diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index aa07dcc..6b6b653 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -9,7 +9,7 @@ variables:
 test:backend:
     image: docker:latest
     services:
-        - mariadb:10.0
+        - mariadb:10.2.11
         - redis:3.0-alpine
     variables:
         # mariadb config
diff --git a/console/db/Migration.php b/console/db/Migration.php
index dd1cc3c..9633643 100644
--- a/console/db/Migration.php
+++ b/console/db/Migration.php
@@ -11,7 +11,7 @@ class Migration extends YiiMigration {
     public function getTableOptions($engine = 'InnoDB') {
         $tableOptions = null;
         if ($this->db->driverName === 'mysql') {
-            $tableOptions = 'CHARACTER SET utf8 COLLATE utf8_general_ci ENGINE=' . $engine;
+            $tableOptions = 'CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci ENGINE=' . $engine;
         }
 
         return $tableOptions;
diff --git a/console/migrations/m171222_200114_migrate_to_utf8md4_unicode_ci.php b/console/migrations/m171222_200114_migrate_to_utf8md4_unicode_ci.php
new file mode 100644
index 0000000..0fef2b7
--- /dev/null
+++ b/console/migrations/m171222_200114_migrate_to_utf8md4_unicode_ci.php
@@ -0,0 +1,37 @@
+<?php
+
+use console\db\Migration;
+
+class m171222_200114_migrate_to_utf8md4_unicode_ci extends Migration {
+
+    public function safeUp() {
+        $this->execute('SET FOREIGN_KEY_CHECKS=0');
+
+        $dbName = $this->db->createCommand('SELECT DATABASE()')->queryScalar();
+        $this->execute("ALTER DATABASE {{%$dbName}} CHARACTER SET = utf8mb4 COLLATE = utf8mb4_unicode_ci");
+        $tables = $this->db->createCommand('SHOW TABLES')->queryColumn();
+        foreach ($tables as $table) {
+            $this->execute("ALTER TABLE {{%$table}} CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci");
+        }
+
+        $this->execute('ALTER TABLE {{%usernames_history}} MODIFY username VARCHAR(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_bin NOT NULL');
+
+        $this->execute('SET FOREIGN_KEY_CHECKS=1');
+    }
+
+    public function safeDown() {
+        $this->execute('SET FOREIGN_KEY_CHECKS=0');
+
+        $dbName = $this->db->createCommand('SELECT DATABASE()')->queryScalar();
+        $this->execute("ALTER DATABASE {{%$dbName}} CHARACTER SET = utf8 COLLATE = utf8_general_ci");
+        $tables = $this->db->createCommand('SHOW TABLES')->queryColumn();
+        foreach ($tables as $table) {
+            $this->execute("ALTER TABLE {{%$table}} CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci");
+        }
+
+        $this->execute('ALTER TABLE {{%usernames_history}} MODIFY username VARCHAR(255) CHARACTER SET utf8 COLLATE utf8_bin NOT NULL');
+
+        $this->execute('SET FOREIGN_KEY_CHECKS=1');
+    }
+
+}
diff --git a/docker/mariadb/Dockerfile b/docker/mariadb/Dockerfile
index 68358b6..2dabddb 100644
--- a/docker/mariadb/Dockerfile
+++ b/docker/mariadb/Dockerfile
@@ -1,4 +1,4 @@
-FROM mariadb:10.0
+FROM mariadb:10.2.11
 
 COPY custom.cnf /etc/mysql/conf.d/
 
diff --git a/docker/mariadb/custom.cnf b/docker/mariadb/custom.cnf
index 0cf5418..66a1832 100644
--- a/docker/mariadb/custom.cnf
+++ b/docker/mariadb/custom.cnf
@@ -1,9 +1,9 @@
 [mysql]
-default-character-set = utf8
+default-character-set = utf8mb4
 
 [mysqld]
-character-set-server = utf8
-collation-server = utf8_general_ci
+character-set-server = utf8mb4
+collation-server = utf8mb4_unicode_ci
 
 [client]
-default-character-set = utf8
+default-character-set = utf8mb4