diff --git a/src/EnvReader/EnvConfig.php b/src/EnvReader/EnvConfig.php
index e52dd2d..22282cb 100644
--- a/src/EnvReader/EnvConfig.php
+++ b/src/EnvReader/EnvConfig.php
@@ -11,12 +11,12 @@ abstract class EnvConfig extends GenericConfig implements IExternalConfigFile {
     protected function readConfig (): void {
         $configFile = $this->getConfigFilePath();
         if (!file_exists($configFile)) {
-            return;
+            throw new Exception('Unable to find configuration file "' . $configFile . '"');
         }
 
         $lines = file($configFile, FILE_IGNORE_NEW_LINES | FILE_SKIP_EMPTY_LINES);
         if ($lines === false) {
-            throw new Exception('Unable to read environment file "' . $configFile . '"');
+            throw new Exception('Unable to read configuration file "' . $configFile . '"');
         }
 
         foreach ($lines as $line) {
diff --git a/src/EnvReader/GenericConfig.php b/src/EnvReader/GenericConfig.php
index f4b539c..4e7453d 100644
--- a/src/EnvReader/GenericConfig.php
+++ b/src/EnvReader/GenericConfig.php
@@ -43,9 +43,7 @@ abstract class GenericConfig {
      * @noinspection PhpReturnDocTypeMismatchInspection
      */
     protected function initialProperties () {
-        return [
-            'APP_DEV' => 0,
-        ];
+        return [];
     }
     /**
      * Read the configuration file
@@ -77,15 +75,15 @@ abstract class GenericConfig {
     /**
      * Get a property value
      *
-     * @param string      $name    The property name
-     * @param string|null $default The default value if property is not set
-     *                             Raise an exception if property is not set AND $default is Null
+     * @param string $name    The property name
+     * @param mixed  $default The default value if property is not set
+     *                        Raise an exception if property is not set AND $default is Null
      *
-     * @return string The property value
+     * @return mixed The property value
      *
      * @throws UnexpectedValueException If property is not set AND $default is Null
      */
-    public function getProperty (string $name, ?string $default = null): string {
+    public function getProperty (string $name, $default = null) {
         if (!$this->hasProperty($name)) {
             if ($default === null) {
                 throw new UnexpectedValueException('The "' . $name . '" property is not set');
diff --git a/src/EnvReader/TMultiLevelProperties.php b/src/EnvReader/TMultiLevelProperties.php
new file mode 100644
index 0000000..5a0ad2e
--- /dev/null
+++ b/src/EnvReader/TMultiLevelProperties.php
@@ -0,0 +1,82 @@
+<?php
+
+namespace jrosset\EnvReader;
+
+use jrosset\ArrayClasses\IArrayClass;
+use jrosset\ArrayClasses\ImmutableArrayClass;
+use UnexpectedValueException;
+
+/**
+ * Trait for multi-level properties
+ */
+trait TMultiLevelProperties {
+    /**
+     * @inheritDoc
+     */
+    public function hasProperty (string $name): bool {
+        $levels = $this->getPropertyLevels($name);
+
+        $value = $this->getProperties();
+        foreach ($levels as $level) {
+            if ($value instanceof IArrayClass) {
+                if (!$value->has($level)) {
+                    return false;
+                }
+                $value = $value->get($level);
+            }
+            else {
+                if (!isset($value[$level])) {
+                    return false;
+                }
+                $value = $value[$level];
+            }
+        }
+
+        return true;
+    }
+    /**
+     * @inheritDoc
+     */
+    public function getProperty (string $name, $default = null) {
+        if (!$this->hasProperty($name)) {
+            if ($default === null) {
+                throw new UnexpectedValueException('The "' . $name . '" property is not set');
+            }
+            return $default;
+        }
+
+        $levels = $this->getPropertyLevels($name);
+
+        $value = $this->getProperties();
+        foreach ($levels as $level) {
+            if ($value instanceof IArrayClass) {
+                $value = $value->get($level);
+            }
+            else {
+                $value = $value[$level];
+            }
+        }
+
+        return $value;
+    }
+    /**
+     * Provide the multi-level separator
+     *
+     * Reimplements to override
+     *
+     * @return string The separator
+     */
+    protected function getPropertySeparator (): string {
+        return '/';
+    }
+    /**
+     * Get array of levels of a property name
+     *
+     * @param string $propertyName The property name
+     *
+     * @return ImmutableArrayClass The property levels
+     */
+    private function getPropertyLevels (string $propertyName): ImmutableArrayClass {
+        return new ImmutableArrayClass(explode($this->getPropertySeparator(), $propertyName));
+    }
+}
\ No newline at end of file