diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 41c325f..4140ff1 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -24,34 +24,24 @@ repos:
     rev: 6.0.0
     hooks:
       - id: flake8
-  - repo: https://github.com/pre-commit/mirrors-mypy
-    rev: v1.6.1
+  - repo: https://github.com/psf/black
+    rev: 23.11.0
     hooks:
-      - id: mypy
-        verbose: true
-        args: [--show-error-codes, --explicit-package-bases]
-        additional_dependencies: ['types-requests', 'pydantic']
-  # - repo: https://github.com/asottile/reorder_python_imports
-  #   rev: v3.9.0
-  #   hooks:
-  #     - id: reorder-python-imports
-  #       args: [--py37-plus]
+      - id: black
   - repo: https://github.com/asottile/add-trailing-comma
     rev: v2.3.0
     hooks:
       - id: add-trailing-comma
         args: [--py36-plus]
-  - repo: https://github.com/asottile/pyupgrade
-    rev: v3.2.2
+  - repo: https://github.com/astral-sh/ruff-pre-commit
+    rev: v0.1.5
     hooks:
-      - id: pyupgrade
-        args: [--py37-plus]
-  - repo: https://github.com/pre-commit/mirrors-autopep8
-    rev: v2.0.0
+      - id: ruff
+        args: [ --fix ]
+  - repo: https://github.com/pre-commit/mirrors-mypy
+    rev: v1.6.1
     hooks:
-      - id: autopep8
-  # - repo: https://github.com/Zac-HD/shed
-  #   rev: 0.10.7
-  #   hooks:
-  #     - id: shed
-  #       types_or: [python, markdown, rst]
+      - id: mypy
+        verbose: true
+        args: [--show-error-codes, --explicit-package-bases]
+        additional_dependencies: ['types-requests', 'pydantic']
diff --git a/README.md b/README.md
index 6ecd9dc..bd9ea16 100644
--- a/README.md
+++ b/README.md
@@ -33,6 +33,10 @@
 [201507p]: https://adventofcode.com/2015/day/7
 [201508]: https://github.com/Stegallo/adventofcode/blob/master/y_2015/day8.py
 [201508p]: https://adventofcode.com/2015/day/8
+[201509]: https://github.com/Stegallo/adventofcode/blob/master/y_2015/day9.py
+[201509p]: https://adventofcode.com/2015/day/9
+[201510]: https://github.com/Stegallo/adventofcode/blob/master/y_2015/day10.py
+[201510p]: https://adventofcode.com/2015/day/10
 
 ## to run the code
 
diff --git a/tests/y_2015/test_2015_day10.py b/tests/y_2015/test_2015_day10.py
new file mode 100644
index 0000000..431d6c8
--- /dev/null
+++ b/tests/y_2015/test_2015_day10.py
@@ -0,0 +1,32 @@
+from __future__ import annotations
+
+from unittest.mock import mock_open, patch, MagicMock
+
+from y_2015.day10 import Day
+
+with patch("builtins.open", mock_open(read_data="")):
+    day = Day()
+
+
+def test_apply_times():
+    assert day._apply_times("1", 1) == "11"
+    assert day._apply_times("11", 1) == "21"
+
+    assert day._apply_times("1", 2) == "21"
+    assert day._apply_times("1", 3) == "1211"
+    assert day._apply_times("1", 4) == "111221"
+    assert day._apply_times("1", 5) == "312211"
+
+
+def test_calculate_1():
+    day._Day__input_data = ["1"]
+    day._apply_times = MagicMock()
+    day._calculate_1()
+    day._apply_times.assert_called_once_with(["1"], 40)
+
+
+def test_calculate_2():
+    day._Day__input_data = ["1"]
+    day._apply_times = MagicMock()
+    day._calculate_2()
+    day._apply_times.assert_called_once_with(["1"], 50)
diff --git a/y_2015/day10.py b/y_2015/day10.py
new file mode 100644
index 0000000..5d49e76
--- /dev/null
+++ b/y_2015/day10.py
@@ -0,0 +1,39 @@
+from common.aoc import AoCDay
+
+
+class Day(AoCDay):
+    def __init__(self, test=0):
+        super().__init__(__name__, test)
+
+    def _preprocess_input(self):
+        self.__input_data = self._input_data[0][0]
+
+    def say_loud(self, x: str) -> str:
+        if len(x) == 1:
+            return f"1{x[0]}"
+        chunks = []
+        chunk = [x[0]]
+        for c in range(len(x)):
+            if c == 0:
+                continue
+
+            if x[c - 1] == x[c]:
+                chunk.append(x[c])
+            else:
+                chunks.append(chunk)
+                chunk = [x[c]]
+        chunks.append(chunk)
+        k = [str(len(i)) + i[0] for i in chunks]
+        return "".join(k)
+
+    def _apply_times(self, input: str, times: int) -> str:
+        result = input
+        for _ in range(times):
+            result = self.say_loud(result)
+        return result
+
+    def _calculate_1(self):
+        return len(self._apply_times(self.__input_data, 40))
+
+    def _calculate_2(self):
+        return len(self._apply_times(self.__input_data, 50))