diff --git a/Package.swift b/Package.swift
index b8b5cb4..4029233 100644
--- a/Package.swift
+++ b/Package.swift
@@ -21,7 +21,7 @@ let package = Package(
     .package(url: "https://github.com/vapor/fluent-sqlite-driver.git", from: "4.6.0"),
     // 🍃 An expressive, performant, and extensible templating language built for Swift.
     .package(url: "https://github.com/vapor/leaf.git", from: "4.3.0"),
-    // 🔵 Non-blocking, event-driven networking for Swift. Used for custom executors
+    // 🔵 Non-blocking, event-driven networking for Swift. Used for, custom executors
     .package(url: "https://github.com/apple/swift-nio.git", from: "2.65.0"),
     .package(url: "https://github.com/pointfreeco/swift-dependencies.git", from: "1.6.3"),
     .package(url: "https://github.com/sliemeobn/elementary.git", from: "0.3.2"),
diff --git a/Sources/DatabaseClient/Employees.swift b/Sources/DatabaseClient/Employees.swift
index e295eb1..dc83d7f 100644
--- a/Sources/DatabaseClient/Employees.swift
+++ b/Sources/DatabaseClient/Employees.swift
@@ -32,3 +32,70 @@ extension Employee.Update: Content {}
 extension DatabaseClient.Employees: TestDependencyKey {
   public static let testValue = Self()
 }
+
+#if DEBUG
+
+  typealias EmployeeMockStorage = MockStorage<
+    Employee,
+    Employee.Create,
+    DatabaseClient.Employees.FetchRequest,
+    Void,
+    Employee.Update
+  >
+
+  private extension EmployeeMockStorage {
+
+    init(_ mocks: [Employee]) {
+      @Dependency(\.date.now) var now
+      @Dependency(\.uuid) var uuid
+      self.init(
+        mocks,
+        create: { employee in
+          Employee(
+            id: uuid(),
+            active: employee.active ?? true,
+            createdAt: now,
+            firstName: employee.firstName,
+            lastName: employee.lastName,
+            updatedAt: now
+          )
+        },
+        fetch: { request in
+          switch request {
+          case .all:
+            return { _ in true }
+          case .active:
+            return { $0.active == true }
+          case .inactive:
+            return { $0.active == false }
+          }
+        },
+        update: { employee, updates in
+          let model = Employee(
+            id: employee.id,
+            active: updates.active ?? employee.active,
+            createdAt: employee.createdAt,
+            firstName: updates.firstName ?? employee.firstName,
+            lastName: updates.lastName ?? employee.lastName,
+            updatedAt: now
+          )
+
+          employee = model
+        }
+      )
+    }
+  }
+
+  public extension DatabaseClient.Employees {
+    static func mock(_ mocks: [Employee] = []) -> Self {
+      let storage = EmployeeMockStorage(mocks)
+      return .init(
+        create: { try await storage.create($0) },
+        delete: { try await storage.delete($0) },
+        fetchAll: { try await storage.fetchAll($0) },
+        get: { try await storage.get($0) },
+        update: { try await storage.update($0, $1) }
+      )
+    }
+  }
+#endif
diff --git a/Sources/DatabaseClient/MockStorage.swift b/Sources/DatabaseClient/MockStorage.swift
new file mode 100644
index 0000000..32d1622
--- /dev/null
+++ b/Sources/DatabaseClient/MockStorage.swift
@@ -0,0 +1,143 @@
+#if DEBUG
+  import Dependencies
+  import Vapor
+
+  actor MockStorage<
+    Model: Identifiable,
+    Create: Sendable,
+    Fetch: Sendable,
+    Get: Sendable,
+    Update: Sendable
+  > where Model: Sendable {
+    @Dependency(\.date.now) var now
+    @Dependency(\.uuid) var uuid
+
+    private var storage: [Model.ID: Model]
+
+    private let modelFromCreate: @Sendable (Create) -> Model
+    private let fetchToPredicate: @Sendable (Fetch) -> ((Model) -> Bool)
+    private let fetchExtras: @Sendable (Fetch, [Model]) async throws -> [Model]
+    private let applyUpdates: @Sendable (inout Model, Update, Get?) async throws -> Void
+    private let getExtras: @Sendable (Get?, Model) async throws -> Model
+
+    init(
+      _ mocks: [Model] = [],
+      create modelFromCreate: @Sendable @escaping (Create) -> Model,
+      fetch fetchToPredicate: @Sendable @escaping (Fetch) -> ((Model) -> Bool),
+      fetchExtras: @Sendable @escaping (Fetch, [Model]) async throws -> [Model] = { $1 },
+      get getExtras: @Sendable @escaping (Get?, Model) async throws -> Model,
+      update applyUpdates: @Sendable @escaping (inout Model, Update, Get?) async throws -> Void
+    ) {
+      self.storage = mocks.reduce(into: [Model.ID: Model]()) { $0[$1.id] = $1 }
+      self.modelFromCreate = modelFromCreate
+      self.fetchToPredicate = fetchToPredicate
+      self.fetchExtras = fetchExtras
+      self.applyUpdates = applyUpdates
+      self.getExtras = getExtras
+    }
+
+    func count() async throws -> Int {
+      storage.count
+    }
+
+    func create(_ create: Create) async throws -> Model {
+      let model = modelFromCreate(create)
+      storage[model.id] = model
+      return model
+    }
+
+    func delete(_ id: Model.ID) async throws {
+      storage[id] = nil
+    }
+
+    func fetchAll(_ request: Fetch) async throws -> [Model] {
+      let predicate = fetchToPredicate(request)
+      return try await fetchExtras(request, Array(storage.values.filter { predicate($0) }))
+    }
+
+    func get(_ id: Model.ID, _ request: Get?) async throws -> Model? {
+      if let model = storage[id] {
+        return try await getExtras(request, model)
+      }
+      return nil
+    }
+
+    func update(_ id: Model.ID, _ updates: Update, _ get: Get?) async throws -> Model {
+      guard var model = storage[id] else {
+        throw Abort(.badRequest, reason: "Model not found.")
+      }
+      try await applyUpdates(&model, updates, get)
+      storage[id] = model
+      return model
+    }
+  }
+
+  extension MockStorage where Get == Void {
+    init(
+      _ mocks: [Model] = [],
+      create modelFromCreate: @Sendable @escaping (Create) -> Model,
+      fetch fetchToPredicate: @Sendable @escaping (Fetch) -> ((Model) -> Bool),
+      fetchExtras: @Sendable @escaping (Fetch, [Model]) async throws -> [Model] = { $1 },
+      update applyUpdates: @Sendable @escaping (inout Model, Update) async throws -> Void
+    ) {
+      self.init(
+        mocks,
+        create: modelFromCreate,
+        fetch: fetchToPredicate,
+        fetchExtras: fetchExtras,
+        get: { _, model in model },
+        update: { model, updates, _ in try await applyUpdates(&model, updates) }
+      )
+    }
+
+    func get(_ id: Model.ID) async throws -> Model? {
+      storage[id]
+    }
+
+    func update(_ id: Model.ID, _ updates: Update) async throws -> Model {
+      try await update(id, updates, ())
+    }
+
+  }
+
+  extension MockStorage where Fetch == Void {
+    init(
+      _ mocks: [Model] = [],
+      create modelFromCreate: @Sendable @escaping (Create) -> Model,
+      fetchExtras: @Sendable @escaping (Fetch, [Model]) async throws -> [Model] = { $1 },
+      get getExtras: @Sendable @escaping (Get?, Model) async throws -> Model,
+      update applyUpdates: @Sendable @escaping (inout Model, Update, Get?) async throws -> Void
+    ) {
+      self.init(
+        mocks,
+        create: modelFromCreate,
+        fetch: { _ in { _ in true } },
+        fetchExtras: fetchExtras,
+        get: getExtras,
+        update: applyUpdates
+      )
+    }
+
+    func fetchAll() async throws -> [Model] {
+      try await fetchAll(())
+    }
+  }
+
+  extension MockStorage where Fetch == Void, Get == Void {
+    init(
+      _ mocks: [Model] = [],
+      create modelFromCreate: @Sendable @escaping (Create) -> Model,
+      fetchExtras: @Sendable @escaping (Fetch, [Model]) async throws -> [Model] = { $1 },
+      update applyUpdates: @Sendable @escaping (inout Model, Update) async throws -> Void
+    ) {
+      self.init(
+        mocks,
+        create: modelFromCreate,
+        fetchExtras: fetchExtras,
+        get: { _, model in model },
+        update: { model, updates, _ in try await applyUpdates(&model, updates) }
+      )
+    }
+
+  }
+#endif
diff --git a/Sources/DatabaseClient/VendorBranches.swift b/Sources/DatabaseClient/VendorBranches.swift
index f39be7a..e82362b 100644
--- a/Sources/DatabaseClient/VendorBranches.swift
+++ b/Sources/DatabaseClient/VendorBranches.swift
@@ -15,7 +15,6 @@ public extension DatabaseClient {
     public enum FetchRequest: Equatable {
       case all
       case `for`(vendorID: Vendor.ID)
-      case withVendor
     }
 
     public func fetchAll() async throws -> [VendorBranch] {
@@ -32,3 +31,61 @@ extension DatabaseClient.VendorBranches.FetchRequest: Content {}
 extension DatabaseClient.VendorBranches: TestDependencyKey {
   public static let testValue: DatabaseClient.VendorBranches = Self()
 }
+
+#if DEBUG
+  typealias VendorBranchMockStorage = MockStorage<
+    VendorBranch,
+    VendorBranch.Create,
+    DatabaseClient.VendorBranches.FetchRequest,
+    Void,
+    VendorBranch.Update
+  >
+
+  private extension VendorBranchMockStorage {
+
+    init(_ mocks: [VendorBranch]) {
+      @Dependency(\.date.now) var now
+      @Dependency(\.uuid) var uuid
+
+      self.init(
+        mocks,
+        create: {
+          VendorBranch(id: uuid(), name: $0.name, vendorID: $0.vendorID, createdAt: now, updatedAt: now)
+        },
+        fetch: { request in
+          switch request {
+          case .all:
+            return { _ in true }
+          case let .for(vendorID):
+            return { $0.vendorID == vendorID }
+          }
+        },
+        update: { branch, updates in
+          let model = VendorBranch(
+            id: branch.id,
+            name: updates.name ?? branch.name,
+            vendorID: branch.vendorID,
+            createdAt: branch.createdAt,
+            updatedAt: now
+          )
+
+          branch = model
+        }
+      )
+    }
+  }
+
+  public extension DatabaseClient.VendorBranches {
+    static func mock(_ mocks: [VendorBranch] = []) -> Self {
+      let storage = VendorBranchMockStorage(mocks)
+      return .init(
+        create: { try await storage.create($0) },
+        delete: { try await storage.delete($0) },
+        fetchAll: { try await storage.fetchAll($0) },
+        get: { try await storage.get($0) },
+        update: { try await storage.update($0, $1) }
+      )
+    }
+  }
+
+#endif
diff --git a/Sources/DatabaseClient/Vendors.swift b/Sources/DatabaseClient/Vendors.swift
index a40804c..12c2751 100644
--- a/Sources/DatabaseClient/Vendors.swift
+++ b/Sources/DatabaseClient/Vendors.swift
@@ -51,3 +51,94 @@ extension DatabaseClient.Vendors.GetRequest: Content {}
 extension DatabaseClient.Vendors: TestDependencyKey {
   public static let testValue: DatabaseClient.Vendors = Self()
 }
+
+#if DEBUG
+
+  typealias VendorMockStorage = MockStorage<
+    Vendor,
+    Vendor.Create,
+    DatabaseClient.Vendors.FetchRequest,
+    DatabaseClient.Vendors.GetRequest,
+    Vendor.Update
+  >
+
+  private extension VendorMockStorage {
+
+    // swiftlint:disable function_body_length
+    static func vendors(_ mocks: [Vendor]) -> Self {
+      @Dependency(\.date.now) var now
+      @Dependency(\.uuid) var uuid
+      @Dependency(\.database.vendorBranches) var vendorBranches
+
+      return .init(
+        mocks,
+        create: {
+          Vendor(
+            id: uuid(),
+            name: $0.name,
+            createdAt: now,
+            updatedAt: now
+          )
+        },
+        fetch: { _ in
+          { _ in true }
+        },
+        fetchExtras: { request, models in
+          guard request == .withBranches else { return models }
+          let branches = try await vendorBranches.fetchAll()
+          return models.map { model in
+            Vendor(
+              id: model.id,
+              name: model.name,
+              branches: Array(branches.filter { $0.vendorID == model.id }),
+              createdAt: model.createdAt,
+              updatedAt: model.updatedAt
+            )
+          }
+        },
+        get: { req, model in
+          guard req == .withBranches else { return model }
+          let branches = try await vendorBranches.fetchAll(.for(vendorID: model.id))
+          return Vendor(
+            id: model.id,
+            name: model.name,
+            branches: branches,
+            createdAt: model.createdAt,
+            updatedAt: model.updatedAt
+          )
+        },
+        update: { model, updates, get in
+          var branches: [VendorBranch]?
+
+          if get == .withBranches {
+            branches = try await vendorBranches.fetchAll(.for(vendorID: model.id))
+          }
+
+          let vendor = Vendor(
+            id: model.id,
+            name: updates.name ?? model.name,
+            branches: branches ?? model.branches,
+            createdAt: model.createdAt,
+            updatedAt: now
+          )
+          model = vendor
+        }
+      )
+    }
+    // swiftlint:enable function_body_length
+  }
+
+  public extension DatabaseClient.Vendors {
+    static func mock(_ mocks: [Vendor]) -> Self {
+      let storage = VendorMockStorage.vendors(mocks)
+      return .init(
+        create: { try await storage.create($0) },
+        delete: { try await storage.delete($0) },
+        fetchAll: { try await storage.fetchAll($0) },
+        get: { try await storage.get($0, $1) },
+        update: { req, updates, get in try await storage.update(req, updates, get) }
+      )
+    }
+  }
+
+#endif
diff --git a/Sources/DatabaseClientLive/VendorBranches.swift b/Sources/DatabaseClientLive/VendorBranches.swift
index 60dab83..770797b 100644
--- a/Sources/DatabaseClientLive/VendorBranches.swift
+++ b/Sources/DatabaseClientLive/VendorBranches.swift
@@ -16,13 +16,11 @@ public extension DatabaseClient.VendorBranches {
       }
       try await model.delete(on: db)
     } fetchAll: { request in
-      var query = VendorBranchModel.query(on: db)
+      let query = VendorBranchModel.query(on: db)
 
       switch request {
       case .all:
         break
-      case .withVendor:
-        query = query.with(\.$vendor)
       case let .for(vendorID: vendorID):
         let branches = try await VendorModel.query(on: db)
           .filter(\.$id == vendorID)
diff --git a/Tests/DatabaseClientTests/DatabaseClientTests.swift b/Tests/DatabaseClientTests/DatabaseClientTests.swift
index 15e65f0..dd52856 100644
--- a/Tests/DatabaseClientTests/DatabaseClientTests.swift
+++ b/Tests/DatabaseClientTests/DatabaseClientTests.swift
@@ -1,6 +1,7 @@
 @testable import DatabaseClientLive
 import Dependencies
 import FluentSQLiteDriver
+import Foundation
 import Logging
 import NIO
 import SharedModels
@@ -48,10 +49,12 @@ struct DatabaseClientTests {
     }
   }
 
-  @Test
-  func employees() async throws {
+  @Test(arguments: EmployeeTestFactory.testCases)
+  func employees(factory: EmployeeTestFactory) async throws {
     try await withDatabase(migrations: Employee.Migrate()) {
-      $0.database.employees = .live(database: $1)
+      $0.uuid = .incrementing
+      $0.date = .init { Date() }
+      $0.database.employees = factory.handler($1)
     } operation: {
       @Dependency(\.database.employees) var employees
 
@@ -90,11 +93,11 @@ struct DatabaseClientTests {
     }
   }
 
-  @Test
-  func vendors() async throws {
+  @Test(arguments: VendorTestFactory.testCases)
+  func vendors(factory: VendorTestFactory) async throws {
     try await withDatabase(migrations: Vendor.Migrate(), VendorBranch.Migrate()) {
-      $0.database.vendors = .live(database: $1)
-      $0.database.vendorBranches = .live(database: $1)
+      $0.database.vendorBranches = factory.handler($1).0
+      $0.database.vendors = factory.handler($1).1
     } operation: {
       @Dependency(\.database.vendorBranches) var branches
       @Dependency(\.database.vendors) var vendors
@@ -119,7 +122,7 @@ struct DatabaseClientTests {
       let fetchedWithBranches = try await vendors.get(vendor.id, .withBranches)
       #expect(fetchedWithBranches!.branches!.first == branch)
 
-      let updated = try await vendors.update(vendor.id, .init(name: "Johnstone"))
+      let updated = try await vendors.update(vendor.id, with: .init(name: "Johnstone"))
       #expect(updated.name == "Johnstone")
 
       try await vendors.delete(vendor.id)
@@ -129,11 +132,11 @@ struct DatabaseClientTests {
     }
   }
 
-  @Test
-  func vendorBranches() async throws {
+  @Test(arguments: VendorTestFactory.testCases)
+  func vendorBranches(factory: VendorTestFactory) async throws {
     try await withDatabase(migrations: Vendor.Migrate(), VendorBranch.Migrate()) {
-      $0.database.vendors = .live(database: $1)
-      $0.database.vendorBranches = .live(database: $1)
+      $0.database.vendorBranches = factory.handler($1).0
+      $0.database.vendors = factory.handler($1).1
     } operation: {
       @Dependency(\.database.vendorBranches) var branches
       @Dependency(\.database.vendors) var vendors
@@ -180,6 +183,8 @@ struct DatabaseClientTests {
     }
 
     try await withDependencies {
+      $0.uuid = .incrementing
+      $0.date = .init { Date() }
       setupDependencies(&$0, database)
     } operation: {
       try await operation()
@@ -192,3 +197,22 @@ struct DatabaseClientTests {
     await dbs.shutdownAsync()
   }
 }
+
+struct EmployeeTestFactory {
+  let handler: (any Database) -> DatabaseClient.Employees
+
+  static var testCases: [Self] { [
+    .init(handler: { .live(database: $0) }),
+    .init(handler: { _ in .mock([]) })
+  ] }
+}
+
+struct VendorTestFactory {
+  let handler: (any Database) -> (DatabaseClient.VendorBranches, DatabaseClient.Vendors)
+
+  static var testCases: [Self] { [
+    .init(handler: { (.live(database: $0), .live(database: $0)) }),
+    .init(handler: { _ in (.mock([]), .mock([])) })
+  ] }
+
+}