diff --git a/CHANGELOG.md b/CHANGELOG.md
index 501807a5..47d8ab80 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,9 @@
 
 ## v1.1.x
 
+- Add generics templating from
+  - https://gpb.moe/doc/slides/Gestion_Erreur_Toutes_Ses_Couleurs_FR.pdf
+  - https://slides.com/kpn13/les-generiques-en-php
 - Add Flow\Driver\RevoltDriver
 - Add more quality tools from https://github.com/IngeniozIT/php-skeleton
 
diff --git a/examples/generic-errors.php b/examples/generic-errors.php
new file mode 100644
index 00000000..85e66c0a
--- /dev/null
+++ b/examples/generic-errors.php
@@ -0,0 +1,108 @@
+<?php
+
+declare(strict_types=1);
+
+require __DIR__ . '/../vendor/autoload.php';
+
+// https://gpb.moe/doc/slides/Gestion_Erreur_Toutes_Ses_Couleurs_FR.pdf
+// https://psalm.dev/r/dd8e8f59fe
+
+/**
+ * @template T1
+ * @template E1
+ */
+class Wrapper
+{
+    /**
+     * @param T1 $value
+     * @param E1 $err
+     */
+    public function __construct(
+        public mixed $value,
+        public mixed $err,
+        public bool $isErr = false,
+    ) {
+    }
+
+    /**
+     * @template T2
+     * @template E2
+     *
+     * @param callable(T1): Wrapper<T2, E2> $f
+     *
+     * @return Wrapper<T2, E1|E2>
+     */
+    public function bind($f): self
+    {
+        if ($this->isErr) {
+            // @var Wrapper<T2, E1> Shut up Psalm
+            return $this;
+        }
+
+        return $f($this->value);
+    }
+}
+
+enum OpenFileErrors
+{
+    case FileDoesNotExist;
+    case AccessDenied;
+    case IsDirectory;
+}
+
+class File
+{
+}
+
+enum GetContentErrors
+{
+    case E1;
+    case E2;
+}
+
+enum ParseContentErrors
+{
+    case E1;
+    case E2;
+}
+
+class UnparsedOutput
+{
+}
+class ParsedOutput
+{
+}
+
+/** @return Wrapper<File, OpenFileErrors> */
+function open_file(string $path): Wrapper
+{
+    return new Wrapper(new File(), OpenFileErrors::FileDoesNotExist);
+}
+
+/** @return Wrapper<UnparsedOutput, GetContentErrors> */
+function get_content_file(File $f): Wrapper
+{
+    return new Wrapper(new UnparsedOutput(), GetContentErrors::E1);
+}
+/** @return Wrapper<ParsedOutput, ParseContentErrors> */
+function parse_content(UnparsedOutput $f): Wrapper
+{
+    return new Wrapper(new ParsedOutput(), ParseContentErrors::E1);
+}
+
+$data = open_file('')
+    ->bind(get_content_file(...))
+    ->bind(parse_content(...))
+;
+$result = match ($data->isErr) {
+    true => match ($data->err) {
+        OpenFileErrors::FileDoesNotExist => 1,
+        OpenFileErrors::AccessDenied => 2,
+        OpenFileErrors::IsDirectory => 3,
+        GetContentErrors::E1 => 4,
+        GetContentErrors::E2 => 5,
+        ParseContentErrors::E1 => 6,
+        ParseContentErrors::E2 => 7,
+    },
+    false => $data->value,
+};
diff --git a/src/DriverInterface.php b/src/DriverInterface.php
index cec2ccc4..2e3075a2 100644
--- a/src/DriverInterface.php
+++ b/src/DriverInterface.php
@@ -6,10 +6,13 @@
 
 use Closure;
 
+/**
+ * @template T of object
+ */
 interface DriverInterface
 {
     /**
-     * @param Closure $onResolve called on resolved and first argument is $callback return or Flow\Exception on Exception
+     * @param callable(ExceptionInterface|?T): void
      *
      * @return Closure when called, this start async $callback
      */
diff --git a/src/Exception/RuntimeException.php b/src/Exception/RuntimeException.php
index 8fc86d6f..60e48dbd 100644
--- a/src/Exception/RuntimeException.php
+++ b/src/Exception/RuntimeException.php
@@ -4,6 +4,7 @@
 
 namespace Flow\Exception;
 
+use Flow\ExceptionInterface;
 use RuntimeException as NativeRuntimeException;
 
 class RuntimeException extends NativeRuntimeException implements ExceptionInterface
diff --git a/src/Exception/ExceptionInterface.php b/src/ExceptionInterface.php
similarity index 79%
rename from src/Exception/ExceptionInterface.php
rename to src/ExceptionInterface.php
index 6fcb1557..74b93f26 100644
--- a/src/Exception/ExceptionInterface.php
+++ b/src/ExceptionInterface.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Flow\Exception;
+namespace Flow;
 
 use Throwable;
 
diff --git a/src/Flow/Flow.php b/src/Flow/Flow.php
index 1b12038c..8f9ed891 100644
--- a/src/Flow/Flow.php
+++ b/src/Flow/Flow.php
@@ -7,7 +7,7 @@
 use Closure;
 use Flow\Driver\ReactDriver;
 use Flow\DriverInterface;
-use Flow\Exception\RuntimeException;
+use Flow\ExceptionInterface;
 use Flow\FlowInterface;
 use Flow\Ip;
 use Flow\IpStrategy\LinearIpStrategy;
@@ -88,12 +88,12 @@ private function nextIpJob(): void
         foreach ($this->jobs as $i => $job) {
             $this->driver->async($job, function (mixed $value) use ($ip, &$count, $i, $callback) {
                 $count--;
-                if ($count === 0 || $value instanceof RuntimeException) {
+                if ($count === 0 || $value instanceof ExceptionInterface) {
                     $count = 0;
                     $this->ipStrategy->done($ip);
                     $this->nextIpJob();
 
-                    if ($value instanceof RuntimeException) {
+                    if ($value instanceof ExceptionInterface) {
                         if (isset($this->errorJobs[$i])) {
                             $this->errorJobs[$i]($ip->data, $value->getPrevious());
                         } else {
diff --git a/src/FlowInterface.php b/src/FlowInterface.php
index 62a21185..766717a7 100644
--- a/src/FlowInterface.php
+++ b/src/FlowInterface.php
@@ -6,9 +6,23 @@
 
 use Closure;
 
+/**
+ * @template T
+ */
 interface FlowInterface
 {
+    /**
+     * @param Ip<T> $ip
+     */
     public function __invoke(Ip $ip, Closure $callback = null): void;
 
+    /**
+     * @template T1 of IP
+     * @template T2 of IP
+     *
+     * @param FlowInterface<T1> $flow
+     *
+     * @return FlowInterface<T2>
+     */
     public function fn(self $flow): self;
 }
diff --git a/src/Ip.php b/src/Ip.php
index 4dd9dc4a..f1390e4f 100644
--- a/src/Ip.php
+++ b/src/Ip.php
@@ -4,8 +4,14 @@
 
 namespace Flow;
 
+/**
+ * @template T of object
+ */
 final readonly class Ip
 {
+    /**
+     * @param ?T $data
+     */
     public function __construct(public ?object $data = null)
     {
     }
diff --git a/tools/php-cs-fixer/.php-cs-fixer.php b/tools/php-cs-fixer/.php-cs-fixer.php
index 3ac3aa32..63b441f5 100644
--- a/tools/php-cs-fixer/.php-cs-fixer.php
+++ b/tools/php-cs-fixer/.php-cs-fixer.php
@@ -33,7 +33,7 @@
             'import_functions' => true,
             'import_classes' => true,
         ],
-        'logical_operators' => false, // https://cs.symfony.com/doc/rules/operator/logical_operators.html we keep or and by design
+        'logical_operators' => false, // https://cs.symfony.com/doc/rules/operator/logical_operators.html prefer use 'or' and 'and' operators by design
         'yoda_style' => false, // https://cs.symfony.com/doc/rules/control_structure/yoda_style.html
         'increment_style' => ['style' => 'post'],
     ])