diff --git a/CHANGELOG.md b/CHANGELOG.md
index c926ac0..efe363a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -23,6 +23,7 @@ Latest
 * [#119](https://github.com/cleverage/ui-process-bundle/issues/119) Launch form: a context row without key is left out of the context (reported by its `NotBlank` constraint): it gave a 500 when the process has constraints on the context, and a PHP 8.5 deprecation (`null` array offset). Add tests.
 * [#121](https://github.com/cleverage/ui-process-bundle/issues/121) `ListAction` / `LaunchAction`: accessed directly (`/process/list`, `/process/launch`), redirected to the dashboard (`/process?routeName=...`) instead of a 500. Add tests.
 * [#123](https://github.com/cleverage/ui-process-bundle/issues/123) HTTP API: the parameters of the query string are also read without body, and `queue` is read from the query string (the form data takes precedence). Add tests.
+* [#125](https://github.com/cleverage/ui-process-bundle/issues/125) `ProcessSchedule::getContext()` decodes a JSON string as an array; `User::getRoles()` no longer duplicates `ROLE_USER`; `symfony/expression-language` declared (used by `Assert\When`); the `underscore_number_aware` Doctrine naming strategy prerequisite is documented. Add tests.
 
 v3.0.2
 ------
diff --git a/composer.json b/composer.json
index c538091..b51399c 100644
--- a/composer.json
+++ b/composer.json
@@ -53,6 +53,7 @@
     "symfony/doctrine-messenger": "^6.4 || ^7.4 || ^8",
     "symfony/dotenv": "^6.4 || ^7.4 || ^8",
     "symfony/event-dispatcher": "^6.4 || ^7.4 || ^8",
+    "symfony/expression-language": "^6.4 || ^7.4 || ^8",
     "symfony/filesystem": "^6.4 || ^7.4 || ^8",
     "symfony/finder": "^6.4 || ^7.4 || ^8",
     "symfony/form": "^6.4 || ^7.4 || ^8",
diff --git a/docs/index.md b/docs/index.md
index 5fd9e7c..7c10dc7 100644
--- a/docs/index.md
+++ b/docs/index.md
@@ -84,6 +84,16 @@ See [users & security](reference/03-users_and_security.md).
 
 Supported databases: **MySQL / MariaDB** and **PostgreSQL** (maintained versions).
 
+The entities of the bundle expect the `underscore_number_aware` Doctrine naming strategy (that of the Symfony recipe):
+their indexes reference `snake_case` column names (e.g. `start_date`).
+
+```yaml
+# config/packages/doctrine.yaml
+doctrine:
+    orm:
+        naming_strategy: doctrine.orm.naming_strategy.underscore_number_aware
+```
+
 The bundle registers its own Doctrine migrations (`CleverAge\UiProcessBundle\Migrations`). Run them, then create a
 first user:
 
diff --git a/src/Entity/ProcessSchedule.php b/src/Entity/ProcessSchedule.php
index 34f7234..f297de4 100644
--- a/src/Entity/ProcessSchedule.php
+++ b/src/Entity/ProcessSchedule.php
@@ -76,7 +76,7 @@ public function setProcess(string $process): static
      */
     public function getContext(): array
     {
-        return \is_array($this->context) ? $this->context : json_decode($this->context);
+        return \is_array($this->context) ? $this->context : json_decode($this->context, true);
     }
 
     /**
diff --git a/src/Entity/User.php b/src/Entity/User.php
index 11532f7..91a20be 100644
--- a/src/Entity/User.php
+++ b/src/Entity/User.php
@@ -136,7 +136,7 @@ public function setLocale(?string $locale): self
 
     public function getRoles(): array
     {
-        return array_merge(['ROLE_USER'], $this->roles);
+        return array_values(array_unique(array_merge(['ROLE_USER'], $this->roles)));
     }
 
     /**
diff --git a/tests/Entity/ProcessScheduleTest.php b/tests/Entity/ProcessScheduleTest.php
index ee989b4..30f8b44 100644
--- a/tests/Entity/ProcessScheduleTest.php
+++ b/tests/Entity/ProcessScheduleTest.php
@@ -72,6 +72,10 @@ public function testGetContextDecodesJsonString(): void
         (new \ReflectionProperty(ProcessSchedule::class, 'context'))->setValue($schedule, '["a","b"]');
 
         self::assertSame(['a', 'b'], $schedule->getContext());
+
+        // A JSON object is decoded as an array (it gave a stdClass: TypeError on the return type)
+        (new \ReflectionProperty(ProcessSchedule::class, 'context'))->setValue($schedule, '{"key":"value"}');
+        self::assertSame(['key' => 'value'], $schedule->getContext());
     }
 
     /**
diff --git a/tests/Entity/UserTest.php b/tests/Entity/UserTest.php
index 6ddbf4a..d030b08 100644
--- a/tests/Entity/UserTest.php
+++ b/tests/Entity/UserTest.php
@@ -69,6 +69,14 @@ public function testGettersAndSetters(): void
         self::assertNull($user->getToken());
     }
 
+    public function testRoleUserIsNotDuplicated(): void
+    {
+        // As stored by UserCreateCommand
+        $user = (new User())->setRoles(['ROLE_USER', 'ROLE_ADMIN']);
+
+        self::assertSame(['ROLE_USER', 'ROLE_ADMIN'], $user->getRoles());
+    }
+
     public function testUserIdentifierRequiresAnEmail(): void
     {
         $user = (new User())->setEmail('');