diff --git a/minigrida/cvgenerators/__init__.py b/minigrida/cvgenerators/__init__.py
index e69de29..c9840bc 100644
--- a/minigrida/cvgenerators/__init__.py
+++ b/minigrida/cvgenerators/__init__.py
@@ -0,0 +1 @@
+from .generic import *
diff --git a/minigrida/cvgenerators/generic.py b/minigrida/cvgenerators/generic.py
new file mode 100644
index 0000000..43f8403
--- /dev/null
+++ b/minigrida/cvgenerators/generic.py
@@ -0,0 +1,25 @@
+#!/usr/bin/env python
+# file generic.py
+# author Florent Guiotte <florent.guiotte@irisa.fr>
+# version 0.0
+# date 08 juil. 2020
+"""Abstract
+
+doc.
+"""
+
+from sklearn.model_selection import GroupKFold, StratifiedShuffleSplit
+
+
+class GroupStratifiedShuffleSplit(GroupKFold):
+    def __init__(self, n_splits=5, train_size=None, random_state=None):
+        super().__init__(n_splits)
+        self.train_size = train_size
+        self.random_state = random_state
+    
+    def split(self, X, y=None, groups=None):
+        splits = [s for s in super().split(X, y, groups)]
+        for train, test in splits:
+            sss_train, sss_test = next(StratifiedShuffleSplit(1, train_size=self.train_size, random_state=self.random_state).split(X[train], y[train], groups[train]))
+            
+            yield sss_train, test