diff --git a/BeReal/ContentView.swift b/BeReal/ContentView.swift
index 12650bb..2c544e1 100644
--- a/BeReal/ContentView.swift
+++ b/BeReal/ContentView.swift
@@ -6,22 +6,42 @@
 //  Copyright © 2022 Röck+Cöde. All rights reserved.
 //
 
-import SwiftUI
 import Browse
+import DataModels
 import Login
+import KeychainStorage
 import Profile
+import SwiftUI
 
 struct ContentView: View {
+    
+    // MARK: Storages
+    
+    @KeychainStorage(key: .KeychainStorage.account) private var account: Account?
+    
+    // MARK: Body
+    
     var body: some View {
         NavigationView {
             BrowseView()
         }
-        .sheet(isPresented: .constant(true)) {
-            ProfileView {}
+        .sheet(isPresented: showLogin) {
+            LoginView()
         }
     }
+
 }
 
+// MARK: - Helpers
+
+private extension ContentView {
+    var showLogin: Binding<Bool> {
+        .init { account == nil } set: { _ in }
+    }
+}
+
+// MARK: - Previews
+
 struct ContentView_Previews: PreviewProvider {
     static var previews: some View {
         ContentView()
diff --git a/Libraries/Package.swift b/Libraries/Package.swift
index 14d92b0..f4e096b 100644
--- a/Libraries/Package.swift
+++ b/Libraries/Package.swift
@@ -10,6 +10,8 @@ let package = Package(
             name: "Libraries",
             targets: [
                 "APIService",
+                "DataModels",
+                "Dependencies",
                 "KeychainStorage"
             ]
         ),
@@ -23,6 +25,7 @@ let package = Package(
     ],
     targets: [
         .target(name: "APIService"),
+        .target(name: "DataModels"),
         .target(
             name: "Dependencies",
             dependencies: [
diff --git a/Libraries/Sources/APIService/Models/Item.swift b/Libraries/Sources/APIService/Models/Item.swift
index e607a77..fc82509 100644
--- a/Libraries/Sources/APIService/Models/Item.swift
+++ b/Libraries/Sources/APIService/Models/Item.swift
@@ -9,13 +9,13 @@
 import Foundation
 
 public struct Item {
-    let idParent: String?
-    let id: String
-    let name: String
-    let isDirectory: Bool
-    let lastModifiedAt: Date
-    let size: Int?
-    let contentType: String?
+    public let idParent: String?
+    public let id: String
+    public let name: String
+    public let isDirectory: Bool
+    public let lastModifiedAt: Date
+    public let size: Int?
+    public let contentType: String?
 }
 
 // MARK: - Decodable
diff --git a/Libraries/Sources/APIService/Models/Me.swift b/Libraries/Sources/APIService/Models/Me.swift
index 35c1b87..3a3e287 100644
--- a/Libraries/Sources/APIService/Models/Me.swift
+++ b/Libraries/Sources/APIService/Models/Me.swift
@@ -7,9 +7,9 @@
 //
 
 public struct Me {
-    let firstName: String
-    let lastName: String
-    let rootItem: Item
+    public let firstName: String
+    public let lastName: String
+    public let rootItem: Item
 }
 
 // MARK: - Decodable
diff --git a/Libraries/Sources/DataModels/Keys/String+KeychainStorageKeys.swift b/Libraries/Sources/DataModels/Keys/String+KeychainStorageKeys.swift
new file mode 100644
index 0000000..e744ff8
--- /dev/null
+++ b/Libraries/Sources/DataModels/Keys/String+KeychainStorageKeys.swift
@@ -0,0 +1,13 @@
+//
+//  String+KeychainStorageKeys.swift
+//  DataModels
+//
+//  Created by Javier Cicchelli on 11/12/2022.
+//  Copyright © 2022 Röck+Cöde. All rights reserved.
+//
+
+public extension String {
+    enum KeychainStorage {
+        public static let account = "com.rockncode.app.assignment.be-real.library.data-models.keychain.key.account"
+    }
+}
diff --git a/Libraries/Sources/DataModels/Models/Account.swift b/Libraries/Sources/DataModels/Models/Account.swift
new file mode 100644
index 0000000..c0b1711
--- /dev/null
+++ b/Libraries/Sources/DataModels/Models/Account.swift
@@ -0,0 +1,26 @@
+//
+//  Account.swift
+//  DataModels
+//
+//  Created by Javier Cicchelli on 11/12/2022.
+//  Copyright © 2022 Röck+Cöde. All rights reserved.
+//
+
+public struct Account: Codable {
+    
+    // MARK: Properties
+    
+    public let username: String
+    public let password: String
+    
+    // MARK: Initialisers
+    
+    public init(
+        username: String,
+        password: String
+    ) {
+        self.username = username
+        self.password = password
+    }
+
+}
diff --git a/Libraries/Sources/DataModels/Models/User.swift b/Libraries/Sources/DataModels/Models/User.swift
new file mode 100644
index 0000000..6a5e1cc
--- /dev/null
+++ b/Libraries/Sources/DataModels/Models/User.swift
@@ -0,0 +1,73 @@
+//
+//  User.swift
+//  DataModels
+//
+//  Created by Javier Cicchelli on 11/12/2022.
+//  Copyright © 2022 Röck+Cöde. All rights reserved.
+//
+
+import Foundation
+
+public struct User {
+    
+    // MARK: Properties
+    
+    public let profile: Profile
+    public let rootFolder: RootFolder
+    
+    // MARK: Initialisers
+    
+    public init(
+        profile: Profile,
+        rootFolder: RootFolder
+    ) {
+        self.profile = profile
+        self.rootFolder = rootFolder
+    }
+
+}
+
+// MARK: - Structs
+
+extension User {
+    public struct Profile {
+        
+        // MARK: Properties
+        
+        public let firstName: String
+        public let lastName: String
+        
+        // MARK: Initialisers
+        
+        public init(
+            firstName: String,
+            lastName: String
+        ) {
+            self.firstName = firstName
+            self.lastName = lastName
+        }
+
+    }
+    
+    public struct RootFolder {
+        
+        // MARK: Properties
+        
+        public let id: String
+        public let name: String
+        public let lastModifiedAt: Date
+        
+        // MARK: Initialisers
+        
+        public init(
+            id: String,
+            name: String,
+            lastModifiedAt: Date
+        ) {
+            self.id = id
+            self.name = name
+            self.lastModifiedAt = lastModifiedAt
+        }
+
+    }
+}
diff --git a/Libraries/Sources/Dependencies/Keys/APIServiceKey.swift b/Libraries/Sources/Dependencies/Keys/APIServiceKey.swift
index e118aaf..88eed55 100644
--- a/Libraries/Sources/Dependencies/Keys/APIServiceKey.swift
+++ b/Libraries/Sources/Dependencies/Keys/APIServiceKey.swift
@@ -9,6 +9,6 @@
 import APIService
 import DependencyInjection
 
-struct APIServiceKey: DependencyKey {
-    static var currentValue = APIService()
+public struct APIServiceKey: DependencyKey {
+    public static var currentValue = APIService()
 }
diff --git a/Libraries/Sources/KeychainStorage/Property Wrappers/KeychainStorage.swift b/Libraries/Sources/KeychainStorage/Property Wrappers/KeychainStorage.swift
index 11fc43f..34f8332 100644
--- a/Libraries/Sources/KeychainStorage/Property Wrappers/KeychainStorage.swift	
+++ b/Libraries/Sources/KeychainStorage/Property Wrappers/KeychainStorage.swift	
@@ -62,13 +62,11 @@ public struct KeychainStorage<Model: Codable>: DynamicProperty {
         self.keychain = keychain
         
         do {
-            let data = try keychain.getData(key, ignoringAttributeSynchronizable: true)
-            
-            guard let data else {
-                assertionFailure("The data of the '\(key)' key should have been obtained from the keychain storage.")
+            guard let data = try keychain.getData(key, ignoringAttributeSynchronizable: true) else {
+                self._value = .init(initialValue: defaultValue)
                 return
             }
-            
+
             do {
                 let model = try decoder.decode(Value.self, from: data)
                 
@@ -77,7 +75,7 @@ public struct KeychainStorage<Model: Codable>: DynamicProperty {
                 assertionFailure("The data for the '\(key)' key should have been decoded properly.")
             }
         } catch {
-            self._value = .init(initialValue: defaultValue)
+            assertionFailure("The data of the '\(key)' key should have been obtained from the keychain storage.")
         }
     }
     
diff --git a/Modules/Package.swift b/Modules/Package.swift
index 6e6f8a9..5e4826e 100644
--- a/Modules/Package.swift
+++ b/Modules/Package.swift
@@ -5,9 +5,7 @@ import PackageDescription
 let package = Package(
     name: "Modules",
     defaultLocalization: "en",
-    platforms: [
-        .iOS(.v15)
-    ],
+    platforms: [.iOS(.v15)],
     products: [
         .library(
             name: "Modules",
@@ -18,9 +16,17 @@ let package = Package(
             ]
         ),
     ],
+    dependencies: [
+        .package(path: "../Cores"),
+        .package(path: "../Libraries")
+    ],
     targets: [
         .target(
             name: "Login",
+            dependencies: [
+                "Cores",
+                "Libraries"
+            ],
             resources: [.process("Resources")]
         ),
         .target(
diff --git a/Modules/Sources/Login/Resources/en.lproj/Localizable.strings b/Modules/Sources/Login/Resources/en.lproj/Localizable.strings
index bd901a9..f571afc 100644
--- a/Modules/Sources/Login/Resources/en.lproj/Localizable.strings
+++ b/Modules/Sources/Login/Resources/en.lproj/Localizable.strings
@@ -10,3 +10,6 @@
 "login.text_field.username.placeholder" = "Username";
 "login.text_field.password.placeholder" = "Password";
 "login.button.log_in.text" = "Log in";
+
+"login.error.authentication_failed.text" = "The given username and/or password are not correct.\nPlease re-enter your credentials and try again.";
+"login.error.authentication_unknown.text" = "An unexpected error occurred while trying to authenticate your credentials.\nPlease try again at a later time.";
diff --git a/Modules/Sources/Login/UI/Components/LoginForm.swift b/Modules/Sources/Login/UI/Components/LoginForm.swift
index c40fc6c..5bb0711 100644
--- a/Modules/Sources/Login/UI/Components/LoginForm.swift
+++ b/Modules/Sources/Login/UI/Components/LoginForm.swift
@@ -38,11 +38,7 @@ struct LoginForm: View {
                     comment: "The placeholder for the username text field."
                 ),
                 text: $username
-            ) { isBeginEditing in
-                guard isBeginEditing, errorMessage != nil else { return }
-                
-                errorMessage = nil
-            }
+            )
             .textContentType(.username)
             .lineLimit(1)
             .autocapitalization(.none)
@@ -76,9 +72,17 @@ struct LoginForm: View {
             if let errorMessage {
                 Divider()
                 
-                Text(errorMessage)
-                    .font(.body)
-                    .foregroundColor(.red)
+                Text(
+                    NSLocalizedString(
+                        errorMessage,
+                        bundle: .module,
+                        comment: "The error message received from the backend."
+                    )
+                )
+                .font(.body)
+                .foregroundColor(.red)
+                .frame(maxWidth: .infinity)
+                .multilineTextAlignment(.center)
             }
         }
         .frame(maxWidth: .infinity, alignment: .leading)
@@ -88,6 +92,9 @@ struct LoginForm: View {
         .onAppear {
             setClearButtonIfNeeded()
         }
+        .onChange(of: focusedField) { _ in
+            onTextFieldFocused()
+        }
     }
 }
 
@@ -101,6 +108,13 @@ private extension LoginForm {
         textFieldAppearance.clearButtonMode = .whileEditing
     }
     
+    func onTextFieldFocused() {
+        guard errorMessage != nil else { return }
+        
+        password = ""
+        errorMessage = nil
+    }
+    
     func onUsernameReturnPressed() {
         guard !username.isEmpty else { return }
         
diff --git a/Modules/Sources/Login/UI/Views/LoginView.swift b/Modules/Sources/Login/UI/Views/LoginView.swift
index 392073b..754fe4c 100644
--- a/Modules/Sources/Login/UI/Views/LoginView.swift
+++ b/Modules/Sources/Login/UI/Views/LoginView.swift
@@ -6,6 +6,11 @@
 //  Copyright © 2022 Röck+Cöde. All rights reserved.
 //
 
+import APIService
+import DataModels
+import DependencyInjection
+import Dependencies
+import KeychainStorage
 import SwiftUI
 
 public struct LoginView: View {
@@ -43,6 +48,14 @@ public struct LoginView: View {
 fileprivate extension LoginView {
     struct LoginContainer: View {
         
+        // MARK: Dependencies
+        
+        @Dependency(\.apiService) private var apiService
+        
+        // MARK: Storages
+        
+        @KeychainStorage(key: .KeychainStorage.account) private var account: Account?
+        
         // MARK: States
         
         @State private var isAuthenticating: Bool = false
@@ -68,11 +81,11 @@ fileprivate extension LoginView {
                     password: $password,
                     errorMessage: $errorMessage
                 ) {
-                    // TODO: login with the username and password.
+                    isAuthenticating = true
                 }
 
                 Button {
-                    // TODO: login with the username and password.
+                    isAuthenticating = true
                 } label: {
                     Label {
                         Text(
@@ -84,6 +97,7 @@ fileprivate extension LoginView {
                     } icon: {
                         if isAuthenticating {
                             ProgressView()
+                                .controlSize(.regular)
                         } else {
                             EmptyView()
                         }
@@ -95,6 +109,9 @@ fileprivate extension LoginView {
                 .buttonBorderShape(.roundedRectangle(radius: 8))
                 .controlSize(.large)
                 .disabled(isLoginDisabled)
+                .task(id: isAuthenticating) {
+                    await authenticate()
+                }
             }
         }
     }
@@ -103,9 +120,37 @@ fileprivate extension LoginView {
 // MARK: - Helpers
 
 private extension LoginView.LoginContainer {
+    
+    // MARK: Computed
+    
     var isLoginDisabled: Bool {
         username.isEmpty || password.isEmpty
     }
+    
+    // MARK: Functions
+    
+    func authenticate() async {
+        guard isAuthenticating else { return }
+        
+        do {
+            _ = try await apiService.getUser(credentials: .init(
+                username: username,
+                password: password
+            ))
+            
+            account = .init(
+                username: username,
+                password: password
+            )
+        } catch APIClientError.authenticationFailed {
+            errorMessage = "login.error.authentication_failed.text"
+            isAuthenticating = false
+        } catch {
+            errorMessage = "login.error.authentication_unknown.text"
+            isAuthenticating = false
+        }
+    }
+
 }
 
 // MARK: - Previews