diff --git a/src/Controller/LoginController.php b/src/Controller/LoginController.php
index 566f218..a858949 100644
--- a/src/Controller/LoginController.php
+++ b/src/Controller/LoginController.php
@@ -2,6 +2,7 @@
 
 use DateInterval;
 use DateTime;
+use Faker\Factory;
 use SokoWeb\Http\Request;
 use SokoWeb\Interfaces\Response\IContent;
 use SokoWeb\Interfaces\Response\IRedirect;
@@ -89,8 +90,13 @@ class LoginController
         return new HtmlContent('login/signup', $data);
     }
 
-    public function getSignupSuccess(): IContent
+    public function getSignupSuccess()
     {
+        if (\Container::$request->user() !== null) {
+            $this->deleteRedirectUrl();
+            return new Redirect($this->redirectUrl, IRedirect::TEMPORARY);
+        }
+
         return new HtmlContent('login/signup_success');
     }
 
@@ -265,131 +271,128 @@ class LoginController
             return new JsonContent(['redirect' => ['target' => $this->redirectUrl]]);
         }
 
-        $user = $this->userRepository->getByEmail(\Container::$request->post('email'));
+        $newUser = new User();
 
-        if ($user !== null) {
-            if ($user->getActive()) {
-                if (!$user->checkPassword(\Container::$request->post('password'))) {
-                    return new JsonContent([
-                        'error' => [
-                            'errorText' => 'There is a user already registered with the given email address, ' .
-                                'but the given password is wrong. You can <a href="/password/requestReset?email=' .
-                                urlencode($user->getEmail()) . '" title="Request password reset">request password reset</a>!'
-                        ]
-                    ]);
-                }
+        $googleUserData = \Container::$request->session()->get('google_user_data');
+        if ($googleUserData !== null) {
+            $user = $this->userRepository->getByEmail($googleUserData['email']);
 
-                \Container::$request->setUser($user);
-
-                $this->deleteRedirectUrl();
-                $data = ['redirect' => ['target' => $this->redirectUrl]];
-            } else {
-                $data = [
-                    'error' => [
-                        'errorText' => 'There is a user already registered with the given email address. ' .
-                            'Please check your email and click on the activation link!'
-                    ]
-                ];
-            }
-            return new JsonContent($data);
-        }
-
-        if (!empty($_ENV['RECAPTCHA_SITEKEY'])) {
-            if (!\Container::$request->post('g-recaptcha-response')) {
-                return new JsonContent(['error' => ['errorText' => 'Please check "I\'m not a robot" in the reCAPTCHA box!']]);
-            }
-
-            $captchaValidator = new CaptchaValidator();
-            $captchaResponse = $captchaValidator->validate(\Container::$request->post('g-recaptcha-response'));
-            if (!$captchaResponse['success']) {
-                return new JsonContent(['error' => ['errorText' => 'reCAPTCHA challenge failed. Please try again!']]);
-            }
-        }
-
-        if (filter_var(\Container::$request->post('email'), FILTER_VALIDATE_EMAIL) === false) {
-            return new JsonContent(['error' => ['errorText' => 'The given email address is not valid.']]);
-        }
-
-        if (\Container::$request->session()->has('tmp_user_data')) {
-            $tmpUserData = \Container::$request->session()->get('tmp_user_data');
-
-            $tmpUser = new User();
-            $tmpUser->setPassword($tmpUserData['password_hashed']);
-
-            if (!$tmpUser->checkPassword(\Container::$request->post('password'))) {
-                return new JsonContent(['error' => ['errorText' => 'The given passwords do not match.']]);
-            }
-        } else {
-            if (strlen(\Container::$request->post('password')) < 6) {
+            if ($user !== null) {
                 return new JsonContent([
                     'error' => [
-                        'errorText' => 'The given password is too short. Please choose a password that is at least 6 characters long!'
+                        'errorText' => 'There is a user already registered with the email address of this Google account, ' .
+                            'but Google account is not linked to the user. Please <a href="/login?email=' .
+                            urlencode($googleUserData['email']) . '" title="Login">login</a> first to link your Google account!'
                     ]
                 ]);
             }
 
-            if (\Container::$request->post('password') !== \Container::$request->post('password_confirm')) {
-                return new JsonContent(['error' => ['errorText' => 'The given passwords do not match.']]);
+            $newUser->setActive(true);
+            $newUser->setEmail($googleUserData['email']);
+            $newUser->setGoogleSub($googleUserData['sub']);
+        } else {
+            $user = $this->userRepository->getByEmailOrUsername(\Container::$request->post('email'));
+
+            if ($user !== null) {
+                if ($user->getActive()) {
+                    if (!$user->checkPassword(\Container::$request->post('password'))) {
+                        return new JsonContent([
+                            'error' => [
+                                'errorText' => 'There is a user already registered with the given email address / username, ' .
+                                    'but the given password is wrong. You can <a href="/password/requestReset?email=' .
+                                    urlencode($user->getEmail()) . '" title="Request password reset">request password reset</a>!'
+                            ]
+                        ]);
+                    }
+
+                    \Container::$request->setUser($user);
+
+                    $this->deleteRedirectUrl();
+                    $data = ['redirect' => ['target' => $this->redirectUrl]];
+                } else {
+                    $data = [
+                        'error' => [
+                            'errorText' => 'There is a user already registered with the given email address / username. ' .
+                                'Please check your email and click on the activation link!'
+                        ]
+                    ];
+                }
+                return new JsonContent($data);
             }
+
+            if (!empty($_ENV['RECAPTCHA_SITEKEY'])) {
+                if (!\Container::$request->post('g-recaptcha-response')) {
+                    return new JsonContent(['error' => ['errorText' => 'Please check "I\'m not a robot" in the reCAPTCHA box!']]);
+                }
+
+                $captchaValidator = new CaptchaValidator();
+                $captchaResponse = $captchaValidator->validate(\Container::$request->post('g-recaptcha-response'));
+                if (!$captchaResponse['success']) {
+                    return new JsonContent(['error' => ['errorText' => 'reCAPTCHA challenge failed. Please try again!']]);
+                }
+            }
+
+            if (filter_var(\Container::$request->post('email'), FILTER_VALIDATE_EMAIL) === false) {
+                return new JsonContent(['error' => ['errorText' => 'The given email address is not valid.']]);
+            }
+
+            if (\Container::$request->session()->has('tmp_user_data')) {
+                $tmpUserData = \Container::$request->session()->get('tmp_user_data');
+
+                $tmpUser = new User();
+                $tmpUser->setPassword($tmpUserData['password_hashed']);
+
+                if (!$tmpUser->checkPassword(\Container::$request->post('password'))) {
+                    return new JsonContent(['error' => ['errorText' => 'The given passwords do not match.']]);
+                }
+            } else {
+                if (strlen(\Container::$request->post('password')) < 6) {
+                    return new JsonContent([
+                        'error' => [
+                            'errorText' => 'The given password is too short. Please choose a password that is at least 6 characters long!'
+                        ]
+                    ]);
+                }
+
+                if (\Container::$request->post('password') !== \Container::$request->post('password_confirm')) {
+                    return new JsonContent(['error' => ['errorText' => 'The given passwords do not match.']]);
+                }
+            }
+
+            $newUser->setActive(false);
+            $newUser->setEmail(\Container::$request->post('email'));
+            $newUser->setPlainPassword(\Container::$request->post('password'));
         }
 
-        $user = new User();
-        $user->setEmail(\Container::$request->post('email'));
-        $user->setPlainPassword(\Container::$request->post('password'));
-        $user->setCreatedDate(new DateTime());
+        if (strlen(\Container::$request->post('username')) > 0 && preg_match('/^[a-zA-Z0-9_\-\.]+$/', \Container::$request->post('username')) !== 1) {
+            return new JsonContent(['error' => ['errorText' => 'Username can contain only english letters, digits, - (hyphen), . (dot), _ (underscore).']]);
+        }
 
-        \Container::$persistentDataManager->saveToDb($user);
+        $newUser->setUsername(strlen(\Container::$request->post('username')) > 0 ? \Container::$request->post('username') : Factory::create()->userName);
+        $newUser->setCreatedDate(new DateTime());
 
-        $token = bin2hex(random_bytes(16));
+        \Container::$persistentDataManager->saveToDb($newUser);
 
-        $confirmation = new UserConfirmation();
-        $confirmation->setUser($user);
-        $confirmation->setToken($token);
-        $confirmation->setLastSentDate(new DateTime());
+        if ($googleUserData !== null) {
+            $this->sendWelcomeEmail($newUser->getEmail());
 
-        \Container::$persistentDataManager->saveToDb($confirmation);
+            \Container::$request->setUser($newUser);
+        } else {
+            $token = bin2hex(random_bytes(16));
 
-        $this->sendConfirmationEmail($user->getEmail(), $token, $user->getCreatedDate());
+            $confirmation = new UserConfirmation();
+            $confirmation->setUser($newUser);
+            $confirmation->setToken($token);
+            $confirmation->setLastSentDate(new DateTime());
+
+            \Container::$persistentDataManager->saveToDb($confirmation);
+
+            $this->sendConfirmationEmail($newUser->getEmail(), $token, $newUser->getCreatedDate());
+        }
 
         \Container::$request->session()->delete('tmp_user_data');
-
-        return new JsonContent(['success' => true]);
-    }
-
-    public function signupWithGoogle(): IContent
-    {
-        if (\Container::$request->user() !== null) {
-            $this->deleteRedirectUrl();
-            return new JsonContent(['success' => true]);
-        }
-
-        $userData = \Container::$request->session()->get('google_user_data');
-
-        $user = $this->userRepository->getByEmail($userData['email']);
-
-        if ($user === null) {
-            $sendWelcomeEmail = true;
-
-            $user = new User();
-            $user->setEmail($userData['email']);
-            $user->setCreatedDate(new DateTime());
-        } else {
-            $sendWelcomeEmail = false;
-        }
-
-        $user->setActive(true);
-        $user->setGoogleSub($userData['sub']);
-
-        \Container::$persistentDataManager->saveToDb($user);
-
-        if ($sendWelcomeEmail) {
-            $this->sendWelcomeEmail($user->getEmail());
-        }
-
         \Container::$request->session()->delete('google_user_data');
-        \Container::$request->setUser($user);
 
-        $this->deleteRedirectUrl();
         return new JsonContent(['success' => true]);
     }
 
diff --git a/views/login/google_signup.php b/views/login/google_signup.php
index e056e58..77a478f 100644
--- a/views/login/google_signup.php
+++ b/views/login/google_signup.php
@@ -5,21 +5,13 @@
 @section(main)
     <h2>Sign up</h2>
     <div class="box">
-        <form id="googleSignupForm" action="/signup/google" method="post" data-redirect-on-success="<?= $redirectUrl ?>">
-            <?php if ($found): ?>
-                <p class="justify">Please confirm that you link your account to your Google account.</p>
-            <?php else: ?>
-                <p class="justify">Please confirm your sign up request. Your account will be linked to your Google account.</p>
-            <?php endif; ?>
+        <form id="googleSignupForm" action="/signup" method="post" data-redirect-on-success="/signup/success">
+            <p class="justify">Please confirm your sign up request. Your account will be linked to your Google account.</p>
             <input type="email" class="text big fullWidth marginTop" name="email" placeholder="Email address" value="<?= $email ?>" disabled>
+            <input type="username" class="text big fullWidth marginTop" name="username" placeholder="Username">
+            <p id="googleSignupFormError" class="formError justify marginTop"></p>
             <div class="right">
-                <button class="marginTop marginRight" type="submit">
-                    <?php if ($found): ?>
-                        Link
-                    <?php else: ?>
-                        Sign up
-                    <?php endif; ?>
-                </button><!--
+                <button class="marginTop marginRight" type="submit">Sign up</button><!--
              --><button id="cancelGoogleSignupButton" class="gray marginTop" type="button">Cancel</button>
             </div>
         </form>
diff --git a/views/login/signup.php b/views/login/signup.php
index e9dcde5..76a5bfb 100644
--- a/views/login/signup.php
+++ b/views/login/signup.php
@@ -8,7 +8,7 @@
     <div class="box">
         <form id="signupForm" action="/signup" method="post" data-redirect-on-success="/signup/success">
             <?php if (isset($email)): ?>
-                <p class="justify">No user found with the given email address. Sign up with one click!</p>
+                <p class="justify">No user found with the given email address / username. Sign up with one click!</p>
                 <input type="email" class="text big fullWidth marginTop" name="email" placeholder="Email address" autocomplete="username" value="<?= $email ?>" required>
                 <input type="password" class="text big fullWidth marginTop" name="password" placeholder="Password confirmation" autocomplete="new-password" required minlength="6" autofocus>
             <?php else: ?>
@@ -16,6 +16,7 @@
                 <input type="password" class="text big fullWidth marginTop" name="password" placeholder="Password" autocomplete="new-password" required minlength="6">
                 <input type="password" class="text big fullWidth marginTop" name="password_confirm" placeholder="Password confirmation" autocomplete="new-password" minlength="6">
             <?php endif; ?>
+            <input type="username" class="text big fullWidth marginTop" name="username" placeholder="Username">
             <?php if (!empty($_ENV['RECAPTCHA_SITEKEY'])): ?>
                 <div class="marginTop">
                     <div class="g-recaptcha" data-sitekey="<?= $_ENV['RECAPTCHA_SITEKEY'] ?>"></div>
diff --git a/web.php b/web.php
index 0dad311..c557cfc 100644
--- a/web.php
+++ b/web.php
@@ -38,7 +38,6 @@ Container::$routeCollection->group('signup', function (RouteCollection $routeCol
     $routeCollection->get('signup', '', [LoginController::class, 'getSignupForm']);
     $routeCollection->post('signup-action', '', [LoginController::class, 'signup']);
     $routeCollection->get('signup-google', 'google', [LoginController::class, 'getSignupWithGoogleForm']);
-    $routeCollection->post('signup-google-action', 'google', [LoginController::class, 'signupWithGoogle']);
     $routeCollection->post('signup.reset', 'reset', [LoginController::class, 'resetSignup']);
     $routeCollection->post('signup-google.reset', 'google/reset', [LoginController::class, 'resetGoogleSignup']);
     $routeCollection->get('signup.success', 'success', [LoginController::class, 'getSignupSuccess']);