diff --git a/nur_src/cli/Application.php b/nur_src/cli/Application.php
index 2ad278d..a3d3b80 100644
--- a/nur_src/cli/Application.php
+++ b/nur_src/cli/Application.php
@@ -12,8 +12,8 @@ use nur\path;
 use nur\sery\app\app;
 use nur\sery\output\log as nlog;
 use nur\sery\output\msg as nmsg;
-use nur\sery\output\say as nsay;
-use nur\sery\output\std\StdMessenger as nStdMessenger;
+use nur\sery\output\console as nconsole;
+use nur\sery\output\std\StdMessenger;
 
 /**
  * Class Application: application de base
@@ -43,6 +43,9 @@ abstract class Application {
   const VARDIR = null;
   const LOGDIR = null;
 
+  /** @var bool faut-il activer automatiquement l'écriture dans les logs */
+  const USE_LOGFILE = null;
+
   /** @var bool faut-il maintenir un fichier de suivi du process? */
   const USE_RUNFILE = false;
 
@@ -55,20 +58,16 @@ abstract class Application {
   const USE_RUNLOCK = false;
 
   protected static function _app_init(): void {
-    app::init(static::class);
-
     config::set_fact(config::FACT_CLI_APP);
 
-    nmsg::set_messenger_class(nStdMessenger::class);
-    nmsg::reset_params(["min_level" => nmsg::DEBUG]);
-
+    # avant que l'application soit configurée, configurer le mode debug
     msg::set_messenger_class(Console::class);
     msg::get()->setParametrableParams([
       # En ligne de commande, on peut afficher les messages loggués
       "display_log" => true,
     ]);
-    # avant que l'application soit configurée, rester en mode debug
     msg::get()->setLevels(msg::DEBUG_LEVELS, msg::DEBUG_LEVELS, msg::DEBUG);
+
     # si un fichier nommé .default-profile-devel existe dans le répertoire de
     # l'application ou du projet, alors le profil par défaut est devel
     global $argv;
@@ -85,6 +84,11 @@ abstract class Application {
       $projdir = path::dirname($projdir);
       if ($projdir == "/") break;
     }
+
+    app::init(static::class);
+    nmsg::set_messenger(new StdMessenger([
+      "min_level" => nmsg::DEBUG,
+    ]));
   }
 
   protected static function _app_configure(Application $app): void {
@@ -92,7 +96,18 @@ abstract class Application {
     # revenir à la configuration par défaut une fois que la configuration
     # initiale est faite
     msg::get()->setLevels(msg::PRINT_LEVELS, msg::LOG_LEVELS, msg::TYPE_LEVELS);
-    nsay::reset_params(["min_level" => nmsg::NORMAL]);
+
+    $msgs = ["console" => new StdMessenger([
+      "min_level" => nmsg::NORMAL,
+    ])];
+    if (static::USE_LOGFILE) {
+      $msgs["log"] = new StdMessenger([
+        "output" => app::get()->getLogfile(),
+        "min_level" => nmsg::MINOR,
+        "add_date" => true,
+      ]);
+    }
+    nmsg::init($msgs);
 
     $app->parseArgs();
     config::configure();
@@ -213,7 +228,7 @@ abstract class Application {
 
   static function set_application_verbosity(string $verbosity): void {
     $msg = msg::get();
-    $nsay = nsay::get();
+    $nconsole = nconsole::get();
     switch ($verbosity) {
     case "s":
     case "silent":
@@ -222,7 +237,7 @@ abstract class Application {
         msg::TECH => msg::NEVER,
         msg::EXCEPTION => msg::NEVER,
       ]);
-      $nsay->resetParams([
+      $nconsole->resetParams([
         "min_level" => nmsg::NONE,
       ]);
       break;
@@ -233,7 +248,7 @@ abstract class Application {
         msg::TECH => msg::CRITICAL,
         msg::EXCEPTION => msg::NEVER,
       ]);
-      $nsay->resetParams([
+      $nconsole->resetParams([
         "min_level" => nmsg::MAJOR,
       ]);
       break;
@@ -244,7 +259,7 @@ abstract class Application {
         msg::TECH => msg::MAJOR,
         msg::EXCEPTION => msg::NEVER,
       ]);
-      $nsay->resetParams([
+      $nconsole->resetParams([
         "min_level" => nmsg::MAJOR,
       ]);
       break;
@@ -255,7 +270,7 @@ abstract class Application {
         msg::TECH => msg::MINOR,
         msg::EXCEPTION => msg::NEVER,
       ]);
-      $nsay->resetParams([
+      $nconsole->resetParams([
         "min_level" => nmsg::MINOR,
       ]);
       break;
@@ -267,7 +282,7 @@ abstract class Application {
         msg::TECH => msg::MINOR,
         msg::EXCEPTION => msg::NORMAL,
       ], null, msg::DEBUG);
-      $nsay->resetParams([
+      $nconsole->resetParams([
         "min_level" => nmsg::DEBUG,
       ]);
       break;
@@ -279,7 +294,7 @@ abstract class Application {
         msg::TECH => msg::MINOR,
         msg::EXCEPTION => msg::MINOR,
       ], null, msg::DEBUG);
-      $nsay->resetParams([
+      $nconsole->resetParams([
         "min_level" => nmsg::DEBUG,
       ]);
       break;
@@ -296,14 +311,14 @@ abstract class Application {
     msg::get()->setParametrableParams(["log_output" => $logfile]);
     nlog::create_or_reset_params([
       "output" => $logfile,
-    ], nStdMessenger::class, [
+    ], StdMessenger::class, [
       "add_date" => true,
       "min_level" => nlog::MINOR,
     ]);
   }
   static function set_application_color(bool $color): void {
     msg::get()->setParametrableParams(["color" => $color]);
-    nsay::reset_params([
+    nconsole::reset_params([
       "color" => $color,
     ]);
   }
diff --git a/src/app/app.php b/src/app/app.php
index 336c439..a3eb7d4 100644
--- a/src/app/app.php
+++ b/src/app/app.php
@@ -2,8 +2,8 @@
 namespace nur\sery\app;
 
 use nur\cli\Application;
-use nur\os;
 use nur\sery\os\path;
+use nur\sery\os\sh;
 use nur\sery\ValueException;
 
 class app {
@@ -27,6 +27,8 @@ class app {
       $etcdir = constant("$app::ETCDIR");
       $vardir = constant("$app::VARDIR");
       $logdir = constant("$app::LOGDIR");
+    } elseif (is_array($app)) {
+      return new static($app);
     } else {
       throw ValueException::invalid_type($app, Application::class);
     }
@@ -202,7 +204,9 @@ class app {
   }
 
   function getVarfile(string $name, $profile=null): string {
-    return $this->withProfile($this->fencedJoin($this->vardir, $name), $profile);
+    $file = $this->withProfile($this->fencedJoin($this->vardir, $name), $profile);
+    sh::mkdirof($file);
+    return $file;
   }
 
   protected string $logdir;
@@ -211,8 +215,11 @@ class app {
     return $this->logdir;
   }
 
-  function getLogfile(string $name, $profile=null): string {
-    return $this->withProfile($this->fencedJoin($this->logdir, $name), $profile);
+  function getLogfile(?string $name=null, $profile=null): string {
+    if ($name === null) $name = "{$this->name}.log";
+    $file = $this->withProfile($this->fencedJoin($this->logdir, $name), $profile);
+    sh::mkdirof($file);
+    return $file;
   }
 
   /**
@@ -233,7 +240,7 @@ class app {
       $file = path::reljoin($this->datadir, $file);
     }
     $file = $this->withProfile($file, $profile);
-    if ($ensureDir) os::mkdirof($file);
+    if ($ensureDir) sh::mkdirof($file);
     return $file;
   }
 
diff --git a/src/output/_messenger.php b/src/output/_messenger.php
index e24ed09..c5dc808 100644
--- a/src/output/_messenger.php
+++ b/src/output/_messenger.php
@@ -1,44 +1,39 @@
 <?php
 namespace nur\sery\output;
 
+use nur\sery\cl;
 use nur\sery\str;
+use nur\sery\ValueException;
 
 /**
  * Class _messenger: classe de base pour say, log et msg
  */
 abstract class _messenger {
-  /** @var IMessenger */
-  protected static $say;
-
-  /** @var IMessenger */
-  protected static $log;
-
+  abstract static function is_setup(): bool;
+  abstract static function set_messenger(IMessenger $msg);
   abstract static function get(): IMessenger;
 
+  static function set_messenger_class(string $msg_class, ?array $params=null) {
+    if (!is_subclass_of($msg_class, IMessenger::class)) {
+      throw ValueException::invalid_class($msg_class, IMessenger::class);
+    }
+    static::set_messenger(new $msg_class($params));
+  }
+
+  static function create_or_reset_params(?array $params=null, string $log_class=null, ?array $create_params=null) {
+    if (static::is_setup()) {
+      self::reset_params($params);
+    } else {
+      $params = cl::merge($params, $create_params);
+      self::set_messenger_class($log_class, $params);
+    }
+  }
+
   /** obtenir une nouvelle instance, avec un nouveau paramétrage */
   static function new(?array $params=null): IMessenger {
     return static::get()->clone($params);
   }
 
-  /** @var IMessenger */
-  protected static $msg;
-
-  /** @var IMessenger[] */
-  protected static $stack;
-
-  /** pousser une nouvelle instance avec un nouveau paramétrage sur la pile */
-  static function push(?array $params=null) {
-    self::$stack[] = static::get();
-    self::$msg = self::new($params);
-  }
-
-  /** dépiler la précédente instance */
-  static function pop(): IMessenger {
-    if (self::$stack) $msg = self::$msg = array_pop(self::$stack);
-    else $msg = self::$msg;
-    return $msg;
-  }
-
   static final function __callStatic($name, $args) {
     $name = str::us2camel($name);
     call_user_func_array([static::get(), $name], $args);
diff --git a/src/output/console.php b/src/output/console.php
new file mode 100644
index 0000000..bdcd612
--- /dev/null
+++ b/src/output/console.php
@@ -0,0 +1,29 @@
+<?php
+namespace nur\sery\output;
+
+use nur\sery\output\std\ProxyMessenger;
+use nur\sery\ValueException;
+
+/**
+ * Class console: afficher un message sur la console
+ *
+ * Cette classe DOIT être initialisée avant d'être utilisée
+ */
+class console extends _messenger {
+  private static ?IMessenger $msg = null;
+
+  private static bool $setup = false;
+
+  static function is_setup(): bool {
+    return self::$setup;
+  }
+
+  static function set_messenger(IMessenger $msg) {
+    self::$msg = $msg;
+    self::$setup = true;
+  }
+
+  static function get(): IMessenger {
+    return self::$msg ??= new ProxyMessenger();
+  }
+}
diff --git a/src/output/log.php b/src/output/log.php
index 3b4bab6..0c9b22a 100644
--- a/src/output/log.php
+++ b/src/output/log.php
@@ -8,42 +8,23 @@ use nur\sery\ValueException;
 /**
  * Class log: inscrire un message dans les logs uniquement
  *
- * Cette classe (ou la classe parallèle {@link msg} DOIT être initialisée avant
- * d'être utilisée
+ * Cette classe DOIT être initialisée avant d'être utilisée
  */
 class log extends _messenger {
-  static function set_messenger(IMessenger $log=null) {
-    self::$log = $log;
-    // forcer la recréation de l'instance partagée $msg
-    self::$msg = null;
+  private static ?IMessenger $msg = null;
+
+  private static bool $setup = false;
+
+  static function is_setup(): bool {
+    return self::$setup;
   }
 
-  static function set_messenger_class(string $log_class=null, ?array $params=null) {
-    if (!is_subclass_of($log_class, IMessenger::class)) {
-      throw ValueException::invalid_class($log_class, IMessenger::class);
-    }
-    self::set_messenger(new $log_class($params));
+  static function set_messenger(IMessenger $msg) {
+    self::$msg = $msg;
+    self::$setup = true;
   }
 
   static function get(): IMessenger {
-    if (self::$msg === null) {
-      $msg = self::$log;
-      if ($msg === null) $msg = new ProxyMessenger();
-      self::$msg = $msg;
-    }
-    return self::$msg;
-  }
-
-  static function have_log(): bool {
-    return self::$log !== null;
-  }
-
-  static function create_or_reset_params(?array $params=null, string $log_class=null, ?array $create_params=null) {
-    if (self::$log === null) {
-      $params = cl::merge($params, $create_params);
-      self::set_messenger_class($log_class, $params);
-    } else {
-      self::reset_params($params);
-    }
+    return self::$msg ??= new ProxyMessenger();
   }
 }
diff --git a/src/output/msg.php b/src/output/msg.php
index 7ba5f77..14e48d5 100644
--- a/src/output/msg.php
+++ b/src/output/msg.php
@@ -2,54 +2,76 @@
 namespace nur\sery\output;
 
 use nur\sery\output\std\ProxyMessenger;
+use nur\sery\php\func;
 use nur\sery\ValueException;
 
 /**
  * Class msg: inscrire un message dans les logs ET l'afficher sur la console
  *
  * Cette classe DOIT être initialisée avec {@link set_messenger()} ou
- * {@link set_messenger_class()} avant d'être utilisée. Une fois initialisée,
- * les classes {@link say} et {@link log} sont utilisables aussi
+ * {@link set_messenger_class()} avant d'être utilisée.
  */
 class msg extends _messenger {
-  static function set_messenger(?IMessenger $say, ?IMessenger $log=null) {
-    if ($say !== null) self::$say = $say;
-    if ($log !== null) self::$log = $log;
-    if ($say !== null || $log !== null) {
-      // forcer la recréation de l'instance partagée $msg
-      self::$msg = null;
-    }
+  private static ?IMessenger $msg = null;
+
+  private static bool $setup = false;
+
+  static function is_setup(): bool {
+    return self::$setup;
   }
 
-  static function set_messenger_class(?string $say_class, ?string $log_class=null) {
-    if ($say_class !== null) {
-      if (!is_subclass_of($say_class, IMessenger::class)) {
-        throw ValueException::invalid_class($say_class, IMessenger::class);
-      }
-      self::$say = new $say_class();
-    }
-    if ($log_class !== null) {
-      if (!is_subclass_of($log_class, IMessenger::class)) {
-        throw ValueException::invalid_class($log_class, IMessenger::class);
-      }
-      self::$log = new $log_class();
-    }
-    if ($say_class !== null || $log_class !== null) {
-      // forcer la recréation de l'instance partagée $msg
-      self::$msg = null;
-    }
+  static function set_messenger(IMessenger $msg) {
+    self::$msg = $msg;
+    self::$setup = true;
   }
 
   static function get(): IMessenger {
-    if (self::$msg === null) {
-      $log = self::$log;
-      $say = self::$say;
-      if ($log !== null && $say !== null) $msg = new ProxyMessenger($log, $say);
-      elseif ($log !== null) $msg = $log;
-      elseif ($say !== null) $msg = $say;
-      else $msg = new ProxyMessenger();
-      self::$msg = $msg;
+    return self::$msg ??= new ProxyMessenger();
+  }
+
+  /**
+   * initialiser les instances say, console, log. 
+   */
+  static function init(array $msgs) {
+    $say = $msgs["say"] ?? null;
+    $console = $msgs["console"] ?? null;
+    $log = $msgs["log"] ?? null;
+    $msgs = [];
+    if ($log !== null && $log !== false) {
+      if ($log instanceof IMessenger) log::set_messenger($log);
+      elseif (is_string($log)) log::set_messenger_class($log);
+      elseif (is_array($log)) {
+        func::ensure_class($log, $args);
+        $log = func::cons($log, $args);
+      }
+      log::set_messenger($log);
+      $msgs[] = $log;
     }
-    return self::$msg;
+    if ($console !== null && $console !== false) {
+      if ($console instanceof IMessenger) console::set_messenger($console);
+      elseif (is_string($console)) console::set_messenger_class($console);
+      elseif (is_array($console)) {
+        func::ensure_class($console, $args);
+        $console = func::cons($console, $args);
+      }
+      console::set_messenger($console);
+      $msgs[] = $console;
+    }
+    if ($say !== null && $say !== false) {
+      if ($say instanceof IMessenger) say::set_messenger($say);
+      elseif (is_string($say)) say::set_messenger_class($say);
+      elseif (is_array($say)) {
+        func::ensure_class($say, $args);
+        $say = func::cons($say, $args);
+      }
+      say::set_messenger($say);
+      $msgs[] = $say;
+    }
+    if ($say === null && $console !== null) {
+      say::set_messenger($console);
+    } elseif ($console === null && $say !== null) {
+      console::set_messenger($say);
+    }
+    self::set_messenger(new ProxyMessenger(...$msgs));
   }
 }
diff --git a/src/output/say.php b/src/output/say.php
index 6bf13e2..312b241 100644
--- a/src/output/say.php
+++ b/src/output/say.php
@@ -5,31 +5,25 @@ use nur\sery\output\std\ProxyMessenger;
 use nur\sery\ValueException;
 
 /**
- * Class say: afficher un message sur la console uniquement
+ * Class say: afficher un message pour l'utilisateur
  *
- * Cette classe (ou la classe parallèle {@link msg} DOIT être initialisée avant
- * d'être utilisée
+ * Cette classe DOIT être initialisée avant d'être utilisée
  */
 class say extends _messenger {
-  static function set_messenger(IMessenger $say) {
-    self::$say = $say;
-    // forcer la recréation de l'instance partagée $msg
-    self::$msg = null;
+  private static ?IMessenger $msg = null;
+
+  private static bool $setup = false;
+
+  static function is_setup(): bool {
+    return self::$setup;
   }
 
-  static function set_messenger_class(string $say_class, ?array $params=null) {
-    if (!is_subclass_of($say_class, IMessenger::class)) {
-      throw ValueException::invalid_class($say_class, IMessenger::class);
-    }
-    self::set_messenger(new $say_class($params));
+  static function set_messenger(IMessenger $msg) {
+    self::$msg = $msg;
+    self::$setup = true;
   }
 
   static function get(): IMessenger {
-    if (self::$msg === null) {
-      $msg = self::$say;
-      if ($msg === null) $msg = new ProxyMessenger();
-      self::$msg = $msg;
-    }
-    return self::$msg;
+    return self::$msg ??= new ProxyMessenger();
   }
 }
diff --git a/src/php/func.php b/src/php/func.php
index 10e3198..a8bbe78 100644
--- a/src/php/func.php
+++ b/src/php/func.php
@@ -418,6 +418,18 @@ class func {
     return false;
   }
 
+  /**
+   * Comme {@link check_class()} mais lance une exception si la classe est
+   * invalide
+   *
+   * @throws ValueException si $class n'est pas une classe valide
+   */
+  static final function ensure_class(&$class, &$args=null): void {
+    if (!self::check_class($class, $args)) {
+      throw ValueException::invalid_type($class, "class");
+    }
+  }
+
   /**
    * Instancier la classe avec les arguments spécifiés.
    * Adapter $args en fonction du nombre réel d'arguments du constructeur