(cipherView, encryptionKey);
+        return CipherEncryption.CreateEntity(encrypted, encrypted.ToLoginData(), CipherType.Login, organizationId, userId);
+    }
 }
diff --git a/util/Seeder/Factories/SecureNoteCipherSeeder.cs b/util/Seeder/Factories/SecureNoteCipherSeeder.cs
index 3fb6dab2ea..9756d1f67a 100644
--- a/util/Seeder/Factories/SecureNoteCipherSeeder.cs
+++ b/util/Seeder/Factories/SecureNoteCipherSeeder.cs
@@ -25,4 +25,24 @@ internal static class SecureNoteCipherSeeder
         var encrypted = CipherEncryption.Encrypt(cipherView, encryptionKey);
         return CipherEncryption.CreateEntity(encrypted, encrypted.ToSecureNoteData(), CipherType.SecureNote, organizationId, userId);
     }
+
+    internal static Cipher CreateFromSeed(
+        string encryptionKey,
+        SeedVaultItem item,
+        Guid? organizationId = null,
+        Guid? userId = null)
+    {
+        var cipherView = new CipherViewDto
+        {
+            OrganizationId = organizationId,
+            Name = item.Name,
+            Notes = item.Notes,
+            Type = CipherTypes.SecureNote,
+            SecureNote = new SecureNoteViewDto { Type = 0 },
+            Fields = SeedItemMapping.MapFields(item.Fields)
+        };
+
+        var encrypted = CipherEncryption.Encrypt(cipherView, encryptionKey);
+        return CipherEncryption.CreateEntity(encrypted, encrypted.ToSecureNoteData(), CipherType.SecureNote, organizationId, userId);
+    }
 }
diff --git a/util/Seeder/Factories/SeedItemMapping.cs b/util/Seeder/Factories/SeedItemMapping.cs
new file mode 100644
index 0000000000..91b5d41aeb
--- /dev/null
+++ b/util/Seeder/Factories/SeedItemMapping.cs
@@ -0,0 +1,35 @@
+using Bit.Seeder.Models;
+
+namespace Bit.Seeder.Factories;
+
+/// <summary>
+/// Shared mapping helpers for converting SeedItem fields to CipherViewDto fields.
+/// </summary>
+internal static class SeedItemMapping
+{
+    internal static int MapFieldType(string type) => type switch
+    {
+        "hidden" => 1,
+        "boolean" => 2,
+        "linked" => 3,
+        _ => 0 // text
+    };
+
+    internal static List<FieldViewDto>? MapFields(List<SeedField>? fields) =>
+        fields?.Select(f => new FieldViewDto
+        {
+            Name = f.Name,
+            Value = f.Value,
+            Type = MapFieldType(f.Type)
+        }).ToList();
+
+    internal static int MapUriMatchType(string match) => match switch
+    {
+        "host" => 1,
+        "startsWith" => 2,
+        "exact" => 3,
+        "regex" => 4,
+        "never" => 5,
+        _ => 0 // domain
+    };
+}
diff --git a/util/Seeder/IStep.cs b/util/Seeder/IStep.cs
new file mode 100644
index 0000000000..af5e529624
--- /dev/null
+++ b/util/Seeder/IStep.cs
@@ -0,0 +1,8 @@
+using Bit.Seeder.Pipeline;
+
+namespace Bit.Seeder;
+
+public interface IStep
+{
+    void Execute(SeederContext context);
+}
diff --git a/util/Seeder/Models/SeedModels.cs b/util/Seeder/Models/SeedModels.cs
new file mode 100644
index 0000000000..6c7a6eaf3b
--- /dev/null
+++ b/util/Seeder/Models/SeedModels.cs
@@ -0,0 +1,122 @@
+namespace Bit.Seeder.Models;
+
+internal record SeedFile
+{
+    public required List<SeedVaultItem> Items { get; init; }
+}
+
+internal record SeedVaultItem
+{
+    public required string Type { get; init; }
+    public required string Name { get; init; }
+    public string? Notes { get; init; }
+    public SeedLogin? Login { get; init; }
+    public SeedCard? Card { get; init; }
+    public SeedIdentity? Identity { get; init; }
+    public List<SeedField>? Fields { get; init; }
+}
+
+internal record SeedLogin
+{
+    public string? Username { get; init; }
+    public string? Password { get; init; }
+    public List<SeedLoginUri>? Uris { get; init; }
+    public string? Totp { get; init; }
+}
+
+internal record SeedLoginUri
+{
+    public required string Uri { get; init; }
+    public string Match { get; init; } = "domain";
+}
+
+internal record SeedCard
+{
+    public string? CardholderName { get; init; }
+    public string? Brand { get; init; }
+    public string? Number { get; init; }
+    public string? ExpMonth { get; init; }
+    public string? ExpYear { get; init; }
+    public string? Code { get; init; }
+}
+
+internal record SeedIdentity
+{
+    public string? FirstName { get; init; }
+    public string? MiddleName { get; init; }
+    public string? LastName { get; init; }
+    public string? Address1 { get; init; }
+    public string? Address2 { get; init; }
+    public string? Address3 { get; init; }
+    public string? City { get; init; }
+    public string? State { get; init; }
+    public string? PostalCode { get; init; }
+    public string? Country { get; init; }
+    public string? Company { get; init; }
+    public string? Email { get; init; }
+    public string? Phone { get; init; }
+    public string? Ssn { get; init; }
+    public string? Username { get; init; }
+    public string? PassportNumber { get; init; }
+    public string? LicenseNumber { get; init; }
+}
+
+internal record SeedField
+{
+    public string? Name { get; init; }
+    public string? Value { get; init; }
+    public string Type { get; init; } = "text";
+}
+
+internal record SeedOrganization
+{
+    public required string Name { get; init; }
+    public required string Domain { get; init; }
+    public int Seats { get; init; } = 10;
+}
+
+internal record SeedRoster
+{
+    public required List<SeedRosterUser> Users { get; init; }
+    public List<SeedRosterGroup>? Groups { get; init; }
+    public List<SeedRosterCollection>? Collections { get; init; }
+}
+
+internal record SeedRosterUser
+{
+    public required string FirstName { get; init; }
+    public required string LastName { get; init; }
+    public string? Title { get; init; }
+    public string Role { get; init; } = "user";
+    public string? Branch { get; init; }
+    public string? Department { get; init; }
+}
+
+internal record SeedRosterGroup
+{
+    public required string Name { get; init; }
+    public required List<string> Members { get; init; }
+}
+
+internal record SeedRosterCollection
+{
+    public required string Name { get; init; }
+    public List<SeedRosterCollectionGroup>? Groups { get; init; }
+    public List<SeedRosterCollectionUser>? Users { get; init; }
+}
+
+internal record SeedRosterCollectionGroup
+{
+    public required string Group { get; init; }
+    public bool ReadOnly { get; init; }
+    public bool HidePasswords { get; init; }
+    public bool Manage { get; init; }
+}
+
+internal record SeedRosterCollectionUser
+{
+    public required string User { get; init; }
+    public bool ReadOnly { get; init; }
+    public bool HidePasswords { get; init; }
+    public bool Manage { get; init; }
+}
diff --git a/util/Seeder/Models/SeedPreset.cs b/util/Seeder/Models/SeedPreset.cs
new file mode 100644
index 0000000000..bc4e5467eb
--- /dev/null
+++ b/util/Seeder/Models/SeedPreset.cs
@@ -0,0 +1,46 @@
+namespace Bit.Seeder.Models;
+
+internal record SeedPreset
+{
+    public SeedPresetOrganization? Organization { get; init; }
+    public SeedPresetRoster? Roster { get; init; }
+    public SeedPresetUsers? Users { get; init; }
+    public SeedPresetGroups? Groups { get; init; }
+    public SeedPresetCollections? Collections { get; init; }
+    public SeedPresetCiphers? Ciphers { get; init; }
+}
+
+internal record SeedPresetOrganization
+{
+    public string? Fixture { get; init; }
+    public string? Name { get; init; }
+    public string? Domain { get; init; }
+    public int Seats { get; init; } = 10;
+}
+
+internal record SeedPresetRoster
+{
+    public string? Fixture { get; init; }
+}
+
+internal record SeedPresetUsers
+{
+    public int Count { get; init; }
+    public bool RealisticStatusMix { get; init; }
+}
+
+internal record SeedPresetGroups
+{
+    public int Count { get; init; }
+}
+
+internal record SeedPresetCollections
+{
+    public int Count { get; init; }
+}
+
+internal record SeedPresetCiphers
+{
+    public string? Fixture { get; init; }
+    public int Count { get; init; }
+}
diff --git a/util/Seeder/Pipeline/BulkCommitter.cs b/util/Seeder/Pipeline/BulkCommitter.cs
new file mode 100644
index 0000000000..fa0a89c9ec
--- /dev/null
+++ b/util/Seeder/Pipeline/BulkCommitter.cs
@@ -0,0 +1,87 @@
+using AutoMapper;
+using Bit.Infrastructure.EntityFramework.Repositories;
+using LinqToDB.Data;
+using LinqToDB.EntityFrameworkCore;
+using EfCollection = Bit.Infrastructure.EntityFramework.Models.Collection;
+using EfCollectionGroup = Bit.Infrastructure.EntityFramework.Models.CollectionGroup;
+using EfCollectionUser = Bit.Infrastructure.EntityFramework.Models.CollectionUser;
+using EfGroup = Bit.Infrastructure.EntityFramework.Models.Group;
+using EfGroupUser = Bit.Infrastructure.EntityFramework.Models.GroupUser;
+using EfOrganization = Bit.Infrastructure.EntityFramework.AdminConsole.Models.Organization;
+using EfOrganizationUser = Bit.Infrastructure.EntityFramework.Models.OrganizationUser;
+using EfUser = Bit.Infrastructure.EntityFramework.Models.User;
+
+namespace Bit.Seeder.Pipeline;
+
+/// <summary>
+/// Flushes accumulated entities from <see cref="SeederContext"/> to the database via BulkCopy.
+/// </summary>
+/// <remarks>
+/// Entities are committed in foreign-key-safe order (Organizations → Users → OrgUsers → …).
+/// Most Core entities require AutoMapper conversion to their EF counterparts before insert;
+/// a few (Cipher, CollectionCipher) share the same type across layers and copy directly.
+/// Each list is cleared after insert so the context is ready for the next pipeline run.
+///
+/// CollectionUser and CollectionGroup require an explicit table name in BulkCopyOptions because
+/// they lack both IEntityTypeConfiguration and .ToTable() mappings in DatabaseContext, so LinqToDB
+/// cannot resolve their table names automatically.
+/// </remarks>
+/// <seealso cref="SeederContext"/>
+/// <seealso cref="RecipeExecutor"/>
+internal sealed class BulkCommitter(DatabaseContext db, IMapper mapper)
+{
+    internal void Commit(SeederContext context)
+    {
+        MapCopyAndClear<Core.AdminConsole.Entities.Organization, EfOrganization>(context.Organizations);
+
+        MapCopyAndClear<Core.Entities.User, EfUser>(context.Users);
+
+        MapCopyAndClear<Core.Entities.OrganizationUser, EfOrganizationUser>(context.OrganizationUsers);
+
+        MapCopyAndClear<Core.AdminConsole.Entities.Group, EfGroup>(context.Groups);
+
+        MapCopyAndClear<Core.AdminConsole.Entities.GroupUser, EfGroupUser>(context.GroupUsers);
+
+        MapCopyAndClear<Core.Entities.Collection, EfCollection>(context.Collections);
+
+        MapCopyAndClear<Core.Entities.CollectionUser, EfCollectionUser>(context.CollectionUsers, nameof(Core.Entities.CollectionUser));
+
+        MapCopyAndClear<Core.Entities.CollectionGroup, EfCollectionGroup>(context.CollectionGroups, nameof(Core.Entities.CollectionGroup));
+
+        CopyAndClear(context.Ciphers);
+
+        CopyAndClear(context.CollectionCiphers);
+    }
+
+    private void MapCopyAndClear<TCore, TEf>(List<TCore> entities, string? tableName = null) where TEf : class
+    {
+        if (entities.Count is 0)
+        {
+            return;
+        }
+
+        var mapped = entities.Select(e => mapper.Map<TEf>(e));
+
+        if (tableName is not null)
+        {
+            db.BulkCopy(new BulkCopyOptions { TableName = tableName }, mapped);
+        }
+        else
+        {
+            db.BulkCopy(mapped);
+        }
+
+        entities.Clear();
+    }
+
+    private void CopyAndClear<T>(List<T> entities) where T : class
+    {
+        if (entities.Count is 0)
+        {
+            return;
+        }
+
+        db.BulkCopy(entities);
+        entities.Clear();
+    }
+}
diff --git a/util/Seeder/Pipeline/EntityRegistry.cs b/util/Seeder/Pipeline/EntityRegistry.cs
new file mode 100644
index 0000000000..45061b5479
--- /dev/null
+++ b/util/Seeder/Pipeline/EntityRegistry.cs
@@ -0,0 +1,60 @@
+namespace Bit.Seeder.Pipeline;
+
+/// <summary>
+/// Persistent cross-step reference store that survives bulk-commit flushes.
+/// </summary>
+/// <remarks>
+/// When <see cref="BulkCommitter"/> commits entities to the database, it clears the entity
+/// lists on <see cref="SeederContext"/> (users, groups, ciphers, etc.). The registry preserves
+/// the IDs and keys that downstream steps need to reference those already-committed entities
+/// — for example, a cipher step needs collection IDs to create join records.
+/// <para>
+/// Steps populate the registry as they create entities. Later steps read from it.
+/// <see cref="RecipeExecutor"/> calls <see cref="Clear"/> before each run to prevent stale state.
+/// </para>
+/// </remarks>
+internal sealed class EntityRegistry
+{
+    /// <summary>
+    /// A user's core IDs and symmetric key, needed for per-user encryption (e.g. personal folders).
+    /// </summary>
+    internal record UserDigest(Guid UserId, Guid OrgUserId, string SymmetricKey);
+
+    /// <summary>
+    /// Organization user IDs for hardened (key-bearing) members. Used by group and collection steps for assignment.
+    /// </summary>
+    internal List<Guid> HardenedOrgUserIds { get; } = [];
+
+    /// <summary>
+    /// Full user references including symmetric keys. Used for per-user encrypted content.
+    /// </summary>
+    /// <seealso cref="UserDigest"/>
+    internal List<UserDigest> UserDigests { get; } = [];
+
+    /// <summary>
+    /// Group IDs for collection-group assignment.
+    /// </summary>
+    internal List<Guid> GroupIds { get; } = [];
+
+    /// <summary>
+    /// Collection IDs for cipher-collection assignment.
+    /// </summary>
+    internal List<Guid> CollectionIds { get; } = [];
+
+    /// <summary>
+    /// Cipher IDs for downstream reference.
+    /// </summary>
+    internal List<Guid> CipherIds { get; } = [];
+
+    /// <summary>
+    /// Clears all registry lists. Called by <see cref="RecipeExecutor"/> before each pipeline run.
+    /// </summary>
+    internal void Clear()
+    {
+        HardenedOrgUserIds.Clear();
+        UserDigests.Clear();
+        GroupIds.Clear();
+        CollectionIds.Clear();
+        CipherIds.Clear();
+    }
+}
diff --git a/util/Seeder/Pipeline/OrderedStep.cs b/util/Seeder/Pipeline/OrderedStep.cs
new file mode 100644
index 0000000000..381c8c4b63
--- /dev/null
+++ b/util/Seeder/Pipeline/OrderedStep.cs
@@ -0,0 +1,12 @@
+namespace Bit.Seeder.Pipeline;
+
+/// <summary>
+/// Wraps an <see cref="IStep"/> with an order index for keyed DI registration
+/// where GetKeyedServices does not guarantee order.
+/// </summary>
+internal sealed class OrderedStep(IStep inner, int order) : IStep
+{
+    internal int Order { get; } = order;
+
+    public void Execute(SeederContext context) => inner.Execute(context);
+}
diff --git a/util/Seeder/Pipeline/PresetExecutor.cs b/util/Seeder/Pipeline/PresetExecutor.cs
new file mode 100644
index 0000000000..83ee8fea1c
--- /dev/null
+++ b/util/Seeder/Pipeline/PresetExecutor.cs
@@ -0,0 +1,83 @@
+using AutoMapper;
+using Bit.Core.Entities;
+using Bit.Infrastructure.EntityFramework.Repositories;
+using Bit.Seeder.Services;
+using Microsoft.AspNetCore.Identity;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace Bit.Seeder.Pipeline;
+
+/// <summary>
+/// Orchestrates preset-based seeding by coordinating the Pipeline infrastructure.
+/// </summary>
+internal sealed class PresetExecutor(DatabaseContext db, IMapper mapper)
+{
+    /// <summary>
+    /// Executes a preset by registering its recipe, building a service provider, and running all steps.
+    /// </summary>
+    /// <param name="presetName">Name of the embedded preset (e.g., "dunder-mifflin-full")</param>
+    /// <param name="passwordHasher">Password hasher for user creation</param>
+    /// <param name="manglerService">Mangler service for test isolation</param>
+    /// <returns>Execution result with organization ID and entity counts</returns>
+    internal ExecutionResult Execute(
+        string presetName,
+        IPasswordHasher<User> passwordHasher,
+        IManglerService manglerService)
+    {
+        var reader = new SeedReader();
+
+        var services = new ServiceCollection();
+        services.AddSingleton(passwordHasher);
+        services.AddSingleton(manglerService);
+        services.AddSingleton<ISeedReader>(reader);
+        services.AddSingleton(db);
+
+        PresetLoader.RegisterRecipe(presetName, reader, services);
+
+        using var serviceProvider = services.BuildServiceProvider();
+        var committer = new BulkCommitter(db, mapper);
+        var executor = new RecipeExecutor(presetName, serviceProvider, committer);
+
+        return executor.Execute();
+    }
+
+    /// <summary>
+    /// Lists all available embedded presets and fixtures.
+    /// </summary>
+    /// <returns>Available presets grouped by category</returns>
+    internal static AvailableSeeds ListAvailable()
+    {
+        var seedReader = new SeedReader();
+        var all = seedReader.ListAvailable();
+
+        var presets = all.Where(n => n.StartsWith("presets."))
+            .Select(n => n["presets.".Length..])
+            .ToList();
+
+        var fixtures = all.Where(n => !n.StartsWith("presets."))
+            .GroupBy(n => n.Split('.')[0])
+            .ToDictionary(
+                g => g.Key,
+                g => (IReadOnlyList<string>)g.ToList());
+
+        return new AvailableSeeds(presets, fixtures);
+    }
+}
+
+/// <summary>
+/// Result of pipeline execution with organization ID and entity counts.
+/// </summary>
+internal record ExecutionResult(
+    Guid OrganizationId,
+    string? OwnerEmail,
+    int UsersCount,
+    int GroupsCount,
+    int CollectionsCount,
+    int CiphersCount);
+
+/// <summary>
+/// Available presets and fixtures grouped by category.
+/// </summary>
+internal record AvailableSeeds(
+    IReadOnlyList<string> Presets,
+    IReadOnlyDictionary<string, IReadOnlyList<string>> Fixtures);
diff --git a/util/Seeder/Pipeline/PresetLoader.cs b/util/Seeder/Pipeline/PresetLoader.cs
new file mode 100644
index 0000000000..900644e870
--- /dev/null
+++ b/util/Seeder/Pipeline/PresetLoader.cs
@@ -0,0 +1,102 @@
+using Bit.Seeder.Models;
+using Bit.Seeder.Services;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace Bit.Seeder.Pipeline;
+
+/// <summary>
+/// Loads preset fixtures and registers them as recipes on <see cref="IServiceCollection"/>.
+/// </summary>
+internal static class PresetLoader
+{
+    /// <summary>
+    /// Loads a preset from embedded fixtures and registers its steps as a recipe.
+    /// </summary>
+    /// <param name="presetName">Preset name without extension (e.g., "dunder-mifflin-full")</param>
+    /// <param name="reader">Service for reading embedded seed JSON files</param>
+    /// <param name="services">The service collection to register steps in</param>
+    /// <exception cref="InvalidOperationException">Thrown when preset lacks organization configuration</exception>
+    internal static void RegisterRecipe(string presetName, ISeedReader reader, IServiceCollection services)
+    {
+        var preset = reader.Read<SeedPreset>($"presets.{presetName}");
+
+        if (preset.Organization is null)
+        {
+            throw new InvalidOperationException(
+                $"Preset '{presetName}' must specify an organization.");
+        }
+
+        BuildRecipe(presetName, preset, reader, services);
+    }
+
+    /// <summary>
+    /// Builds a recipe from preset configuration, resolving fixtures and generation counts.
+    /// </summary>
+    /// <remarks>
+    /// Resolution order: Org → Owner → Generator → Roster → Users → Groups → Collections → Ciphers
+    /// </remarks>
+    private static void BuildRecipe(string presetName, SeedPreset preset, ISeedReader reader, IServiceCollection services)
+    {
+        var builder = services.AddRecipe(presetName);
+        var org = preset.Organization!;
+
+        // Resolve domain - either from preset or from fixture
+        var domain = org.Domain;
+
+        if (org.Fixture is not null)
+        {
+            builder.UseOrganization(org.Fixture);
+
+            // If using a fixture and domain not explicitly provided, read it from the fixture
+            if (domain is null)
+            {
+                var orgFixture = reader.Read<SeedOrganization>($"organizations.{org.Fixture}");
+                domain = orgFixture.Domain;
+            }
+        }
+        else if (org.Name is not null && org.Domain is not null)
+        {
+            builder.CreateOrganization(org.Name, org.Domain, org.Seats);
+            domain = org.Domain;
+        }
+
+        builder.AddOwner();
+
+        // Generator requires a domain and is only needed for generated ciphers
+        if (domain is not null && preset.Ciphers?.Count > 0)
+        {
+            builder.WithGenerator(domain);
+        }
+
+        if (preset.Roster?.Fixture is not null)
+        {
+            builder.UseRoster(preset.Roster.Fixture);
+        }
+
+        if (preset.Users is not null)
+        {
+            builder.AddUsers(preset.Users.Count, preset.Users.RealisticStatusMix);
+        }
+
+        if (preset.Groups is not null)
+        {
+            builder.AddGroups(preset.Groups.Count);
+        }
+
+        if (preset.Collections is not null)
+        {
+            builder.AddCollections(preset.Collections.Count);
+        }
+
+        if (preset.Ciphers?.Fixture is not null)
+        {
+            builder.UseCiphers(preset.Ciphers.Fixture);
+        }
+        else if (preset.Ciphers is not null && preset.Ciphers.Count > 0)
+        {
+            builder.AddCiphers(preset.Ciphers.Count);
+        }
+
+        builder.Validate();
+    }
+}
diff --git a/util/Seeder/Pipeline/RecipeBuilder.cs b/util/Seeder/Pipeline/RecipeBuilder.cs
new file mode 100644
index 0000000000..bd96517c8a
--- /dev/null
+++ b/util/Seeder/Pipeline/RecipeBuilder.cs
@@ -0,0 +1,71 @@
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.DependencyInjection.Extensions;
+
+namespace Bit.Seeder.Pipeline;
+
+/// <summary>
+/// Fluent API for building seeding pipelines with DI-based step registration and validation.
+/// </summary>
+/// <remarks>
+/// RecipeBuilder wraps <see cref="IServiceCollection"/> and a recipe name.
+/// It tracks step count for deterministic ordering and validation flags for dependency rules.
+/// <strong>Phase Order:</strong> Org → Owner → Generator → Roster → Users → Groups → Collections → Ciphers
+/// </remarks>
+public class RecipeBuilder
+{
+    private int _stepOrder;
+
+    public RecipeBuilder(string name, IServiceCollection services)
+    {
+        Name = name;
+        Services = services;
+    }
+
+    public string Name { get; }
+
+    public IServiceCollection Services { get; }
+
+    internal bool HasOrg { get; set; }
+
+    internal bool HasOwner { get; set; }
+
+    internal bool HasGenerator { get; set; }
+
+    internal bool HasRosterUsers { get; set; }
+
+    internal bool HasGeneratedUsers { get; set; }
+
+    internal bool HasFixtureCiphers { get; set; }
+
+    internal bool HasGeneratedCiphers { get; set; }
+
+    /// <summary>
+    /// Registers a step as a keyed singleton service with preserved ordering.
+    /// </summary>
+    /// <remarks>
+    /// Steps execute in the order they are registered. Callers must register steps
+    /// in the correct phase order: Org, Owner, Generator, Roster, Users, Groups,
+    /// Collections, Ciphers.
+    /// </remarks>
+    /// <param name="factory">Factory function that creates the step from an IServiceProvider</param>
+    /// <returns>This builder for fluent chaining</returns>
+    public RecipeBuilder AddStep(Func<IServiceProvider, IStep> factory)
+    {
+        var order = _stepOrder++;
+        Services.AddKeyedSingleton<IStep>(Name, (sp, _) => new OrderedStep(factory(sp), order));
+        return this;
+    }
+
+    /// <summary>
+    /// Registers a step type as a keyed singleton with preserved ordering.
+    /// </summary>
+    /// <typeparam name="T">The step implementation type</typeparam>
+    /// <returns>This builder for fluent chaining</returns>
+    public RecipeBuilder AddStep<T>() where T : class, IStep
+    {
+        var order = _stepOrder++;
+        Services.AddKeyedSingleton<IStep>(Name, (sp, _) => new OrderedStep(sp.GetRequiredService<T>(), order));
+        Services.TryAddSingleton<T>();
+        return this;
+    }
+}
diff --git a/util/Seeder/Pipeline/RecipeBuilderExtensions.cs b/util/Seeder/Pipeline/RecipeBuilderExtensions.cs
new file mode 100644
index 0000000000..555c0cd3d5
--- /dev/null
+++ b/util/Seeder/Pipeline/RecipeBuilderExtensions.cs
@@ -0,0 +1,240 @@
+using Bit.Core.Vault.Enums;
+using Bit.Seeder.Data.Distributions;
+using Bit.Seeder.Data.Enums;
+using Bit.Seeder.Steps;
+
+namespace Bit.Seeder.Pipeline;
+
+/// <summary>
+/// Step registration extension methods for <see cref="RecipeBuilder"/>.
+/// Each method validates constraints, sets validation flags, and registers the step via DI.
+/// </summary>
+public static class RecipeBuilderExtensions
+{
+    /// <summary>
+    /// Use an organization from embedded fixtures.
+    /// </summary>
+    /// <param name="builder">The recipe builder</param>
+    /// <param name="fixture">Organization fixture name without extension</param>
+    /// <returns>The builder for fluent chaining</returns>
+    public static RecipeBuilder UseOrganization(this RecipeBuilder builder, string fixture)
+    {
+        builder.HasOrg = true;
+        builder.AddStep(_ => CreateOrganizationStep.FromFixture(fixture));
+        return builder;
+    }
+
+    /// <summary>
+    /// Create an organization inline with specified parameters.
+    /// </summary>
+    /// <param name="builder">The recipe builder</param>
+    /// <param name="name">Organization display name</param>
+    /// <param name="domain">Organization domain (used for email generation)</param>
+    /// <param name="seats">Number of user seats</param>
+    /// <returns>The builder for fluent chaining</returns>
+    public static RecipeBuilder CreateOrganization(this RecipeBuilder builder, string name, string domain, int seats)
+    {
+        builder.HasOrg = true;
+        builder.AddStep(_ => CreateOrganizationStep.FromParams(name, domain, seats));
+        return builder;
+    }
+
+    /// <summary>
+    /// Add an organization owner user with admin privileges.
+    /// </summary>
+    /// <param name="builder">The recipe builder</param>
+    /// <returns>The builder for fluent chaining</returns>
+    public static RecipeBuilder AddOwner(this RecipeBuilder builder)
+    {
+        builder.HasOwner = true;
+        builder.AddStep(_ => new CreateOwnerStep());
+        return builder;
+    }
+
+    /// <summary>
+    /// Initialize seeded random generator for reproducible test data.
+    /// </summary>
+    /// <param name="builder">The recipe builder</param>
+    /// <param name="domain">Organization domain (used for seeding randomness)</param>
+    /// <param name="seed">Optional explicit seed. If null, domain hash is used.</param>
+    /// <returns>The builder for fluent chaining</returns>
+    public static RecipeBuilder WithGenerator(this RecipeBuilder builder, string domain, int? seed = null)
+    {
+        builder.HasGenerator = true;
+        builder.AddStep(_ => InitGeneratorStep.FromDomain(domain, seed));
+        return builder;
+    }
+
+    /// <summary>
+    /// Use a roster from embedded fixtures (users, groups, collections).
+    /// </summary>
+    /// <param name="builder">The recipe builder</param>
+    /// <param name="fixture">Roster fixture name without extension</param>
+    /// <returns>The builder for fluent chaining</returns>
+    /// <exception cref="InvalidOperationException">Thrown when AddUsers() was already called</exception>
+    public static RecipeBuilder UseRoster(this RecipeBuilder builder, string fixture)
+    {
+        if (builder.HasGeneratedUsers)
+        {
+            throw new InvalidOperationException(
+                "Cannot call UseRoster() after AddUsers(). Choose one user source.");
+        }
+
+        builder.HasRosterUsers = true;
+        builder.AddStep(_ => new CreateRosterStep(fixture));
+        return builder;
+    }
+
+    /// <summary>
+    /// Generate users with seeded random data.
+    /// </summary>
+    /// <param name="builder">The recipe builder</param>
+    /// <param name="count">Number of users to generate</param>
+    /// <param name="realisticStatusMix">If true, includes revoked/invited users; if false, all confirmed</param>
+    /// <returns>The builder for fluent chaining</returns>
+    /// <exception cref="InvalidOperationException">Thrown when UseRoster() was already called</exception>
+    public static RecipeBuilder AddUsers(this RecipeBuilder builder, int count, bool realisticStatusMix = false)
+    {
+        if (builder.HasRosterUsers)
+        {
+            throw new InvalidOperationException(
+                "Cannot call AddUsers() after UseRoster(). Choose one user source.");
+        }
+
+        builder.HasGeneratedUsers = true;
+        builder.AddStep(_ => new CreateUsersStep(count, realisticStatusMix));
+        return builder;
+    }
+
+    /// <summary>
+    /// Generate groups with random members from existing users.
+    /// </summary>
+    /// <param name="builder">The recipe builder</param>
+    /// <param name="count">Number of groups to generate</param>
+    /// <returns>The builder for fluent chaining</returns>
+    /// <exception cref="InvalidOperationException">Thrown when no users exist</exception>
+    public static RecipeBuilder AddGroups(this RecipeBuilder builder, int count)
+    {
+        if (!builder.HasRosterUsers && !builder.HasGeneratedUsers)
+        {
+            throw new InvalidOperationException(
+                "Groups require users. Call UseRoster() or AddUsers() first.");
+        }
+
+        builder.AddStep(_ => new CreateGroupsStep(count));
+        return builder;
+    }
+
+    /// <summary>
+    /// Generate collections with random assignments.
+    /// </summary>
+    /// <param name="builder">The recipe builder</param>
+    /// <param name="count">Number of collections to generate</param>
+    /// <returns>The builder for fluent chaining</returns>
+    /// <exception cref="InvalidOperationException">Thrown when no users exist</exception>
+    public static RecipeBuilder AddCollections(this RecipeBuilder builder, int count)
+    {
+        if (!builder.HasRosterUsers && !builder.HasGeneratedUsers)
+        {
+            throw new InvalidOperationException(
+                "Collections require users. Call UseRoster() or AddUsers() first.");
+        }
+
+        builder.AddStep(_ => CreateCollectionsStep.FromCount(count));
+        return builder;
+    }
+
+    /// <summary>
+    /// Generate collections based on organizational structure model.
+    /// </summary>
+    /// <param name="builder">The recipe builder</param>
+    /// <param name="structure">Organizational structure (Traditional, Spotify, Modern)</param>
+    /// <returns>The builder for fluent chaining</returns>
+    /// <exception cref="InvalidOperationException">Thrown when no users exist</exception>
+    public static RecipeBuilder AddCollections(this RecipeBuilder builder, OrgStructureModel structure)
+    {
+        if (!builder.HasRosterUsers && !builder.HasGeneratedUsers)
+        {
+            throw new InvalidOperationException(
+                "Collections require users. Call UseRoster() or AddUsers() first.");
+        }
+
+        builder.AddStep(_ => CreateCollectionsStep.FromStructure(structure));
+        return builder;
+    }
+
+    /// <summary>
+    /// Use ciphers from embedded fixtures.
+    /// </summary>
+    /// <param name="builder">The recipe builder</param>
+    /// <param name="fixture">Cipher fixture name without extension</param>
+    /// <returns>The builder for fluent chaining</returns>
+    /// <exception cref="InvalidOperationException">Thrown when AddCiphers() was already called</exception>
+    public static RecipeBuilder UseCiphers(this RecipeBuilder builder, string fixture)
+    {
+        if (builder.HasGeneratedCiphers)
+        {
+            throw new InvalidOperationException(
+                "Cannot call UseCiphers() after AddCiphers(). Choose one cipher source.");
+        }
+
+        builder.HasFixtureCiphers = true;
+        builder.AddStep(_ => new CreateCiphersStep(fixture));
+        return builder;
+    }
+
+    /// <summary>
+    /// Generate ciphers with configurable type and password strength distributions.
+    /// </summary>
+    /// <param name="builder">The recipe builder</param>
+    /// <param name="count">Number of ciphers to generate</param>
+    /// <param name="typeDist">Distribution of cipher types. Uses realistic defaults if null.</param>
+    /// <param name="pwDist">Distribution of password strengths. Uses realistic defaults if null.</param>
+    /// <returns>The builder for fluent chaining</returns>
+    /// <exception cref="InvalidOperationException">Thrown when UseCiphers() was already called</exception>
+    public static RecipeBuilder AddCiphers(
+        this RecipeBuilder builder,
+        int count,
+        Distribution<CipherType>? typeDist = null,
+        Distribution<PasswordStrength>? pwDist = null)
+    {
+        if (builder.HasFixtureCiphers)
+        {
+            throw new InvalidOperationException(
+                "Cannot call AddCiphers() after UseCiphers(). Choose one cipher source.");
+        }
+
+        builder.HasGeneratedCiphers = true;
+        builder.AddStep(_ => new GenerateCiphersStep(count, typeDist, pwDist));
+        return builder;
+    }
+
+    /// <summary>
+    /// Validates the builder state to ensure all required steps are present and dependencies are met.
+    /// </summary>
+    /// <param name="builder">The recipe builder</param>
+    /// <returns>The builder for fluent chaining</returns>
+    /// <exception cref="InvalidOperationException">Thrown when required steps missing or dependencies violated</exception>
+    public static RecipeBuilder Validate(this RecipeBuilder builder)
+    {
+        if (!builder.HasOrg)
+        {
+            throw new InvalidOperationException(
+                "Organization is required. Call UseOrganization() or CreateOrganization().");
+        }
+
+        if (!builder.HasOwner)
+        {
+            throw new InvalidOperationException(
+                "Owner is required. Call AddOwner().");
+        }
+
+        if (builder.HasGeneratedCiphers && !builder.HasGenerator)
+        {
+            throw new InvalidOperationException(
+                "Generated ciphers require a generator. Call WithGenerator() first.");
+        }
+
+        return builder;
+    }
+}
diff --git a/util/Seeder/Pipeline/RecipeExecutor.cs b/util/Seeder/Pipeline/RecipeExecutor.cs
new file mode 100644
index 0000000000..afeb12aba2
--- /dev/null
+++ b/util/Seeder/Pipeline/RecipeExecutor.cs
@@ -0,0 +1,55 @@
+using Microsoft.Extensions.DependencyInjection;
+
+namespace Bit.Seeder.Pipeline;
+
+/// <summary>
+/// Resolves steps from DI by recipe key and executes them in order.
+/// </summary>
+internal sealed class RecipeExecutor
+{
+    private readonly string _recipeName;
+
+    private readonly IServiceProvider _serviceProvider;
+
+    private readonly BulkCommitter _committer;
+
+    internal RecipeExecutor(string recipeName, IServiceProvider serviceProvider, BulkCommitter committer)
+    {
+        _recipeName = recipeName;
+        _serviceProvider = serviceProvider;
+        _committer = committer;
+    }
+
+    /// <summary>
+    /// Executes the recipe by resolving keyed steps, running them in order, and committing results.
+    /// </summary>
+    /// <remarks>
+    /// Clears the EntityRegistry at the start to ensure a clean slate for each run.
+    /// </remarks>
+    internal ExecutionResult Execute()
+    {
+        var steps = _serviceProvider.GetKeyedServices<IStep>(_recipeName)
+            .OrderBy(s => s is OrderedStep os ? os.Order : int.MaxValue)
+            .ToList();
+
+        var context = new SeederContext(_serviceProvider);
+        context.Registry.Clear();
+
+        foreach (var step in steps)
+        {
+            step.Execute(context);
+        }
+
+        // Capture counts BEFORE committing (commit clears the lists)
+        var result = new ExecutionResult(
+            context.RequireOrgId(),
+            context.Owner?.Email,
+            context.Users.Count,
+            context.Groups.Count,
+            context.Collections.Count,
+            context.Ciphers.Count);
+
+        _committer.Commit(context);
+        return result;
+    }
+}
diff --git a/util/Seeder/Pipeline/RecipeServiceCollectionExtensions.cs b/util/Seeder/Pipeline/RecipeServiceCollectionExtensions.cs
new file mode 100644
index 0000000000..39db193495
--- /dev/null
+++ b/util/Seeder/Pipeline/RecipeServiceCollectionExtensions.cs
@@ -0,0 +1,20 @@
+using Microsoft.Extensions.DependencyInjection;
+
+namespace Bit.Seeder.Pipeline;
+
+/// <summary>
+/// Entry point extension method for registering recipes on <see cref="IServiceCollection"/>.
+/// </summary>
+public static class RecipeServiceCollectionExtensions
+{
+    /// <summary>
+    /// Creates a new <see cref="RecipeBuilder"/> for registering steps as keyed services.
+    /// </summary>
+    /// <param name="services">The service collection to register steps in</param>
+    /// <param name="recipeName">Unique name used as the keyed service key</param>
+    /// <returns>A new RecipeBuilder for fluent step registration</returns>
+    public static RecipeBuilder AddRecipe(this IServiceCollection services, string recipeName)
+    {
+        return new RecipeBuilder(recipeName, services);
+    }
+}
diff --git a/util/Seeder/Pipeline/SeederContext.cs b/util/Seeder/Pipeline/SeederContext.cs
new file mode 100644
index 0000000000..b27290e031
--- /dev/null
+++ b/util/Seeder/Pipeline/SeederContext.cs
@@ -0,0 +1,93 @@
+using Bit.Core.AdminConsole.Entities;
+using Bit.Core.Entities;
+using Bit.Core.Vault.Entities;
+using Bit.RustSDK;
+using Bit.Seeder.Data;
+
+namespace Bit.Seeder.Pipeline;
+
+/// <summary>
+/// Shared mutable state bag passed through every <see cref="IStep"/> in a pipeline run.
+/// WARNING: This class is NOT thread-safe. Each pipeline execution must use its own context instance.
+/// Do not share a context instance between concurrent pipeline runs.
+/// </summary>
+/// <remarks>
+/// <para>
+/// Steps resolve services from <see cref="Services"/> instead of accessing fixed properties.
+/// Use the convenience extension methods in <see cref="SeederContextExtensions"/> for common services.
+/// </para>
+/// <para>
+/// <strong>Context Lifecycle:</strong>
+/// <list type="number">
+/// <item><description>Create fresh context for each pipeline run</description></item>
+/// <item><description>Pass to RecipeExecutor.Execute()</description></item>
+/// <item><description>Steps mutate context progressively</description></item>
+/// <item><description>BulkCommitter flushes entity lists to database</description></item>
+/// <item><description>Return org ID from context</description></item>
+/// <item><description>Discard context (do not reuse)</description></item>
+/// </list>
+/// </para>
+/// <para>
+/// Use the <c>Require*()</c> methods instead of accessing nullable properties directly —
+/// they throw with step-ordering guidance if a prerequisite step hasn't run yet.
+/// </para>
+/// </remarks>
+/// <param name="services">
+/// Service provider for resolving dependencies. Steps access services via
+/// <see cref="SeederContextExtensions"/> convenience methods.
+/// </param>
+/// <seealso cref="EntityRegistry"/>
+/// <seealso cref="BulkCommitter"/>
+public sealed class SeederContext(IServiceProvider services)
+{
+    internal IServiceProvider Services { get; } = services;
+
+    internal Organization? Organization { get; set; }
+
+    internal OrganizationKeys? OrgKeys { get; set; }
+
+    internal string? Domain { get; set; }
+
+    internal User? Owner { get; set; }
+
+    internal OrganizationUser? OwnerOrgUser { get; set; }
+
+    internal List<Organization> Organizations { get; } = [];
+
+    internal List<User> Users { get; } = [];
+
+    internal List<OrganizationUser> OrganizationUsers { get; } = [];
+
+    internal List<Cipher> Ciphers { get; } = [];
+
+    internal List<Group> Groups { get; } = [];
+
+    internal List<GroupUser> GroupUsers { get; } = [];
+
+    internal List<Collection> Collections { get; } = [];
+
+    internal List<CollectionUser> CollectionUsers { get; } = [];
+
+    internal List<CollectionGroup> CollectionGroups { get; } = [];
+
+    internal List<CollectionCipher> CollectionCiphers { get; } = [];
+
+    internal EntityRegistry Registry { get; } = new();
+
+    internal GeneratorContext? Generator { get; set; }
+
+    internal Organization RequireOrganization() =>
+        Organization ?? throw new InvalidOperationException("Organization not set. Run CreateOrganizationStep first.");
+
+    internal string RequireOrgKey() =>
+        OrgKeys?.Key ?? throw new InvalidOperationException("Organization keys not set. Run CreateOrganizationStep first.");
+
+    internal Guid RequireOrgId() =>
+        Organization?.Id ?? throw new InvalidOperationException("Organization not set. Run CreateOrganizationStep first.");
+
+    internal string RequireDomain() =>
+        Domain ?? throw new InvalidOperationException("Domain not set. Run CreateOrganizationStep first.");
+
+    internal GeneratorContext RequireGenerator() =>
+        Generator ?? throw new InvalidOperationException("Generator not set. Call WithGenerator() / InitGeneratorStep first.");
+}
diff --git a/util/Seeder/Pipeline/SeederContextExtensions.cs b/util/Seeder/Pipeline/SeederContextExtensions.cs
new file mode 100644
index 0000000000..8281dafb01
--- /dev/null
+++ b/util/Seeder/Pipeline/SeederContextExtensions.cs
@@ -0,0 +1,22 @@
+using Bit.Core.Entities;
+using Bit.Seeder.Services;
+using Microsoft.AspNetCore.Identity;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace Bit.Seeder.Pipeline;
+
+/// <summary>
+/// Convenience extension methods for resolving common services from <see cref="SeederContext.Services"/>.
+/// Minimizes churn in step implementations when transitioning from direct property access to DI.
+/// </summary>
+internal static class SeederContextExtensions
+{
+    internal static IPasswordHasher<User> GetPasswordHasher(this SeederContext context) =>
+        context.Services.GetRequiredService<IPasswordHasher<User>>();
+
+    internal static IManglerService GetMangler(this SeederContext context) =>
+        context.Services.GetRequiredService<IManglerService>();
+
+    internal static ISeedReader GetSeedReader(this SeederContext context) =>
+        context.Services.GetRequiredService<ISeedReader>();
+}
diff --git a/util/Seeder/README.md b/util/Seeder/README.md
index b3eeeb42aa..722c970d1c 100644
--- a/util/Seeder/README.md
+++ b/util/Seeder/README.md
@@ -33,6 +33,37 @@ The seeder transforms SDK output to server format before database insertion.
 
 The Seeder is organized around six core patterns, each with a specific responsibility:
 
+#### Pipeline
+
+**Purpose:** Composable architecture for fixture-based and generated seeding.
+
+**When to use:** New bulk operations, especially with presets. Provides ultimate flexibility.
+
+**Flow**: Preset JSON → PresetLoader → RecipeBuilder → IStep[] → RecipeExecutor → SeederContext → BulkCommitter
+
+**Key actors**:
+
+- **RecipeBuilder**: Fluent API with dependency validation
+- **IStep**: Isolated unit of work (CreateOrganizationStep, CreateUsersStep, etc.)
+- **RecipeExecutor**: Executes steps, captures statistics, commits
+- **PresetExecutor**: Orchestrates preset loading and execution
+- **SeederContext**: Shared mutable state (NOT thread-safe)
+
+**Why this architecture wins**:
+
+- **Infrastructure as Code**: JSON presets define complete scenarios
+- **Mix & Match**: Fixtures + generation in one preset
+- **Extensible**: Add entity types via new IStep implementations
+- **Future-ready**: Supports custom DSLs on top of RecipeBuilder
+
+**Phase order**: Org → Owner → Generator → Roster → Users → Groups → Collections → Ciphers
+
+**Naming**: `{Purpose}Step` classes implementing `IStep`
+
+**Files**: `Pipeline/` folder
+
+---
+
 #### Factories
 
 **Purpose:** Create individual domain entities with cryptographically correct encrypted data.
diff --git a/util/Seeder/Recipes/CollectionsRecipe.cs b/util/Seeder/Recipes/CollectionsRecipe.cs
index d587dafbb4..73fe0c8822 100644
--- a/util/Seeder/Recipes/CollectionsRecipe.cs
+++ b/util/Seeder/Recipes/CollectionsRecipe.cs
@@ -1,6 +1,7 @@
 using Bit.Core.Enums;
 using Bit.Core.Utilities;
 using Bit.Infrastructure.EntityFramework.Repositories;
+using LinqToDB.Data;
 using LinqToDB.EntityFrameworkCore;
 
 namespace Bit.Seeder.Recipes;
@@ -65,7 +66,7 @@ public class CollectionsRecipe(DatabaseContext db)
 
         if (collectionUsers.Any())
         {
-            db.BulkCopy(collectionUsers);
+            db.BulkCopy(new BulkCopyOptions { TableName = nameof(Core.Entities.CollectionUser) }, collectionUsers);
         }
     }
 
diff --git a/util/Seeder/Recipes/OrganizationFromPresetRecipe.cs b/util/Seeder/Recipes/OrganizationFromPresetRecipe.cs
new file mode 100644
index 0000000000..1a00c7307c
--- /dev/null
+++ b/util/Seeder/Recipes/OrganizationFromPresetRecipe.cs
@@ -0,0 +1,72 @@
+using AutoMapper;
+using Bit.Core.Entities;
+using Bit.Infrastructure.EntityFramework.Repositories;
+using Bit.Seeder.Pipeline;
+using Bit.Seeder.Services;
+using Microsoft.AspNetCore.Identity;
+
+namespace Bit.Seeder.Recipes;
+
+/// <summary>
+/// Seeds an organization from an embedded preset.
+/// </summary>
+/// <remarks>
+/// This recipe is a thin facade over the internal Pipeline architecture (PresetExecutor).
+/// All orchestration logic is encapsulated within the Pipeline, keeping this Recipe simple.
+/// The CLI remains "dumb" - it creates this recipe and calls Seed().
+/// </remarks>
+public class OrganizationFromPresetRecipe(
+    DatabaseContext db,
+    IMapper mapper,
+    IPasswordHasher<User> passwordHasher,
+    IManglerService manglerService)
+{
+    private readonly PresetExecutor _executor = new(db, mapper);
+
+    /// <summary>
+    /// Seeds an organization from an embedded preset.
+    /// </summary>
+    /// <param name="presetName">Name of the embedded preset (e.g., "dunder-mifflin-full")</param>
+    /// <returns>The organization ID and summary statistics.</returns>
+    public SeedResult Seed(string presetName)
+    {
+        var result = _executor.Execute(presetName, passwordHasher, manglerService);
+
+        return new SeedResult(
+            result.OrganizationId,
+            result.OwnerEmail,
+            result.UsersCount,
+            result.GroupsCount,
+            result.CollectionsCount,
+            result.CiphersCount);
+    }
+
+    /// <summary>
+    /// Lists all available embedded presets and fixtures.
+    /// </summary>
+    /// <returns>Available presets grouped by category.</returns>
+    public static AvailableSeeds ListAvailable()
+    {
+        var internalResult = PresetExecutor.ListAvailable();
+
+        return new AvailableSeeds(internalResult.Presets, internalResult.Fixtures);
+    }
+}
+
+/// <summary>
+/// Result of seeding operation with summary statistics.
+/// </summary>
+public record SeedResult(
+    Guid OrganizationId,
+    string? OwnerEmail,
+    int UsersCount,
+    int GroupsCount,
+    int CollectionsCount,
+    int CiphersCount);
+
+/// <summary>
+/// Available presets and fixtures grouped by category.
+/// </summary>
+public record AvailableSeeds(
+    IReadOnlyList<string> Presets,
+    IReadOnlyDictionary<string, IReadOnlyList<string>> Fixtures);
diff --git a/util/Seeder/Recipes/OrganizationWithVaultRecipe.cs b/util/Seeder/Recipes/OrganizationWithVaultRecipe.cs
index f73a3c7228..1003c5b0c2 100644
--- a/util/Seeder/Recipes/OrganizationWithVaultRecipe.cs
+++ b/util/Seeder/Recipes/OrganizationWithVaultRecipe.cs
@@ -13,6 +13,7 @@ using Bit.Seeder.Data.Static;
 using Bit.Seeder.Factories;
 using Bit.Seeder.Options;
 using Bit.Seeder.Services;
+using LinqToDB.Data;
 using LinqToDB.EntityFrameworkCore;
 using Microsoft.AspNetCore.Identity;
 using EfFolder = Bit.Infrastructure.EntityFramework.Vault.Models.Folder;
@@ -158,7 +159,7 @@ public class OrganizationWithVaultRecipe(
                             manage: j == 0));
                 })
                 .ToList();
-            db.BulkCopy(collectionUsers);
+            db.BulkCopy(new BulkCopyOptions { TableName = nameof(CollectionUser) }, collectionUsers);
         }
 
         return collections.Select(c => c.Id).ToList();
diff --git a/util/Seeder/Seeder.csproj b/util/Seeder/Seeder.csproj
index 1551eaba6c..1988c7d393 100644
--- a/util/Seeder/Seeder.csproj
+++ b/util/Seeder/Seeder.csproj
@@ -27,6 +27,11 @@
     <Compile Remove="..\..\Program.cs" />
   </ItemGroup>
 
+  <!-- Embed seed data JSON files as assembly resources -->
+  <ItemGroup>
+    <EmbeddedResource Include="Seeds\fixtures\**\*.json" />
+  </ItemGroup>
+
   <!-- Allow integration tests to access internal seeders for validation -->
   <ItemGroup>
     <InternalsVisibleTo Include="SeederApi.IntegrationTest" />
diff --git a/util/Seeder/Seeds/README.md b/util/Seeder/Seeds/README.md
new file mode 100644
index 0000000000..23a2c7a8f0
--- /dev/null
+++ b/util/Seeder/Seeds/README.md
@@ -0,0 +1,149 @@
+# Seeds
+
+Hand-crafted JSON fixtures for Bitwarden Seeder test data.
+
+## Quick Start
+
+1. Copy template from `templates/` to appropriate `fixtures/` subfolder
+2. Edit JSON (your editor validates against `$schema` automatically)
+3. Build to verify: `dotnet build util/Seeder/Seeder.csproj`
+
+## File Structure
+
+```
+Seeds/
+├── fixtures/           Your seed data goes here
+│   ├── ciphers/        Vault items (logins, cards, identities, notes)
+│   ├── organizations/  Organization definitions
+│   ├── rosters/        Users, groups, collections, permissions
+│   └── presets/        Complete seeding scenarios
+├── schemas/            JSON Schema validation (auto-checked by editors)
+├── templates/          Starter files - copy these
+│   └── CONTRIBUTING.md Detailed guide for contributors
+└── README.md           This file
+```
+
+## Fixtures Overview
+
+### Ciphers
+
+Vault items - logins, cards, identities, secure notes.
+
+| Type         | Required Object | Description                |
+| ------------ | --------------- | -------------------------- |
+| `login`      | `login`         | Website credentials + URIs |
+| `card`       | `card`          | Payment card details       |
+| `identity`   | `identity`      | Personal identity info     |
+| `secureNote` | —               | Uses `notes` field only    |
+
+**Example** (`fixtures/ciphers/banking-logins.json`):
+
+```json
+{
+  "$schema": "../../schemas/cipher.schema.json",
+  "items": [
+    {
+      "type": "login",
+      "name": "Chase Bank",
+      "login": {
+        "username": "myuser",
+        "password": "MyP@ssw0rd",
+        "uris": [{ "uri": "https://chase.com", "match": "domain" }]
+      }
+    }
+  ]
+}
+```
+
+### Organizations
+
+Organization definitions with name, domain, and seat count.
+
+```json
+{
+  "$schema": "../../schemas/organization.schema.json",
+  "name": "Acme Corp",
+  "domain": "acme.com",
+  "seats": 100
+}
+```
+
+### Rosters
+
+Complete user/group/collection structures with permissions. User emails auto-generated as `firstName.lastName@domain`.
+
+**User roles**: `owner`, `admin`, `user`, `custom`
+
+**Collection permissions**: `readOnly`, `hidePasswords`, `manage`
+
+See `rosters/dunder-mifflin.json` for a complete 58-user example.
+
+### Presets
+
+Combine organization, roster, and ciphers into complete scenarios.
+
+**From fixtures**:
+
+```json
+{
+  "$schema": "../../schemas/preset.schema.json",
+  "organization": { "fixture": "acme-corp" },
+  "roster": { "fixture": "acme-roster" },
+  "ciphers": { "fixture": "banking-logins" }
+}
+```
+
+**Mixed approach**:
+
+```json
+{
+  "organization": { "fixture": "acme-corp" },
+  "users": { "count": 50 },
+  "ciphers": { "count": 500 }
+}
+```
+
+## Validation
+
+Modern editors validate against `$schema` automatically - errors appear as red squiggles.
+
+Build errors catch schema violations:
+
+```bash
+dotnet build util/Seeder/Seeder.csproj
+```
+
+## Testing
+
+Add integration test in `test/SeederApi.IntegrationTest/SeedReaderTests.cs`:
+
+```csharp
+[Fact]
+public void Read_YourFixture_Success()
+{
+    var result = _reader.Read<SeedFile>("ciphers.your-fixture");
+    Assert.NotEmpty(result.Items);
+}
+```
+
+## Naming Conventions
+
+| Element     | Pattern            | Example                  |
+| ----------- | ------------------ | ------------------------ |
+| File names  | kebab-case         | `banking-logins.json`    |
+| Item names  | Title case, unique | `Chase Bank Login`       |
+| User refs   | firstName.lastName | `jane.doe`               |
+| Org domains | Realistic or .test | `acme.com`, `test.local` |
+
+## Security
+
+- Test password: `asdfasdfasdf`
+- Use fictional names/addresses
+- Never commit real passwords or PII
+- Never seed production databases
+
+## Examples
+
+- **Small org**: `presets/dunder-mifflin-full.json` (58 users, realistic structure)
+- **Browser testing**: `ciphers/autofill-testing.json` (18 specialized items)
+- **Real websites**: `ciphers/public-site-logins.json` (90+ website examples)
diff --git a/util/Seeder/Seeds/fixtures/ciphers/autofill-testing.json b/util/Seeder/Seeds/fixtures/ciphers/autofill-testing.json
new file mode 100644
index 0000000000..06f6dc0c5b
--- /dev/null
+++ b/util/Seeder/Seeds/fixtures/ciphers/autofill-testing.json
@@ -0,0 +1,214 @@
+{
+  "$schema": "../../schemas/cipher.schema.json",
+  "items": [
+    {
+      "type": "login",
+      "name": "Simple Login",
+      "login": {
+        "username": "bwplaywright",
+        "password": "fakeBasicFormPassword",
+        "uris": [
+          { "uri": "https://localhost/forms/login/simple", "match": "startsWith" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Iframe Login",
+      "login": {
+        "username": "bwplaywright",
+        "password": "fakeIframeBasicFormPassword",
+        "uris": [
+          { "uri": "https://localhost/forms/login/iframe-login", "match": "startsWith" },
+          { "uri": "https://localhost/login-page-bare", "match": "startsWith" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Sandboxed Iframe Login",
+      "login": {
+        "username": "bwplaywright",
+        "password": "fakeSandboxedIframeBasicFormPassword",
+        "uris": [
+          { "uri": "https://localhost/forms/login/iframe-sandboxed-login", "match": "startsWith" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Bare Inputs Login",
+      "login": {
+        "username": "bwplaywright",
+        "password": "fakeBareInputsPassword",
+        "uris": [
+          { "uri": "https://localhost/forms/login/bare-inputs-login", "match": "startsWith" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Hidden Login",
+      "login": {
+        "username": "bwplaywright",
+        "password": "fakeHiddenFormPassword",
+        "uris": [
+          { "uri": "https://localhost/forms/login/hidden-login", "match": "startsWith" }
+        ]
+      },
+      "fields": [
+        { "name": "email", "value": "bwplaywright@example.com", "type": "text" }
+      ]
+    },
+    {
+      "type": "login",
+      "name": "Input Constraints Login",
+      "login": {
+        "username": "bwplaywright@example.com",
+        "password": "123456",
+        "uris": [
+          { "uri": "https://localhost/forms/login/input-constraints-login", "match": "startsWith" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Login Honeypot",
+      "login": {
+        "username": "bwplaywright",
+        "password": "fakeLoginHoneypotPassword",
+        "uris": [
+          { "uri": "https://localhost/forms/login/login-honeypot", "match": "startsWith" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Multi-Step Email Username Login",
+      "login": {
+        "username": "bwplaywright",
+        "password": "fakeMultiStepPassword",
+        "uris": [
+          { "uri": "https://localhost/forms/multi-step/email-username-login", "match": "startsWith" }
+        ]
+      },
+      "fields": [
+        { "name": "email", "value": "bwplaywright@example.com", "type": "text" }
+      ]
+    },
+    {
+      "type": "login",
+      "name": "Security Code Multi Input",
+      "login": {
+        "uris": [
+          { "uri": "https://localhost/forms/login/security-code-multi-input", "match": "startsWith" }
+        ],
+        "totp": "ABCD EFGH IJKL MNOPsecurity-code-multi-input"
+      }
+    },
+    {
+      "type": "login",
+      "name": "Shadow Root Inputs",
+      "login": {
+        "username": "bwplaywright",
+        "password": "fakeShadowRootInputsPassword",
+        "uris": [
+          { "uri": "https://localhost/forms/login/shadow-root-inputs", "match": "startsWith" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Create Account",
+      "login": {
+        "username": "bwplaywright@example.com",
+        "password": "fakeCreateAccountPagePassword",
+        "uris": [
+          { "uri": "https://localhost/forms/create/create-account", "match": "startsWith" }
+        ]
+      }
+    },
+    {
+      "type": "identity",
+      "name": "NA Address - John Smith",
+      "identity": {
+        "firstName": "John",
+        "middleName": "M",
+        "lastName": "Smith",
+        "address1": "123 Main St",
+        "address2": "Apt 1",
+        "city": "New York",
+        "state": "NY",
+        "postalCode": "10001",
+        "country": "USA"
+      }
+    },
+    {
+      "type": "card",
+      "name": "Visa Test Card",
+      "card": {
+        "cardholderName": "John Smith",
+        "brand": "Visa",
+        "number": "4111111111111111",
+        "expMonth": "12",
+        "expYear": "2025",
+        "code": "123"
+      }
+    },
+    {
+      "type": "login",
+      "name": "Simple Search",
+      "login": {
+        "username": "bwplaywright",
+        "password": "fakeSimpleSearchPassword",
+        "uris": [
+          { "uri": "https://localhost/forms/search/simple-search", "match": "startsWith" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Inline Search",
+      "login": {
+        "username": "bwplaywright",
+        "password": "fakeInlineSearchPassword",
+        "uris": [
+          { "uri": "https://localhost/forms/search/inline-search", "match": "startsWith" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Typeless Search",
+      "login": {
+        "username": "bwplaywright",
+        "password": "fakeTypelessSearchPassword",
+        "uris": [
+          { "uri": "https://localhost/forms/search/typeless-search", "match": "startsWith" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Update Email",
+      "login": {
+        "username": "bwplaywright@example.com",
+        "password": "fakeUpdateEmailPagePassword",
+        "uris": [
+          { "uri": "https://localhost/forms/update/update-email", "match": "startsWith" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Update Password",
+      "login": {
+        "username": "bwplaywright@example.com",
+        "password": "fakeUpdatePasswordPagePassword",
+        "uris": [
+          { "uri": "https://localhost/forms/update/update-password", "match": "startsWith" }
+        ]
+      }
+    }
+  ]
+}
diff --git a/util/Seeder/Seeds/fixtures/ciphers/public-site-logins.json b/util/Seeder/Seeds/fixtures/ciphers/public-site-logins.json
new file mode 100644
index 0000000000..96eda999b6
--- /dev/null
+++ b/util/Seeder/Seeds/fixtures/ciphers/public-site-logins.json
@@ -0,0 +1,1035 @@
+{
+  "$schema": "../../schemas/cipher.schema.json",
+  "items": [
+    {
+      "type": "login",
+      "name": "LinkedIn Homepage",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeLinkedInHomepageLoginPassword",
+        "uris": [
+          { "uri": "https://www.linkedin.com/", "match": "exact" },
+          { "uri": "https://www.linkedin.com/?original_referer=", "match": "exact" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "LinkedIn Login",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeLinkedInPassword",
+        "uris": [
+          { "uri": "https://www.linkedin.com/login", "match": "exact" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Samsung",
+      "login": {
+        "username": "testuser@example.com",
+        "uris": [
+          { "uri": "https://account.samsung.com/membership/auth/sign-in" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Zillow",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeZillowPassword",
+        "uris": [
+          { "uri": "https://www.zillow.com" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Character.AI",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeCharacterAIPassword",
+        "uris": [
+          { "uri": "https://beta.character.ai/", "match": "host" },
+          { "uri": "https://character-ai.us.auth0.com", "match": "host" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Indeed",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeIndeedPassword",
+        "uris": [
+          { "uri": "https://secure.indeed.com/auth" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Home Depot",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeHomeDepotPassword",
+        "uris": [
+          { "uri": "https://www.homedepot.com/auth/view/signin" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Daily Mail",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeDailyMailPassword",
+        "uris": [
+          { "uri": "https://www.dailymail.co.uk/registration/login.html" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Google",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeGooglePassword",
+        "uris": [
+          { "uri": "https://accounts.google.com" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Facebook",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeFacebookPassword",
+        "uris": [
+          { "uri": "https://www.facebook.com" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Reddit Login Page",
+      "login": {
+        "username": "bwplaywright",
+        "password": "fakeRedditLoginPagePassword",
+        "uris": [
+          { "uri": "https://www.reddit.com/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Amazon",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeAmazonPassword",
+        "uris": [
+          { "uri": "https://www.amazon.com/gp/sign-in.html" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Twitter",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeTwitterPassword",
+        "uris": [
+          { "uri": "https://twitter.com/login?lang=en" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Yahoo",
+      "login": {
+        "username": "bwplaywright",
+        "password": "fakeYahooPassword",
+        "uris": [
+          { "uri": "https://login.yahoo.com" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Wikipedia",
+      "login": {
+        "username": "bwplaywright",
+        "password": "fakeWikipediaPassword",
+        "uris": [
+          { "uri": "https://en.wikipedia.org/w/index.php?title=Special:UserLogin&returnto=Main+Page" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Instagram",
+      "login": {
+        "username": "bwplaywright",
+        "password": "fakeInstagramPassword",
+        "uris": [
+          { "uri": "https://www.instagram.com/accounts/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Fandom",
+      "login": {
+        "username": "Bwplaywright",
+        "password": "fakeFandomPassword",
+        "uris": [
+          { "uri": "https://auth.fandom.com/signin" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Weather.com",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeWeatherPassword",
+        "uris": [
+          { "uri": "https://weather.com/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Microsoft Live",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeLivePassword",
+        "uris": [
+          { "uri": "https://login.live.com" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Microsoft Online",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeMicrosoftOnlinePassword",
+        "uris": [
+          { "uri": "https://login.microsoftonline.com" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "TikTok",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeTikTokPassword",
+        "uris": [
+          { "uri": "https://www.tiktok.com" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "TikTok Login Page",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeTikTokPassword",
+        "uris": [
+          { "uri": "https://www.tiktok.com/login/phone-or-email/email" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Taboola",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeTaboolaPassword",
+        "uris": [
+          { "uri": "https://authentication.taboola.com" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "CNN",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeCNNPassword",
+        "uris": [
+          { "uri": "https://www.cnn.com/account/log-in" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "eBay",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeEbayPassword",
+        "uris": [
+          { "uri": "https://signin.ebay.com/signin" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Twitch",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeTwitchPassword",
+        "uris": [
+          { "uri": "https://www.twitch.tv" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Walmart",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeWalmartPassword",
+        "uris": [
+          { "uri": "https://www.walmart.com/account/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Quora",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeQuoraPassword",
+        "uris": [
+          { "uri": "https://www.quora.com" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "NY Times",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeNYTimesPassword",
+        "uris": [
+          { "uri": "https://myaccount.nytimes.com/auth/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Fox News",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeFoxNewsPassword",
+        "uris": [
+          { "uri": "https://my.foxnews.com" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "USPS",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeUSPSPassword",
+        "uris": [
+          { "uri": "https://reg.usps.com/entreg/LoginAction_input" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "IMDB",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeIMDBPassword",
+        "uris": [
+          { "uri": "https://www.imdb.com/registration/signin" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "PayPal",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakePaypalPassword",
+        "uris": [
+          { "uri": "https://www.sandbox.paypal.com/signin" }
+        ],
+        "totp": "ABCD EFGH IJKL MNOPpaypal-signin"
+      }
+    },
+    {
+      "type": "login",
+      "name": "Zoom",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeZoomPassword",
+        "uris": [
+          { "uri": "https://zoom.us/signin" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Discord",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeDiscordPassword",
+        "uris": [
+          { "uri": "https://discord.com/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Netflix",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeNetflixPassword",
+        "uris": [
+          { "uri": "https://www.netflix.com/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Etsy",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeEtsyPassword",
+        "uris": [
+          { "uri": "https://www.etsy.com" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Pinterest",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakePinterestPassword",
+        "uris": [
+          { "uri": "https://www.pinterest.com/", "match": "exact" },
+          { "uri": "https://www.pinterest.com/login/", "match": "exact" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "GitHub",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeGithubPassword",
+        "uris": [
+          { "uri": "https://github.com/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "NY Post",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeNYPostPassword",
+        "uris": [
+          { "uri": "https://nypost.com/account/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "AccuWeather",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeAccuweatherPassword",
+        "uris": [
+          { "uri": "https://wwwl.accuweather.com/premium_login.php" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "OpenAI",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeOpenAIPassword",
+        "uris": [
+          { "uri": "https://platform.openai.com/login?launch" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "UPS",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeUPSPassword",
+        "uris": [
+          { "uri": "https://www.ups.com/lasso/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Patreon",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakePatreonPassword",
+        "uris": [
+          { "uri": "https://www.patreon.com/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Imgur",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeImgurPassword",
+        "uris": [
+          { "uri": "https://imgur.com/signin" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "IGN",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeIGNPassword",
+        "uris": [
+          { "uri": "https://ign.com" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "AWS",
+      "login": {
+        "username": "testuser@example.com",
+        "uris": [
+          { "uri": "https://aws.amazon.com" },
+          { "uri": "https://signin.aws.amazon.com" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Roblox",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeRobloxPassword",
+        "uris": [
+          { "uri": "https://www.roblox.com/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Spotify",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeSpotifyPassword",
+        "uris": [
+          { "uri": "https://accounts.spotify.com/en/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Instructure Canvas",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeInstructurePassword",
+        "uris": [
+          { "uri": "https://www.instructure.com/canvas/login/free-for-teacher" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Badgr",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeBadgrPassword",
+        "uris": [
+          { "uri": "https://badgr.com/auth/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Portfolium",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakePortfoliumPassword",
+        "uris": [
+          { "uri": "https://portfolium.com/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Mastery Connect",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeMasteryPassword",
+        "uris": [
+          { "uri": "https://app.masteryconnect.com/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Elevate DS (Kimono Cloud)",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeElevateDSPassword",
+        "uris": [
+          { "uri": "https://identity.us2.kimonocloud.com/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "LearnPlatform",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeLearnPlatformPassword",
+        "uris": [
+          { "uri": "https://app.learnplatform.com/users/sign_in" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Target",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeTargetPassword",
+        "uris": [
+          { "uri": "https://www.target.com/account" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Craigslist",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeCraigsListPassword",
+        "uris": [
+          { "uri": "https://accounts.craigslist.org/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Capital One Widget",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeCapitalOneWidgetPassword",
+        "uris": [
+          { "uri": "https://www.capitalone.com", "match": "host" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Capital One",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeCapitalOnePassword",
+        "uris": [
+          { "uri": "https://verified.capitalone.com/auth/signin", "match": "host" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "FedEx",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeFedExPassword",
+        "uris": [
+          { "uri": "https://www.fedex.com/secure-login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Tumblr",
+      "login": {
+        "username": "testuser@example.com",
+        "uris": [
+          { "uri": "https://www.tumblr.com" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Marca",
+      "login": {
+        "username": "testuser@example.com",
+        "uris": [
+          { "uri": "https://seguro.marca.com/registro/v3/?view=login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Best Buy",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeBestBuyPassword",
+        "uris": [
+          { "uri": "https://www.bestbuy.com/identity/global/signin" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Adobe",
+      "login": {
+        "username": "testuser@example.com",
+        "uris": [
+          { "uri": "https://www.adobe.com" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Hulu",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeHuluPassword",
+        "uris": [
+          { "uri": "https://auth.hulu.com/web/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "BBC",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeBBCPassword",
+        "uris": [
+          { "uri": "https://account.bbc.com/signin" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Steam Community",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeSteamCommunityPassword",
+        "uris": [
+          { "uri": "https://steamcommunity.com/login/home", "match": "exact" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Steam Store",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeSteamStorePassword",
+        "uris": [
+          { "uri": "https://store.steampowered.com/login", "match": "exact" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Lowes",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeLowesPassword",
+        "uris": [
+          { "uri": "https://www.lowes.com/u/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Xfinity",
+      "login": {
+        "username": "testuser@example.com",
+        "uris": [
+          { "uri": "https://login.xfinity.com/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Bezzy PSA",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeBezzyPassword",
+        "uris": [
+          { "uri": "https://www.bezzypsa.com/signin/SIGNIN" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Yelp",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeYelpPassword",
+        "uris": [
+          { "uri": "https://www.yelp.com/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "WordPress",
+      "login": {
+        "username": "testuser@example.com",
+        "uris": [
+          { "uri": "https://wordpress.com/log-in" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Nextdoor",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeNextdoorPassword",
+        "uris": [
+          { "uri": "https://nextdoor.com/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Linktree",
+      "login": {
+        "username": "bwplaywright",
+        "password": "fakeLinktreePassword",
+        "uris": [
+          { "uri": "https://linktr.ee/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Quizlet",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeQuizletPassword",
+        "uris": [
+          { "uri": "https://quizlet.com" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Realtor.com",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeRealtorPassword",
+        "uris": [
+          { "uri": "https://realtor.com" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Canva",
+      "login": {
+        "username": "testuser@example.com",
+        "uris": [
+          { "uri": "https://www.canva.com" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "AT&T",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeATTPassword",
+        "uris": [
+          { "uri": "https://www.att.com/acctmgmt/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Auth0",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeAuth0Password",
+        "uris": [
+          { "uri": "https://auth0.com/api/auth/login", "match": "host" },
+          { "uri": "https://auth0.auth0.com", "match": "host" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Washington Post",
+      "login": {
+        "username": "testuser@example.com",
+        "uris": [
+          { "uri": "https://www.washingtonpost.com/subscribe/signin" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "AOL",
+      "login": {
+        "username": "testuser@example.com",
+        "uris": [
+          { "uri": "https://login.aol.com" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "T-Mobile",
+      "login": {
+        "username": "testuser@example.com",
+        "uris": [
+          { "uri": "https://www.t-mobile.com" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Okta",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeOktaSupportPassword",
+        "uris": [
+          { "uri": "https://login.okta.com/signin" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Bethesda",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeBethesdaPassword",
+        "uris": [
+          { "uri": "https://bethesda.net" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Reddit Inline",
+      "login": {
+        "username": "bwplaywright",
+        "password": "fakeRedditInlineLoginPassword",
+        "uris": [
+          { "uri": "https://www.reddit.com" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Max",
+      "login": {
+        "username": "maxcom_user",
+        "password": "maxcom_password",
+        "uris": [
+          { "uri": "https://auth.max.com/login" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Clear (Brazil)",
+      "login": {
+        "username": "12345678901111",
+        "password": "098765",
+        "uris": [
+          { "uri": "https://login.clear.com.br" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "GameSpot",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeGamespotPassword",
+        "uris": [
+          { "uri": "https://www.gamespot.com/login-signup" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Temu",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeTemuPassword",
+        "uris": [
+          { "uri": "https://temu.com" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Temu Login Page",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeTemuLoginPagePassword",
+        "uris": [
+          { "uri": "https://www.temu.com/login.html" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Apple",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeApplePassword",
+        "uris": [
+          { "uri": "https://www.apple.com" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "Marvel",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeMarvelPassword",
+        "uris": [
+          { "uri": "https://www.marvel.com/signin" }
+        ]
+      }
+    },
+    {
+      "type": "login",
+      "name": "ESPN",
+      "login": {
+        "username": "testuser@example.com",
+        "password": "fakeESPNPassword",
+        "uris": [
+          { "uri": "https://www.espn.com" },
+          { "uri": "https://cdn.registerdisney.go.com/v4/bundle/web/ESPN-ONESITE.WEB" }
+        ]
+      }
+    }
+  ]
+}
diff --git a/util/Seeder/Seeds/fixtures/organizations/dunder-mifflin.json b/util/Seeder/Seeds/fixtures/organizations/dunder-mifflin.json
new file mode 100644
index 0000000000..a442a5e1bd
--- /dev/null
+++ b/util/Seeder/Seeds/fixtures/organizations/dunder-mifflin.json
@@ -0,0 +1,6 @@
+{
+  "$schema": "../../schemas/organization.schema.json",
+  "name": "Dunder Mifflin",
+  "domain": "dundermifflin.com",
+  "seats": 70
+}
diff --git a/util/Seeder/Seeds/fixtures/presets/dunder-mifflin-full.json b/util/Seeder/Seeds/fixtures/presets/dunder-mifflin-full.json
new file mode 100644
index 0000000000..7a6b7b4e62
--- /dev/null
+++ b/util/Seeder/Seeds/fixtures/presets/dunder-mifflin-full.json
@@ -0,0 +1,12 @@
+{
+  "$schema": "../../schemas/preset.schema.json",
+  "organization": {
+    "fixture": "dunder-mifflin"
+  },
+  "roster": {
+    "fixture": "dunder-mifflin"
+  },
+  "ciphers": {
+    "fixture": "autofill-testing"
+  }
+}
diff --git a/util/Seeder/Seeds/fixtures/presets/large-enterprise.json b/util/Seeder/Seeds/fixtures/presets/large-enterprise.json
new file mode 100644
index 0000000000..1936713356
--- /dev/null
+++ b/util/Seeder/Seeds/fixtures/presets/large-enterprise.json
@@ -0,0 +1,21 @@
+{
+  "$schema": "../../schemas/preset.schema.json",
+  "organization": {
+    "name": "Globex Corp",
+    "domain": "globex.com",
+    "seats": 10000
+  },
+  "users": {
+    "count": 5000,
+    "realisticStatusMix": true
+  },
+  "groups": {
+    "count": 100
+  },
+  "collections": {
+    "count": 200
+  },
+  "ciphers": {
+    "count": 50000
+  }
+}
diff --git a/util/Seeder/Seeds/fixtures/rosters/dunder-mifflin.json b/util/Seeder/Seeds/fixtures/rosters/dunder-mifflin.json
new file mode 100644
index 0000000000..938199a7b8
--- /dev/null
+++ b/util/Seeder/Seeds/fixtures/rosters/dunder-mifflin.json
@@ -0,0 +1,310 @@
+{
+  "$schema": "../../schemas/roster.schema.json",
+  "users": [
+    { "firstName": "David", "lastName": "Wallace", "title": "CFO", "role": "owner", "branch": "Corporate", "department": "Executive" },
+    { "firstName": "Jan", "lastName": "Levinson", "title": "VP Northeast Sales", "role": "owner", "branch": "Corporate", "department": "Sales" },
+    { "firstName": "Robert", "lastName": "California", "title": "CEO", "role": "owner", "branch": "Corporate", "department": "Executive" },
+    { "firstName": "Jo", "lastName": "Bennett", "title": "CEO Sabre", "role": "owner", "branch": "Corporate", "department": "Executive" },
+    { "firstName": "Charles", "lastName": "Miner", "title": "VP Northeast", "role": "owner", "branch": "Corporate", "department": "Executive" },
+
+    { "firstName": "Michael", "lastName": "Scott", "title": "Regional Manager", "role": "admin", "branch": "Scranton", "department": "Management" },
+    { "firstName": "Dwight", "lastName": "Schrute", "title": "Assistant to the Regional Manager", "role": "admin", "branch": "Scranton", "department": "Sales" },
+    { "firstName": "Jim", "lastName": "Halpert", "title": "Co-Regional Manager", "role": "admin", "branch": "Scranton", "department": "Sales" },
+    { "firstName": "Andy", "lastName": "Bernard", "title": "Regional Manager", "role": "admin", "branch": "Scranton", "department": "Sales" },
+    { "firstName": "Josh", "lastName": "Porter", "title": "Regional Manager", "role": "admin", "branch": "Stamford", "department": "Management" },
+    { "firstName": "Darryl", "lastName": "Philbin", "title": "Warehouse Foreman", "role": "admin", "branch": "Scranton", "department": "Warehouse" },
+    { "firstName": "Karen", "lastName": "Filippelli", "title": "Regional Manager", "role": "admin", "branch": "Utica", "department": "Sales" },
+    { "firstName": "Deangelo", "lastName": "Vickers", "title": "Regional Manager", "role": "admin", "branch": "Scranton", "department": "Management" },
+    { "firstName": "Gabe", "lastName": "Lewis", "title": "Corporate Coordinator", "role": "admin", "branch": "Scranton", "department": "Management" },
+    { "firstName": "Nellie", "lastName": "Bertram", "title": "Special Projects Manager", "role": "admin", "branch": "Scranton", "department": "Management" },
+    { "firstName": "Ed", "lastName": "Truck", "title": "Regional Manager (Former)", "role": "admin", "branch": "Scranton", "department": "Management" },
+
+    { "firstName": "Stanley", "lastName": "Hudson", "title": "Sales Representative", "branch": "Scranton", "department": "Sales" },
+    { "firstName": "Phyllis", "lastName": "Vance", "title": "Sales Representative", "branch": "Scranton", "department": "Sales" },
+    { "firstName": "Ryan", "lastName": "Howard", "title": "Temp / VP", "branch": "Scranton", "department": "Sales" },
+    { "firstName": "Todd", "lastName": "Packer", "title": "Traveling Salesman", "branch": "Scranton", "department": "Sales" },
+    { "firstName": "Devon", "lastName": "White", "title": "Sales Representative", "branch": "Scranton", "department": "Sales" },
+    { "firstName": "Danny", "lastName": "Cordray", "title": "Traveling Salesman", "branch": "Scranton", "department": "Sales" },
+    { "firstName": "Clark", "lastName": "Green", "title": "Sales Intern", "branch": "Scranton", "department": "Sales" },
+
+    { "firstName": "Angela", "lastName": "Martin", "title": "Senior Accountant", "branch": "Scranton", "department": "Accounting" },
+    { "firstName": "Kevin", "lastName": "Malone", "title": "Accountant", "branch": "Scranton", "department": "Accounting" },
+    { "firstName": "Oscar", "lastName": "Martinez", "title": "Accountant", "branch": "Scranton", "department": "Accounting" },
+
+    { "firstName": "Pam", "lastName": "Beesly", "title": "Receptionist / Office Administrator", "branch": "Scranton", "department": "Administration" },
+    { "firstName": "Erin", "lastName": "Hannon", "title": "Receptionist", "branch": "Scranton", "department": "Administration" },
+    { "firstName": "Cathy", "lastName": "Simms", "title": "Temporary Receptionist", "branch": "Scranton", "department": "Administration" },
+    { "firstName": "Jordan", "lastName": "Garfield", "title": "Executive Assistant", "branch": "Scranton", "department": "Administration" },
+
+    { "firstName": "Toby", "lastName": "Flenderson", "title": "HR Representative", "branch": "Scranton", "department": "Human Resources" },
+    { "firstName": "Holly", "lastName": "Flax", "title": "HR Representative", "branch": "Nashua", "department": "Human Resources" },
+    { "firstName": "Kendall", "lastName": "No-Name", "title": "HR Representative", "branch": "Corporate", "department": "Human Resources" },
+
+    { "firstName": "Kelly", "lastName": "Kapoor", "title": "Customer Service Representative", "branch": "Scranton", "department": "Customer Service" },
+    { "firstName": "Pete", "lastName": "Miller", "title": "Customer Service Representative", "branch": "Scranton", "department": "Customer Service" },
+    { "firstName": "Martin", "lastName": "Nash", "title": "Customer Service Representative", "branch": "Stamford", "department": "Customer Service" },
+
+    { "firstName": "Creed", "lastName": "Bratton", "title": "Quality Assurance Director", "branch": "Scranton", "department": "Quality Assurance" },
+    { "firstName": "Meredith", "lastName": "Palmer", "title": "Supplier Relations", "branch": "Scranton", "department": "Supplier Relations" },
+
+    { "firstName": "Nick", "lastName": "No-Name", "title": "IT Technician", "branch": "Scranton", "department": "IT" },
+
+    { "firstName": "Roy", "lastName": "Anderson", "title": "Warehouse Worker", "branch": "Scranton", "department": "Warehouse" },
+    { "firstName": "Lonny", "lastName": "Collins", "title": "Warehouse Worker", "branch": "Scranton", "department": "Warehouse" },
+    { "firstName": "Madge", "lastName": "Madsen", "title": "Warehouse Worker", "branch": "Scranton", "department": "Warehouse" },
+    { "firstName": "Hidetoshi", "lastName": "Hasagawa", "title": "Warehouse Worker", "branch": "Scranton", "department": "Warehouse" },
+    { "firstName": "Nate", "lastName": "Nickerson", "title": "Warehouse Worker", "branch": "Scranton", "department": "Warehouse" },
+    { "firstName": "Val", "lastName": "Johnson", "title": "Warehouse Worker", "branch": "Scranton", "department": "Warehouse" },
+    { "firstName": "Glenn", "lastName": "No-Name", "title": "Warehouse Worker", "branch": "Scranton", "department": "Warehouse" },
+    { "firstName": "Jerry", "lastName": "DiCanio", "title": "Warehouse Worker", "branch": "Scranton", "department": "Warehouse" },
+    { "firstName": "Mose", "lastName": "Schrute", "title": "Beet Farmer / Temp", "branch": "Scranton", "department": "Warehouse" },
+    { "firstName": "Zeke", "lastName": "Schrute", "title": "Warehouse Worker", "branch": "Scranton", "department": "Warehouse" },
+    { "firstName": "Kenny", "lastName": "Anderson", "title": "Warehouse Worker", "branch": "Scranton", "department": "Warehouse" },
+
+    { "firstName": "Hank", "lastName": "Tate", "title": "Security Guard", "branch": "Scranton", "department": "Security" },
+    { "firstName": "Bob", "lastName": "Vance", "title": "Owner, Vance Refrigeration", "branch": "Scranton", "department": "External" },
+
+    { "firstName": "Hannah", "lastName": "Smoterich-Barr", "title": "Sales Representative", "branch": "Stamford", "department": "Sales" },
+    { "firstName": "Tony", "lastName": "Gardner", "title": "Sales Representative", "branch": "Stamford", "department": "Sales" },
+    { "firstName": "Troy", "lastName": "Underbridge", "title": "Sales Representative", "branch": "Stamford", "department": "Sales" },
+
+    { "firstName": "Luke", "lastName": "Cooper", "title": "Intern", "branch": "Scranton", "department": "Administration" },
+    { "firstName": "Billy", "lastName": "Merchant", "title": "Building Manager", "branch": "Scranton", "department": "Facilities" },
+    { "firstName": "Brian", "lastName": "Wittle", "title": "Boom Operator", "branch": "Scranton", "department": "Documentary" }
+  ],
+  "groups": [
+    {
+      "name": "Scranton",
+      "members": [
+        "michael.scott", "dwight.schrute", "jim.halpert", "andy.bernard", "darryl.philbin",
+        "deangelo.vickers", "gabe.lewis", "nellie.bertram",
+        "stanley.hudson", "phyllis.vance", "ryan.howard", "todd.packer", "devon.white",
+        "danny.cordray", "clark.green",
+        "angela.martin", "kevin.malone", "oscar.martinez",
+        "pam.beesly", "erin.hannon", "cathy.simms", "jordan.garfield",
+        "toby.flenderson",
+        "kelly.kapoor", "pete.miller",
+        "creed.bratton", "meredith.palmer", "nick.no-name",
+        "roy.anderson", "lonny.collins", "madge.madsen", "hidetoshi.hasagawa",
+        "nate.nickerson", "val.johnson", "glenn.no-name", "jerry.dicanio",
+        "mose.schrute", "zeke.schrute", "kenny.anderson",
+        "hank.tate", "bob.vance", "luke.cooper", "billy.merchant"
+      ]
+    },
+    {
+      "name": "Corporate",
+      "members": [
+        "david.wallace", "jan.levinson", "robert.california", "jo.bennett",
+        "charles.miner", "ryan.howard", "kendall.no-name"
+      ]
+    },
+    {
+      "name": "Stamford",
+      "members": [
+        "josh.porter", "karen.filippelli", "andy.bernard", "jim.halpert",
+        "hannah.smoterich-barr", "tony.gardner", "martin.nash", "troy.underbridge"
+      ]
+    },
+    {
+      "name": "Utica",
+      "members": [
+        "karen.filippelli"
+      ]
+    },
+    {
+      "name": "Nashua",
+      "members": [
+        "holly.flax"
+      ]
+    },
+    {
+      "name": "Party Planning Committee",
+      "members": [
+        "angela.martin", "phyllis.vance", "pam.beesly", "meredith.palmer",
+        "karen.filippelli", "kelly.kapoor", "erin.hannon"
+      ]
+    },
+    {
+      "name": "Finer Things Club",
+      "members": [
+        "pam.beesly", "oscar.martinez", "toby.flenderson", "jim.halpert"
+      ]
+    },
+    {
+      "name": "Safety Committee",
+      "members": [
+        "dwight.schrute", "andy.bernard", "darryl.philbin", "toby.flenderson", "hank.tate"
+      ]
+    },
+    {
+      "name": "Call of Duty Crew",
+      "members": [
+        "jim.halpert", "karen.filippelli", "andy.bernard"
+      ]
+    },
+    {
+      "name": "Michael Scott Paper Company",
+      "members": [
+        "michael.scott", "pam.beesly", "ryan.howard"
+      ]
+    },
+    {
+      "name": "Office Basketball",
+      "members": [
+        "michael.scott", "jim.halpert", "ryan.howard", "stanley.hudson",
+        "oscar.martinez", "kevin.malone"
+      ]
+    },
+    {
+      "name": "Warehouse Crew",
+      "members": [
+        "darryl.philbin", "roy.anderson", "lonny.collins", "madge.madsen",
+        "hidetoshi.hasagawa", "val.johnson", "nate.nickerson", "glenn.no-name",
+        "jerry.dicanio", "kenny.anderson", "mose.schrute", "zeke.schrute"
+      ]
+    },
+    {
+      "name": "Office Olympics",
+      "members": [
+        "jim.halpert", "pam.beesly", "kevin.malone", "phyllis.vance",
+        "stanley.hudson", "oscar.martinez", "creed.bratton", "meredith.palmer"
+      ]
+    },
+    {
+      "name": "Search Committee",
+      "members": [
+        "jim.halpert", "toby.flenderson", "gabe.lewis"
+      ]
+    }
+  ],
+  "collections": [
+    {
+      "name": "Departments/Sales",
+      "groups": [
+        { "group": "Scranton" },
+        { "group": "Stamford" }
+      ],
+      "users": [
+        { "user": "jan.levinson", "manage": true },
+        { "user": "michael.scott", "manage": true }
+      ]
+    },
+    {
+      "name": "Departments/Accounting",
+      "groups": [
+        { "group": "Scranton", "readOnly": true }
+      ],
+      "users": [
+        { "user": "angela.martin", "manage": true },
+        { "user": "kevin.malone" },
+        { "user": "oscar.martinez" }
+      ]
+    },
+    {
+      "name": "Departments/Human Resources",
+      "users": [
+        { "user": "toby.flenderson", "manage": true },
+        { "user": "holly.flax", "manage": true },
+        { "user": "kendall.no-name", "manage": true },
+        { "user": "michael.scott", "readOnly": true }
+      ]
+    },
+    {
+      "name": "Departments/Warehouse",
+      "groups": [
+        { "group": "Warehouse Crew" }
+      ],
+      "users": [
+        { "user": "darryl.philbin", "manage": true }
+      ]
+    },
+    {
+      "name": "Departments/Customer Service",
+      "users": [
+        { "user": "kelly.kapoor", "manage": true },
+        { "user": "pete.miller" },
+        { "user": "martin.nash" }
+      ]
+    },
+    {
+      "name": "Departments/Quality Assurance",
+      "users": [
+        { "user": "creed.bratton", "manage": true }
+      ]
+    },
+    {
+      "name": "Departments/Supplier Relations",
+      "users": [
+        { "user": "meredith.palmer", "manage": true }
+      ]
+    },
+    {
+      "name": "Branches/Scranton",
+      "groups": [
+        { "group": "Scranton" }
+      ],
+      "users": [
+        { "user": "michael.scott", "manage": true }
+      ]
+    },
+    {
+      "name": "Branches/Corporate",
+      "groups": [
+        { "group": "Corporate" }
+      ],
+      "users": [
+        { "user": "david.wallace", "manage": true }
+      ]
+    },
+    {
+      "name": "Committees/Party Planning",
+      "groups": [
+        { "group": "Party Planning Committee" }
+      ],
+      "users": [
+        { "user": "angela.martin", "manage": true }
+      ]
+    },
+    {
+      "name": "Committees/Safety",
+      "groups": [
+        { "group": "Safety Committee" }
+      ],
+      "users": [
+        { "user": "dwight.schrute", "manage": true }
+      ]
+    },
+    {
+      "name": "Executive/Reports",
+      "groups": [
+        { "group": "Corporate", "readOnly": true, "hidePasswords": true }
+      ],
+      "users": [
+        { "user": "david.wallace", "manage": true },
+        { "user": "robert.california", "manage": true }
+      ]
+    },
+    {
+      "name": "Executive/Financial",
+      "groups": [
+        { "group": "Corporate", "readOnly": true }
+      ],
+      "users": [
+        { "user": "angela.martin", "manage": true },
+        { "user": "david.wallace", "manage": true }
+      ]
+    },
+    {
+      "name": "Clubs/Finer Things",
+      "groups": [
+        { "group": "Finer Things Club" }
+      ]
+    },
+    {
+      "name": "Clubs/Call of Duty",
+      "groups": [
+        { "group": "Call of Duty Crew" }
+      ]
+    }
+  ]
+}
diff --git a/util/Seeder/Seeds/schemas/cipher.schema.json b/util/Seeder/Seeds/schemas/cipher.schema.json
new file mode 100644
index 0000000000..a094f00acd
--- /dev/null
+++ b/util/Seeder/Seeds/schemas/cipher.schema.json
@@ -0,0 +1,149 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "cipher.schema.json",
+  "title": "Bitwarden Cipher Seed File",
+  "description": "Defines vault items (logins, cards, identities) for the Bitwarden Seeder.",
+  "type": "object",
+  "required": ["items"],
+  "additionalProperties": false,
+  "properties": {
+    "$schema": {
+      "type": "string"
+    },
+    "items": {
+      "type": "array",
+      "minItems": 1,
+      "items": {
+        "$ref": "#/$defs/item"
+      }
+    }
+  },
+  "$defs": {
+    "item": {
+      "type": "object",
+      "required": ["type", "name"],
+      "additionalProperties": false,
+      "properties": {
+        "type": {
+          "type": "string",
+          "enum": ["login", "card", "identity", "secureNote"]
+        },
+        "name": {
+          "type": "string",
+          "minLength": 1
+        },
+        "notes": {
+          "type": "string"
+        },
+        "login": {
+          "$ref": "#/$defs/login"
+        },
+        "card": {
+          "$ref": "#/$defs/card"
+        },
+        "identity": {
+          "$ref": "#/$defs/identity"
+        },
+        "fields": {
+          "type": "array",
+          "items": {
+            "$ref": "#/$defs/field"
+          }
+        }
+      },
+      "allOf": [
+        {
+          "if": { "properties": { "type": { "const": "login" } } },
+          "then": { "required": ["login"] }
+        },
+        {
+          "if": { "properties": { "type": { "const": "card" } } },
+          "then": { "required": ["card"] }
+        },
+        {
+          "if": { "properties": { "type": { "const": "identity" } } },
+          "then": { "required": ["identity"] }
+        }
+      ]
+    },
+    "login": {
+      "type": "object",
+      "additionalProperties": false,
+      "properties": {
+        "username": { "type": "string" },
+        "password": { "type": "string" },
+        "totp": { "type": "string" },
+        "uris": {
+          "type": "array",
+          "items": {
+            "$ref": "#/$defs/loginUri"
+          }
+        }
+      }
+    },
+    "loginUri": {
+      "type": "object",
+      "required": ["uri"],
+      "additionalProperties": false,
+      "properties": {
+        "uri": {
+          "type": "string",
+          "minLength": 1
+        },
+        "match": {
+          "type": "string",
+          "enum": ["domain", "host", "startsWith", "exact", "regex", "never"],
+          "default": "domain"
+        }
+      }
+    },
+    "card": {
+      "type": "object",
+      "additionalProperties": false,
+      "properties": {
+        "cardholderName": { "type": "string" },
+        "brand": { "type": "string" },
+        "number": { "type": "string" },
+        "expMonth": { "type": "string" },
+        "expYear": { "type": "string" },
+        "code": { "type": "string" }
+      }
+    },
+    "identity": {
+      "type": "object",
+      "additionalProperties": false,
+      "properties": {
+        "firstName": { "type": "string" },
+        "middleName": { "type": "string" },
+        "lastName": { "type": "string" },
+        "address1": { "type": "string" },
+        "address2": { "type": "string" },
+        "address3": { "type": "string" },
+        "city": { "type": "string" },
+        "state": { "type": "string" },
+        "postalCode": { "type": "string" },
+        "country": { "type": "string" },
+        "company": { "type": "string" },
+        "email": { "type": "string" },
+        "phone": { "type": "string" },
+        "ssn": { "type": "string" },
+        "username": { "type": "string" },
+        "passportNumber": { "type": "string" },
+        "licenseNumber": { "type": "string" }
+      }
+    },
+    "field": {
+      "type": "object",
+      "additionalProperties": false,
+      "properties": {
+        "name": { "type": "string" },
+        "value": { "type": "string" },
+        "type": {
+          "type": "string",
+          "enum": ["text", "hidden", "boolean", "linked"],
+          "default": "text"
+        }
+      }
+    }
+  }
+}
diff --git a/util/Seeder/Seeds/schemas/organization.schema.json b/util/Seeder/Seeds/schemas/organization.schema.json
new file mode 100644
index 0000000000..ac4abcb70b
--- /dev/null
+++ b/util/Seeder/Seeds/schemas/organization.schema.json
@@ -0,0 +1,30 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "organization.schema.json",
+  "title": "Bitwarden Organization Seed File",
+  "description": "Defines an organization for the Bitwarden Seeder.",
+  "type": "object",
+  "required": ["name", "domain"],
+  "additionalProperties": false,
+  "properties": {
+    "$schema": {
+      "type": "string"
+    },
+    "name": {
+      "type": "string",
+      "minLength": 1,
+      "description": "Display name of the organization."
+    },
+    "domain": {
+      "type": "string",
+      "minLength": 1,
+      "description": "Domain used for billing email and identifier generation."
+    },
+    "seats": {
+      "type": "integer",
+      "minimum": 1,
+      "default": 10,
+      "description": "Number of seats (user slots) in the organization."
+    }
+  }
+}
diff --git a/util/Seeder/Seeds/schemas/preset.schema.json b/util/Seeder/Seeds/schemas/preset.schema.json
new file mode 100644
index 0000000000..e17e827342
--- /dev/null
+++ b/util/Seeder/Seeds/schemas/preset.schema.json
@@ -0,0 +1,110 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "preset.schema.json",
+  "title": "Bitwarden Seeder Preset",
+  "description": "Defines a complete seeding preset that composes organization, users, groups, collections, and ciphers.",
+  "type": "object",
+  "additionalProperties": false,
+  "properties": {
+    "$schema": {
+      "type": "string"
+    },
+    "organization": {
+      "type": "object",
+      "description": "Organization configuration. Use 'fixture' for a named fixture, or 'name'+'domain' for inline creation.",
+      "additionalProperties": false,
+      "properties": {
+        "fixture": {
+          "type": "string",
+          "description": "Name of an organization fixture file (e.g., 'dunder-mifflin')."
+        },
+        "name": {
+          "type": "string",
+          "description": "Organization display name (used with inline creation)."
+        },
+        "domain": {
+          "type": "string",
+          "description": "Organization domain (used with inline creation and generator seeding)."
+        },
+        "seats": {
+          "type": "integer",
+          "minimum": 1,
+          "default": 10,
+          "description": "Number of seats in the organization."
+        }
+      }
+    },
+    "roster": {
+      "type": "object",
+      "description": "Named roster fixture for users, groups, and collections.",
+      "additionalProperties": false,
+      "properties": {
+        "fixture": {
+          "type": "string",
+          "description": "Name of a roster fixture file (e.g., 'dunder-mifflin')."
+        }
+      },
+      "required": ["fixture"]
+    },
+    "users": {
+      "type": "object",
+      "description": "Generate random users.",
+      "additionalProperties": false,
+      "properties": {
+        "count": {
+          "type": "integer",
+          "minimum": 1,
+          "description": "Number of users to generate."
+        },
+        "realisticStatusMix": {
+          "type": "boolean",
+          "default": false,
+          "description": "When true and count >= 10, creates realistic mix: 85% Confirmed, 5% Invited, 5% Accepted, 5% Revoked."
+        }
+      },
+      "required": ["count"]
+    },
+    "groups": {
+      "type": "object",
+      "description": "Generate random groups with round-robin user assignment.",
+      "additionalProperties": false,
+      "properties": {
+        "count": {
+          "type": "integer",
+          "minimum": 1,
+          "description": "Number of groups to generate."
+        }
+      },
+      "required": ["count"]
+    },
+    "collections": {
+      "type": "object",
+      "description": "Generate random collections with user assignments.",
+      "additionalProperties": false,
+      "properties": {
+        "count": {
+          "type": "integer",
+          "minimum": 1,
+          "description": "Number of collections to generate."
+        }
+      },
+      "required": ["count"]
+    },
+    "ciphers": {
+      "type": "object",
+      "description": "Cipher configuration. Use 'fixture' for a named fixture, or 'count' for random generation.",
+      "additionalProperties": false,
+      "properties": {
+        "fixture": {
+          "type": "string",
+          "description": "Name of a cipher fixture file (e.g., 'autofill-testing')."
+        },
+        "count": {
+          "type": "integer",
+          "minimum": 1,
+          "description": "Number of random ciphers to generate."
+        }
+      }
+    }
+  }
+}
diff --git a/util/Seeder/Seeds/schemas/roster.schema.json b/util/Seeder/Seeds/schemas/roster.schema.json
new file mode 100644
index 0000000000..2ae31cb93d
--- /dev/null
+++ b/util/Seeder/Seeds/schemas/roster.schema.json
@@ -0,0 +1,152 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "roster.schema.json",
+  "title": "Bitwarden Roster Seed File",
+  "description": "Defines an organization's people structure: users, groups, and collections with permissions.",
+  "type": "object",
+  "required": ["users"],
+  "additionalProperties": false,
+  "properties": {
+    "$schema": {
+      "type": "string"
+    },
+    "users": {
+      "type": "array",
+      "minItems": 1,
+      "description": "Organization members. Email prefix is derived as firstName.lastName@domain.",
+      "items": { "$ref": "#/$defs/user" }
+    },
+    "groups": {
+      "type": "array",
+      "description": "Groups within the organization.",
+      "items": { "$ref": "#/$defs/group" }
+    },
+    "collections": {
+      "type": "array",
+      "description": "Collections with group and user permission assignments. Use '/' for visual hierarchy.",
+      "items": { "$ref": "#/$defs/collection" }
+    }
+  },
+  "$defs": {
+    "user": {
+      "type": "object",
+      "required": ["firstName", "lastName"],
+      "additionalProperties": false,
+      "properties": {
+        "firstName": {
+          "type": "string",
+          "minLength": 1
+        },
+        "lastName": {
+          "type": "string",
+          "minLength": 1
+        },
+        "title": {
+          "type": "string",
+          "description": "Job title."
+        },
+        "role": {
+          "type": "string",
+          "enum": ["owner", "admin", "user", "custom"],
+          "default": "user",
+          "description": "Organization role."
+        },
+        "branch": {
+          "type": "string",
+          "description": "Branch office for grouping."
+        },
+        "department": {
+          "type": "string",
+          "description": "Department for grouping."
+        }
+      }
+    },
+    "group": {
+      "type": "object",
+      "required": ["name", "members"],
+      "additionalProperties": false,
+      "properties": {
+        "name": {
+          "type": "string",
+          "minLength": 1,
+          "description": "Group display name (not encrypted)."
+        },
+        "members": {
+          "type": "array",
+          "items": {
+            "type": "string"
+          },
+          "description": "Email prefixes (firstName.lastName) of group members."
+        }
+      }
+    },
+    "collection": {
+      "type": "object",
+      "required": ["name"],
+      "additionalProperties": false,
+      "properties": {
+        "name": {
+          "type": "string",
+          "minLength": 1,
+          "description": "Collection name. Use '/' for visual hierarchy (e.g., 'Departments/Sales')."
+        },
+        "groups": {
+          "type": "array",
+          "description": "Group permission assignments.",
+          "items": { "$ref": "#/$defs/collectionGroup" }
+        },
+        "users": {
+          "type": "array",
+          "description": "Direct user permission assignments.",
+          "items": { "$ref": "#/$defs/collectionUser" }
+        }
+      }
+    },
+    "collectionGroup": {
+      "type": "object",
+      "required": ["group"],
+      "additionalProperties": false,
+      "properties": {
+        "group": {
+          "type": "string",
+          "description": "Group name to assign."
+        },
+        "readOnly": {
+          "type": "boolean",
+          "default": false
+        },
+        "hidePasswords": {
+          "type": "boolean",
+          "default": false
+        },
+        "manage": {
+          "type": "boolean",
+          "default": false
+        }
+      }
+    },
+    "collectionUser": {
+      "type": "object",
+      "required": ["user"],
+      "additionalProperties": false,
+      "properties": {
+        "user": {
+          "type": "string",
+          "description": "Email prefix (firstName.lastName) of the user."
+        },
+        "readOnly": {
+          "type": "boolean",
+          "default": false
+        },
+        "hidePasswords": {
+          "type": "boolean",
+          "default": false
+        },
+        "manage": {
+          "type": "boolean",
+          "default": false
+        }
+      }
+    }
+  }
+}
diff --git a/util/Seeder/Seeds/templates/cipher.template.json b/util/Seeder/Seeds/templates/cipher.template.json
new file mode 100644
index 0000000000..ebdc9a68a4
--- /dev/null
+++ b/util/Seeder/Seeds/templates/cipher.template.json
@@ -0,0 +1,50 @@
+{
+  "$schema": "../schemas/cipher.schema.json",
+  "items": [
+    {
+      "type": "login",
+      "name": "Example Login",
+      "login": {
+        "username": "user@example.com",
+        "password": "ChangeMe123!",
+        "uris": [
+          {
+            "uri": "https://example.com/login",
+            "match": "domain"
+          }
+        ]
+      }
+    },
+    {
+      "type": "card",
+      "name": "Example Card",
+      "card": {
+        "cardholderName": "Jane Doe",
+        "brand": "Visa",
+        "number": "4111111111111111",
+        "expMonth": "12",
+        "expYear": "2030",
+        "code": "123"
+      }
+    },
+    {
+      "type": "identity",
+      "name": "Example Identity",
+      "identity": {
+        "firstName": "Jane",
+        "lastName": "Doe",
+        "email": "jane.doe@example.com",
+        "address1": "123 Main St",
+        "city": "Anytown",
+        "state": "CA",
+        "postalCode": "90210",
+        "country": "US"
+      }
+    },
+    {
+      "type": "secureNote",
+      "name": "Example Secure Note",
+      "notes": "This is a secure note with sensitive information."
+    }
+  ]
+}
diff --git a/util/Seeder/Seeds/templates/organization.template.json b/util/Seeder/Seeds/templates/organization.template.json
new file mode 100644
index 0000000000..85f682e23c
--- /dev/null
+++ b/util/Seeder/Seeds/templates/organization.template.json
@@ -0,0 +1,6 @@
+{
+  "$schema": "../schemas/organization.schema.json",
+  "name": "Acme Corporation",
+  "domain": "acme.example.com",
+  "seats": 10
+}
diff --git a/util/Seeder/Seeds/templates/preset.template.json b/util/Seeder/Seeds/templates/preset.template.json
new file mode 100644
index 0000000000..2d0f95e301
--- /dev/null
+++ b/util/Seeder/Seeds/templates/preset.template.json
@@ -0,0 +1,14 @@
+{
+  "$schema": "../schemas/preset.schema.json",
+  "organization": {
+    "name": "Acme Corporation",
+    "domain": "acme.example.com",
+    "seats": 50
+  },
+  "roster": {
+    "fixture": "my-roster-fixture"
+  },
+  "ciphers": {
+    "fixture": "my-cipher-fixture"
+  }
+}
diff --git a/util/Seeder/Seeds/templates/roster.template.json b/util/Seeder/Seeds/templates/roster.template.json
new file mode 100644
index 0000000000..105d2591f9
--- /dev/null
+++ b/util/Seeder/Seeds/templates/roster.template.json
@@ -0,0 +1,77 @@
+{
+  "$schema": "../schemas/roster.schema.json",
+  "users": [
+    {
+      "firstName": "Alice",
+      "lastName": "Admin",
+      "title": "Administrator",
+      "role": "admin",
+      "branch": "Headquarters",
+      "department": "IT"
+    },
+    {
+      "firstName": "Bob",
+      "lastName": "User",
+      "title": "Developer",
+      "role": "user",
+      "branch": "Headquarters",
+      "department": "Engineering"
+    },
+    {
+      "firstName": "Carol",
+      "lastName": "Manager",
+      "title": "Engineering Manager",
+      "role": "admin",
+      "branch": "Headquarters",
+      "department": "Engineering"
+    }
+  ],
+  "groups": [
+    {
+      "name": "Administrators",
+      "members": [
+        "alice.admin",
+        "carol.manager"
+      ]
+    },
+    {
+      "name": "Engineering Team",
+      "members": [
+        "bob.user",
+        "carol.manager"
+      ]
+    }
+  ],
+  "collections": [
+    {
+      "name": "Company Shared",
+      "groups": [
+        {
+          "group": "Administrators",
+          "readOnly": false,
+          "hidePasswords": false,
+          "manage": true
+        }
+      ],
+      "users": [
+        {
+          "user": "alice.admin",
+          "readOnly": false,
+          "hidePasswords": false,
+          "manage": true
+        }
+      ]
+    },
+    {
+      "name": "Engineering/Development",
+      "groups": [
+        {
+          "group": "Engineering Team",
+          "readOnly": false,
+          "hidePasswords": false,
+          "manage": false
+        }
+      ]
+    }
+  ]
+}
diff --git a/util/Seeder/Services/ISeedReader.cs b/util/Seeder/Services/ISeedReader.cs
new file mode 100644
index 0000000000..e944b5711a
--- /dev/null
+++ b/util/Seeder/Services/ISeedReader.cs
@@ -0,0 +1,19 @@
+namespace Bit.Seeder.Services;
+
+/// <summary>
+/// Reads seed data files from embedded JSON resources.
+/// Seeds are pantry ingredients for Recipes, Steps, and Scenes.
+/// </summary>
+public interface ISeedReader
+{
+    /// <summary>
+    /// Reads and deserializes a seed file by name (without extension).
+    /// Names use dot-separated paths: "ciphers.autofill-testing", "organizations.dunder-mifflin"
+    /// </summary>
+    T Read<T>(string seedName);
+
+    /// <summary>
+    /// Lists available seed file names (without extension).
+    /// </summary>
+    IReadOnlyList<string> ListAvailable();
+}
diff --git a/util/Seeder/Services/SeedReader.cs b/util/Seeder/Services/SeedReader.cs
new file mode 100644
index 0000000000..4e90604a3a
--- /dev/null
+++ b/util/Seeder/Services/SeedReader.cs
@@ -0,0 +1,62 @@
+using System.Reflection;
+using System.Text.Json;
+
+namespace Bit.Seeder.Services;
+
+/// <summary>
+/// Reads seed data from embedded JSON resources shipped with the Seeder library.
+/// </summary>
+public sealed class SeedReader : ISeedReader
+{
+    private const string _resourcePrefix = "Bit.Seeder.Seeds.fixtures.";
+    private const string _resourceSuffix = ".json";
+
+    private static readonly Assembly _assembly = typeof(SeedReader).Assembly;
+
+    private static readonly JsonSerializerOptions _jsonOptions = new()
+    {
+        PropertyNameCaseInsensitive = true,
+        ReadCommentHandling = JsonCommentHandling.Skip,
+        AllowTrailingCommas = true
+    };
+
+    public T Read<T>(string seedName)
+    {
+        var resourceName = $"{_resourcePrefix}{seedName}{_resourceSuffix}";
+        using var stream = _assembly.GetManifestResourceStream(resourceName);
+
+        if (stream is null)
+        {
+            var available = string.Join(", ", ListAvailable());
+            throw new InvalidOperationException(
+                $"Seed file '{seedName}' not found. Available seeds: {available}");
+        }
+
+        try
+        {
+            var result = JsonSerializer.Deserialize<T>(stream, _jsonOptions);
+
+            if (result is null)
+            {
+                throw new InvalidOperationException(
+                    $"Seed file '{seedName}' deserialized to null. The JSON may be empty or incompatible with type {typeof(T).Name}.");
+            }
+
+            return result;
+        }
+        catch (JsonException ex)
+        {
+            throw new InvalidOperationException(
+                $"Failed to deserialize seed file '{seedName}' as {typeof(T).Name}: {ex.Message}", ex);
+        }
+    }
+
+    public IReadOnlyList<string> ListAvailable()
+    {
+        return _assembly.GetManifestResourceNames()
+            .Where(n => n.StartsWith(_resourcePrefix) && n.EndsWith(_resourceSuffix))
+            .Select(n => n[_resourcePrefix.Length..^_resourceSuffix.Length])
+            .OrderBy(n => n)
+            .ToList();
+    }
+}
diff --git a/util/Seeder/Steps/CreateCiphersStep.cs b/util/Seeder/Steps/CreateCiphersStep.cs
new file mode 100644
index 0000000000..5f474083b7
--- /dev/null
+++ b/util/Seeder/Steps/CreateCiphersStep.cs
@@ -0,0 +1,64 @@
+using Bit.Core.Entities;
+using Bit.Core.Vault.Entities;
+using Bit.Seeder.Factories;
+using Bit.Seeder.Models;
+using Bit.Seeder.Pipeline;
+
+namespace Bit.Seeder.Steps;
+
+/// <summary>
+/// Loads cipher items from a fixture and creates encrypted cipher entities.
+/// </summary>
+internal sealed class CreateCiphersStep(string fixtureName) : IStep
+{
+    public void Execute(SeederContext context)
+    {
+        var orgId = context.RequireOrgId();
+        var orgKey = context.RequireOrgKey();
+        var seedFile = context.GetSeedReader().Read<SeedFile>($"ciphers.{fixtureName}");
+        var collectionIds = context.Registry.CollectionIds;
+
+        var ciphers = new List<Cipher>();
+        var collectionCiphers = new List<CollectionCipher>();
+
+        for (var i = 0; i < seedFile.Items.Count; i++)
+        {
+            var item = seedFile.Items[i];
+            var cipher = item.Type switch
+            {
+                "login" => LoginCipherSeeder.CreateFromSeed(orgKey, item, organizationId: orgId),
+                "card" => CardCipherSeeder.CreateFromSeed(orgKey, item, organizationId: orgId),
+                "identity" => IdentityCipherSeeder.CreateFromSeed(orgKey, item, organizationId: orgId),
+                "secureNote" => SecureNoteCipherSeeder.CreateFromSeed(orgKey, item, organizationId: orgId),
+                _ => throw new InvalidOperationException($"Unknown cipher type: {item.Type}")
+            };
+
+            ciphers.Add(cipher);
+
+            // Collection assignment (mirrors GenerateCiphersStep logic)
+            if (collectionIds.Count <= 0)
+            {
+                continue;
+            }
+
+            collectionCiphers.Add(new CollectionCipher
+            {
+                CipherId = cipher.Id,
+                CollectionId = collectionIds[i % collectionIds.Count]
+            });
+
+            // Every 3rd cipher gets assigned to an additional collection
+            if (i % 3 == 0 && collectionIds.Count > 1)
+            {
+                collectionCiphers.Add(new CollectionCipher
+                {
+                    CipherId = cipher.Id,
+                    CollectionId = collectionIds[(i + 1) % collectionIds.Count]
+                });
+            }
+        }
+
+        context.Ciphers.AddRange(ciphers);
+        context.CollectionCiphers.AddRange(collectionCiphers);
+    }
+}
diff --git a/util/Seeder/Steps/CreateCollectionsStep.cs b/util/Seeder/Steps/CreateCollectionsStep.cs
new file mode 100644
index 0000000000..a6dd859c6e
--- /dev/null
+++ b/util/Seeder/Steps/CreateCollectionsStep.cs
@@ -0,0 +1,70 @@
+using Bit.Core.Entities;
+using Bit.Seeder.Data.Enums;
+using Bit.Seeder.Data.Static;
+using Bit.Seeder.Factories;
+using Bit.Seeder.Pipeline;
+
+namespace Bit.Seeder.Steps;
+
+internal sealed class CreateCollectionsStep : IStep
+{
+    private readonly int _count;
+    private readonly OrgStructureModel? _structure;
+
+    private CreateCollectionsStep(int count, OrgStructureModel? structure)
+    {
+        _count = count;
+        _structure = structure;
+    }
+
+    internal static CreateCollectionsStep FromCount(int count) => new(count, null);
+
+    internal static CreateCollectionsStep FromStructure(OrgStructureModel structure) => new(0, structure);
+
+    public void Execute(SeederContext context)
+    {
+        var orgId = context.RequireOrgId();
+        var orgKey = context.RequireOrgKey();
+        var hardenedOrgUserIds = context.Registry.HardenedOrgUserIds;
+
+        List<Collection> collections;
+
+        if (_structure.HasValue)
+        {
+            var orgStructure = OrgStructures.GetStructure(_structure.Value);
+            collections = orgStructure.Units
+                .Select(unit => CollectionSeeder.Create(orgId, orgKey, unit.Name))
+                .ToList();
+        }
+        else
+        {
+            collections = Enumerable.Range(0, _count)
+                .Select(i => CollectionSeeder.Create(orgId, orgKey, $"Collection {i + 1}"))
+                .ToList();
+        }
+
+        var collectionIds = collections.Select(c => c.Id).ToList();
+        var collectionUsers = new List<CollectionUser>();
+
+        // User assignment: cycling 1-3 collections per user
+        if (collections.Count > 0 && hardenedOrgUserIds.Count > 0)
+        {
+            foreach (var (orgUserId, userIndex) in hardenedOrgUserIds.Select((id, i) => (id, i)))
+            {
+                var maxAssignments = Math.Min((userIndex % 3) + 1, collections.Count);
+                for (var j = 0; j < maxAssignments; j++)
+                {
+                    collectionUsers.Add(CollectionUserSeeder.Create(
+                        collections[(userIndex + j) % collections.Count].Id,
+                        orgUserId,
+                        readOnly: j > 0,
+                        manage: j == 0));
+                }
+            }
+        }
+
+        context.Collections.AddRange(collections);
+        context.Registry.CollectionIds.AddRange(collectionIds);
+        context.CollectionUsers.AddRange(collectionUsers);
+    }
+}
diff --git a/util/Seeder/Steps/CreateGroupsStep.cs b/util/Seeder/Steps/CreateGroupsStep.cs
new file mode 100644
index 0000000000..7daa621017
--- /dev/null
+++ b/util/Seeder/Steps/CreateGroupsStep.cs
@@ -0,0 +1,39 @@
+using Bit.Core.AdminConsole.Entities;
+using Bit.Seeder.Factories;
+using Bit.Seeder.Pipeline;
+
+namespace Bit.Seeder.Steps;
+
+internal sealed class CreateGroupsStep(int count) : IStep
+{
+    public void Execute(SeederContext context)
+    {
+        var orgId = context.RequireOrgId();
+        var hardenedOrgUserIds = context.Registry.HardenedOrgUserIds;
+
+        var groups = new List<Group>(count);
+        var groupIds = new List<Guid>(count);
+        var groupUsers = new List<GroupUser>();
+
+        for (var i = 0; i < count; i++)
+        {
+            var group = GroupSeeder.Create(orgId, $"Group {i + 1}");
+            groups.Add(group);
+            groupIds.Add(group.Id);
+        }
+
+        // Round-robin user assignment
+        if (groups.Count > 0 && hardenedOrgUserIds.Count > 0)
+        {
+            for (var i = 0; i < hardenedOrgUserIds.Count; i++)
+            {
+                var groupId = groupIds[i % groups.Count];
+                groupUsers.Add(GroupUserSeeder.Create(groupId, hardenedOrgUserIds[i]));
+            }
+        }
+
+        context.Groups.AddRange(groups);
+        context.Registry.GroupIds.AddRange(groupIds);
+        context.GroupUsers.AddRange(groupUsers);
+    }
+}
diff --git a/util/Seeder/Steps/CreateOrganizationStep.cs b/util/Seeder/Steps/CreateOrganizationStep.cs
new file mode 100644
index 0000000000..6db94990b4
--- /dev/null
+++ b/util/Seeder/Steps/CreateOrganizationStep.cs
@@ -0,0 +1,66 @@
+using Bit.RustSDK;
+using Bit.Seeder.Factories;
+using Bit.Seeder.Models;
+using Bit.Seeder.Pipeline;
+
+namespace Bit.Seeder.Steps;
+
+/// <summary>
+/// Creates an organization from a fixture or explicit parameters.
+/// </summary>
+internal sealed class CreateOrganizationStep : IStep
+{
+    private readonly string? _fixtureName;
+    private readonly string? _name;
+    private readonly string? _domain;
+    private readonly int _seats;
+
+    private CreateOrganizationStep(string? fixtureName, string? name, string? domain, int seats)
+    {
+        if (fixtureName is null && (name is null || domain is null))
+        {
+            throw new ArgumentException(
+                "Either fixtureName OR (name AND domain) must be provided.");
+        }
+
+        _fixtureName = fixtureName;
+        _name = name;
+        _domain = domain;
+        _seats = seats;
+    }
+
+    internal static CreateOrganizationStep FromFixture(string fixtureName) =>
+        new(fixtureName, null, null, 0);
+
+    internal static CreateOrganizationStep FromParams(string name, string domain, int seats) =>
+        new(null, name, domain, seats);
+
+    public void Execute(SeederContext context)
+    {
+        string name, domain;
+        int seats;
+
+        if (_fixtureName is not null)
+        {
+            var fixture = context.GetSeedReader().Read<SeedOrganization>($"organizations.{_fixtureName}");
+            name = fixture.Name;
+            domain = fixture.Domain;
+            seats = fixture.Seats;
+        }
+        else
+        {
+            name = _name!;
+            domain = _domain!;
+            seats = _seats;
+        }
+
+        var orgKeys = RustSdkService.GenerateOrganizationKeys();
+        var organization = OrganizationSeeder.Create(name, domain, seats, orgKeys.PublicKey, orgKeys.PrivateKey);
+
+        context.Organization = organization;
+        context.OrgKeys = orgKeys;
+        context.Domain = domain;
+
+        context.Organizations.Add(organization);
+    }
+}
diff --git a/util/Seeder/Steps/CreateOwnerStep.cs b/util/Seeder/Steps/CreateOwnerStep.cs
new file mode 100644
index 0000000000..329f4ffc65
--- /dev/null
+++ b/util/Seeder/Steps/CreateOwnerStep.cs
@@ -0,0 +1,29 @@
+using Bit.Core.Enums;
+using Bit.RustSDK;
+using Bit.Seeder.Factories;
+using Bit.Seeder.Pipeline;
+
+namespace Bit.Seeder.Steps;
+
+/// <summary>
+/// Creates the owner user and links them to the current organization.
+/// </summary>
+internal sealed class CreateOwnerStep : IStep
+{
+    public void Execute(SeederContext context)
+    {
+        var org = context.RequireOrganization();
+        var owner = UserSeeder.Create($"owner@{context.RequireDomain()}", context.GetPasswordHasher(), context.GetMangler());
+
+        var ownerOrgKey = RustSdkService.GenerateUserOrganizationKey(owner.PublicKey!, context.RequireOrgKey());
+        var ownerOrgUser = org.CreateOrganizationUserWithKey(
+            owner, OrganizationUserType.Owner, OrganizationUserStatusType.Confirmed, ownerOrgKey);
+
+        context.Owner = owner;
+        context.OwnerOrgUser = ownerOrgUser;
+
+        context.Users.Add(owner);
+        context.OrganizationUsers.Add(ownerOrgUser);
+        context.Registry.HardenedOrgUserIds.Add(ownerOrgUser.Id);
+    }
+}
diff --git a/util/Seeder/Steps/CreateRosterStep.cs b/util/Seeder/Steps/CreateRosterStep.cs
new file mode 100644
index 0000000000..a231769593
--- /dev/null
+++ b/util/Seeder/Steps/CreateRosterStep.cs
@@ -0,0 +1,129 @@
+using Bit.Core.Enums;
+using Bit.RustSDK;
+using Bit.Seeder.Factories;
+using Bit.Seeder.Models;
+using Bit.Seeder.Pipeline;
+
+namespace Bit.Seeder.Steps;
+
+/// <summary>
+/// Loads a roster fixture and creates users, groups, and collections with permissions.
+/// </summary>
+internal sealed class CreateRosterStep(string fixtureName) : IStep
+{
+    public void Execute(SeederContext context)
+    {
+        var org = context.RequireOrganization();
+        var orgKey = context.RequireOrgKey();
+        var orgId = context.RequireOrgId();
+        var domain = context.RequireDomain();
+        var roster = context.GetSeedReader().Read<SeedRoster>($"rosters.{fixtureName}");
+
+        // Phase 1: Create users — build emailPrefix → orgUserId lookup
+        var userLookup = new Dictionary<string, Guid>(StringComparer.OrdinalIgnoreCase);
+        var emailPrefixes = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
+
+        foreach (var rosterUser in roster.Users)
+        {
+            var emailPrefix = $"{rosterUser.FirstName}.{rosterUser.LastName}".ToLowerInvariant();
+
+            if (!emailPrefixes.Add(emailPrefix))
+            {
+                throw new InvalidOperationException(
+                    $"Duplicate email prefix '{emailPrefix}' in roster '{fixtureName}'. " +
+                    "Each user must have a unique FirstName.LastName combination.");
+            }
+
+            var email = $"{emailPrefix}@{domain}";
+            var mangledEmail = context.GetMangler().Mangle(email);
+            var userKeys = RustSdkService.GenerateUserKeys(mangledEmail, UserSeeder.DefaultPassword);
+            var user = UserSeeder.Create(mangledEmail, context.GetPasswordHasher(), context.GetMangler(), keys: userKeys);
+            var userOrgKey = RustSdkService.GenerateUserOrganizationKey(user.PublicKey!, orgKey);
+            var orgUserType = ParseRole(rosterUser.Role);
+            var orgUser = org.CreateOrganizationUserWithKey(
+                user, orgUserType, OrganizationUserStatusType.Confirmed, userOrgKey);
+
+            userLookup[emailPrefix] = orgUser.Id;
+
+            context.Users.Add(user);
+            context.OrganizationUsers.Add(orgUser);
+            context.Registry.HardenedOrgUserIds.Add(orgUser.Id);
+            context.Registry.UserDigests.Add(
+                new EntityRegistry.UserDigest(user.Id, orgUser.Id, userKeys.Key));
+        }
+
+        // Phase 2: Create groups — build groupName → groupId lookup
+        var groupLookup = new Dictionary<string, Guid>(StringComparer.OrdinalIgnoreCase);
+
+        if (roster.Groups is not null)
+        {
+            foreach (var rosterGroup in roster.Groups)
+            {
+                var group = GroupSeeder.Create(orgId, rosterGroup.Name);
+                groupLookup[rosterGroup.Name] = group.Id;
+                context.Groups.Add(group);
+                context.Registry.GroupIds.Add(group.Id);
+
+                foreach (var memberPrefix in rosterGroup.Members)
+                {
+                    var orgUserId = RequireLookup(userLookup, memberPrefix,
+                        $"Group '{rosterGroup.Name}' references unknown member '{memberPrefix}'.");
+                    context.GroupUsers.Add(GroupUserSeeder.Create(group.Id, orgUserId));
+                }
+            }
+        }
+
+        // Phase 3: Create collections with group/user permission assignments
+        if (roster.Collections is null)
+        {
+            return;
+        }
+
+        foreach (var rosterCollection in roster.Collections)
+        {
+            var collection = CollectionSeeder.Create(orgId, orgKey, rosterCollection.Name);
+            context.Collections.Add(collection);
+            context.Registry.CollectionIds.Add(collection.Id);
+
+            if (rosterCollection.Groups is not null)
+            {
+                foreach (var cg in rosterCollection.Groups)
+                {
+                    var groupId = RequireLookup(groupLookup, cg.Group,
+                        $"Collection '{rosterCollection.Name}' references unknown group '{cg.Group}'.");
+                    context.CollectionGroups.Add(
+                        CollectionGroupSeeder.Create(collection.Id, groupId, cg.ReadOnly, cg.HidePasswords, cg.Manage));
+                }
+            }
+
+            if (rosterCollection.Users is null)
+            {
+                continue;
+            }
+
+            foreach (var cu in rosterCollection.Users)
+            {
+                var orgUserId = RequireLookup(userLookup, cu.User,
+                    $"Collection '{rosterCollection.Name}' references unknown user '{cu.User}'.");
+                context.CollectionUsers.Add(
+                    CollectionUserSeeder.Create(collection.Id, orgUserId, cu.ReadOnly, cu.HidePasswords, cu.Manage));
+            }
+        }
+    }
+
+    private static Guid RequireLookup(Dictionary<string, Guid> lookup, string key, string errorMessage) =>
+        lookup.TryGetValue(key, out var value)
+            ? value
+            : throw new InvalidOperationException(errorMessage);
+
+    private static OrganizationUserType ParseRole(string role) =>
+        role.ToLowerInvariant() switch
+        {
+            "owner" => OrganizationUserType.Owner,
+            "admin" => OrganizationUserType.Admin,
+            "user" => OrganizationUserType.User,
+            "custom" => OrganizationUserType.Custom,
+            _ => throw new InvalidOperationException(
+                $"Unknown role '{role}'. Valid roles: owner, admin, user, custom.")
+        };
+}
diff --git a/util/Seeder/Steps/CreateUsersStep.cs b/util/Seeder/Steps/CreateUsersStep.cs
new file mode 100644
index 0000000000..194840fbb3
--- /dev/null
+++ b/util/Seeder/Steps/CreateUsersStep.cs
@@ -0,0 +1,66 @@
+using Bit.Core.Entities;
+using Bit.Core.Enums;
+using Bit.RustSDK;
+using Bit.Seeder.Data.Distributions;
+using Bit.Seeder.Factories;
+using Bit.Seeder.Pipeline;
+
+namespace Bit.Seeder.Steps;
+
+/// <summary>
+/// Creates member users and links them to the current organization.
+/// When <c>realisticStatusMix</c> is enabled (and count >= 10), users receive a
+/// realistic distribution of Confirmed/Invited/Accepted/Revoked statuses.
+/// </summary>
+internal sealed class CreateUsersStep(int count, bool realisticStatusMix = false) : IStep
+{
+    public void Execute(SeederContext context)
+    {
+        var org = context.RequireOrganization();
+        var orgKey = context.RequireOrgKey();
+        var domain = context.RequireDomain();
+
+        var statusDistribution = realisticStatusMix && count >= 10
+            ? UserStatusDistributions.Realistic
+            : UserStatusDistributions.AllConfirmed;
+
+        var users = new List<User>(count);
+        var organizationUsers = new List<OrganizationUser>(count);
+        var hardenedOrgUserIds = new List<Guid>();
+        var userDigests = new List<EntityRegistry.UserDigest>();
+
+        for (var i = 0; i < count; i++)
+        {
+            var email = $"user{i}@{domain}";
+            var mangledEmail = context.GetMangler().Mangle(email);
+            var userKeys = RustSdkService.GenerateUserKeys(mangledEmail, UserSeeder.DefaultPassword);
+            var user = UserSeeder.Create(mangledEmail, context.GetPasswordHasher(), context.GetMangler(), keys: userKeys);
+
+            var status = statusDistribution.Select(i, count);
+
+            var memberOrgKey = StatusRequiresOrgKey(status)
+                ? RustSdkService.GenerateUserOrganizationKey(user.PublicKey!, orgKey)
+                : null;
+
+            var orgUser = org.CreateOrganizationUserWithKey(
+                user, OrganizationUserType.User, status, memberOrgKey);
+
+            users.Add(user);
+            organizationUsers.Add(orgUser);
+
+            if (status == OrganizationUserStatusType.Confirmed)
+            {
+                hardenedOrgUserIds.Add(orgUser.Id);
+                userDigests.Add(new EntityRegistry.UserDigest(user.Id, orgUser.Id, userKeys.Key));
+            }
+        }
+
+        context.Users.AddRange(users);
+        context.OrganizationUsers.AddRange(organizationUsers);
+        context.Registry.HardenedOrgUserIds.AddRange(hardenedOrgUserIds);
+        context.Registry.UserDigests.AddRange(userDigests);
+    }
+
+    private static bool StatusRequiresOrgKey(OrganizationUserStatusType status) =>
+        status is OrganizationUserStatusType.Confirmed or OrganizationUserStatusType.Revoked;
+}
diff --git a/util/Seeder/Steps/GenerateCiphersStep.cs b/util/Seeder/Steps/GenerateCiphersStep.cs
new file mode 100644
index 0000000000..dc794500b8
--- /dev/null
+++ b/util/Seeder/Steps/GenerateCiphersStep.cs
@@ -0,0 +1,156 @@
+using Bit.Core.Entities;
+using Bit.Core.Vault.Entities;
+using Bit.Core.Vault.Enums;
+using Bit.Seeder.Data;
+using Bit.Seeder.Data.Distributions;
+using Bit.Seeder.Data.Enums;
+using Bit.Seeder.Data.Generators;
+using Bit.Seeder.Data.Static;
+using Bit.Seeder.Factories;
+using Bit.Seeder.Pipeline;
+
+namespace Bit.Seeder.Steps;
+
+/// <summary>
+/// Creates N random cipher entities using the deterministic <see cref="GeneratorContext"/>.
+/// </summary>
+/// <remarks>
+/// Requires <see cref="InitGeneratorStep"/> to have run first. Picks cipher types (login, card,
+/// identity, secureNote, sshKey) from a configurable distribution, delegates to the existing
+/// cipher factories, and assigns each cipher to collections round-robin. Designed for load
+/// testing scenarios where you need thousands of realistic vault items.
+/// </remarks>
+/// <seealso cref="InitGeneratorStep"/>
+/// <seealso cref="CreateCiphersStep"/>
+internal sealed class GenerateCiphersStep(
+    int count,
+    Distribution<CipherType>? typeDist = null,
+    Distribution<PasswordStrength>? pwDist = null) : IStep
+{
+    public void Execute(SeederContext context)
+    {
+        if (count == 0)
+        {
+            return;
+        }
+
+        var generator = context.RequireGenerator();
+
+        var orgId = context.RequireOrgId();
+        var orgKey = context.RequireOrgKey();
+        var collectionIds = context.Registry.CollectionIds;
+        var typeDistribution = typeDist ?? CipherTypeDistributions.Realistic;
+        var passwordDistribution = pwDist ?? PasswordDistributions.Realistic;
+        var companies = Companies.All;
+
+        var ciphers = new List<Cipher>(count);
+        var cipherIds = new List<Guid>(count);
+        var collectionCiphers = new List<CollectionCipher>();
+
+        for (var i = 0; i < count; i++)
+        {
+            var cipherType = typeDistribution.Select(i, count);
+            var cipher = cipherType switch
+            {
+                CipherType.Login => CreateLoginCipher(i, orgId, orgKey, companies, generator, passwordDistribution),
+                CipherType.Card => CreateCardCipher(i, orgId, orgKey, generator),
+                CipherType.Identity => CreateIdentityCipher(i, orgId, orgKey, generator),
+                CipherType.SecureNote => CreateSecureNoteCipher(i, orgId, orgKey, generator),
+                CipherType.SSHKey => CreateSshKeyCipher(i, orgId, orgKey),
+                _ => throw new ArgumentException($"Unsupported cipher type: {cipherType}")
+            };
+
+            ciphers.Add(cipher);
+            cipherIds.Add(cipher.Id);
+
+            // Collection assignment
+            if (collectionIds.Count <= 0)
+            {
+                continue;
+            }
+
+            collectionCiphers.Add(new CollectionCipher
+            {
+                CipherId = cipher.Id,
+                CollectionId = collectionIds[i % collectionIds.Count]
+            });
+
+            // Every 3rd cipher gets assigned to an additional collection
+            if (i % 3 == 0 && collectionIds.Count > 1)
+            {
+                collectionCiphers.Add(new CollectionCipher
+                {
+                    CipherId = cipher.Id,
+                    CollectionId = collectionIds[(i + 1) % collectionIds.Count]
+                });
+            }
+        }
+
+        context.Ciphers.AddRange(ciphers);
+        context.Registry.CipherIds.AddRange(cipherIds);
+        context.CollectionCiphers.AddRange(collectionCiphers);
+    }
+
+    private static Cipher CreateLoginCipher(
+        int index,
+        Guid organizationId,
+        string orgKey,
+        Company[] companies,
+        GeneratorContext generator,
+        Distribution<PasswordStrength> passwordDistribution)
+    {
+        var company = companies[index % companies.Length];
+        return LoginCipherSeeder.Create(
+            orgKey,
+            name: $"{company.Name} ({company.Category})",
+            organizationId: organizationId,
+            username: generator.Username.GenerateByIndex(index, totalHint: generator.CipherCount, domain: company.Domain),
+            password: Passwords.GetPassword(index, generator.CipherCount, passwordDistribution),
+            uri: $"https://{company.Domain}");
+    }
+
+    private static Cipher CreateCardCipher(int index, Guid organizationId, string orgKey, GeneratorContext generator)
+    {
+        var card = generator.Card.GenerateByIndex(index);
+        return CardCipherSeeder.Create(
+            orgKey,
+            name: $"{card.CardholderName}'s {card.Brand}",
+            card: card,
+            organizationId: organizationId);
+    }
+
+    private static Cipher CreateIdentityCipher(int index, Guid organizationId, string orgKey, GeneratorContext generator)
+    {
+        var identity = generator.Identity.GenerateByIndex(index);
+        var name = $"{identity.FirstName} {identity.LastName}";
+        if (!string.IsNullOrEmpty(identity.Company))
+        {
+            name += $" ({identity.Company})";
+        }
+        return IdentityCipherSeeder.Create(
+            orgKey,
+            name: name,
+            identity: identity,
+            organizationId: organizationId);
+    }
+
+    private static Cipher CreateSecureNoteCipher(int index, Guid organizationId, string orgKey, GeneratorContext generator)
+    {
+        var (name, notes) = generator.SecureNote.GenerateByIndex(index);
+        return SecureNoteCipherSeeder.Create(
+            orgKey,
+            name: name,
+            organizationId: organizationId,
+            notes: notes);
+    }
+
+    private static Cipher CreateSshKeyCipher(int index, Guid organizationId, string orgKey)
+    {
+        var sshKey = SshKeyDataGenerator.GenerateByIndex(index);
+        return SshKeyCipherSeeder.Create(
+            orgKey,
+            name: $"SSH Key {index + 1}",
+            sshKey: sshKey,
+            organizationId: organizationId);
+    }
+}
diff --git a/util/Seeder/Steps/InitGeneratorStep.cs b/util/Seeder/Steps/InitGeneratorStep.cs
new file mode 100644
index 0000000000..647121e24d
--- /dev/null
+++ b/util/Seeder/Steps/InitGeneratorStep.cs
@@ -0,0 +1,41 @@
+using Bit.Seeder.Data;
+using Bit.Seeder.Options;
+using Bit.Seeder.Pipeline;
+
+namespace Bit.Seeder.Steps;
+
+/// <summary>
+/// Initializes the deterministic random data engine on <see cref="SeederContext.Generator"/>.
+/// </summary>
+/// <remarks>
+/// Produces no entities itself. Derives a repeatable seed from the domain string (same domain
+/// always yields the same generated data). Downstream steps like <see cref="GenerateCiphersStep"/>
+/// consume the generator for realistic usernames, cards, identities, and notes.
+/// </remarks>
+/// <seealso cref="GeneratorContext"/>
+internal sealed class InitGeneratorStep : IStep
+{
+    private readonly OrganizationVaultOptions _options;
+
+    private InitGeneratorStep(OrganizationVaultOptions options)
+    {
+        _options = options;
+    }
+
+    internal static InitGeneratorStep FromDomain(string domain, int? seed = null)
+    {
+        var options = new OrganizationVaultOptions
+        {
+            Name = domain,
+            Domain = domain,
+            Users = 0,
+            Seed = seed
+        };
+        return new InitGeneratorStep(options);
+    }
+
+    public void Execute(SeederContext context)
+    {
+        context.Generator = GeneratorContext.FromOptions(_options);
+    }
+}