diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 12e8443..b5441f5 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -16,5 +16,8 @@ jobs:
         run: |
           python -m pip install --upgrade pip
           uv tool install ruff
+          uv tool install pytest
       - name: Run Ruff
-        run: uvx ruff check --output-format=github .
\ No newline at end of file
+        run: uvx ruff check --output-format=github .
+      - name: Run tests
+        run: uvx pytest --maxfail=1 --disable-warnings -q
\ No newline at end of file
diff --git a/pyproject.toml b/pyproject.toml
index f602780..a199642 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,9 @@ version = "0.1.0"
 description = "Homeworks"
 readme = "README.md"
 requires-python = ">=3.13.7"
-dependencies = []
+dependencies = [
+    "pytest>=8.4.2",
+]
 
 [tool.ruff]
 exclude = [
@@ -59,4 +61,4 @@ extend-select = [
 quote-style = "double"
 indent-style = "space"
 skip-magic-trailing-comma = false
-line-ending = "auto"
\ No newline at end of file
+line-ending = "auto"
diff --git a/src/17oct25/heap_sort.py b/src/17oct25/heap_sort.py
new file mode 100644
index 0000000..4de48ae
--- /dev/null
+++ b/src/17oct25/heap_sort.py
@@ -0,0 +1,18 @@
+def heap(collection, index, length):
+    head = index
+    if index * 2 + 1 < length and collection[head] < collection[index * 2 + 1]:
+        head = index * 2 + 1
+    if index * 2 + 2 < length and collection[head] < collection[index * 2 + 2]:
+        head = index * 2 + 2
+    if head != index:
+        collection[index], collection[head] = collection[head], collection[index]
+        heap(collection, head, length)
+
+def heap_sort(collection):
+    n = len(collection)
+    for i in range(n // 2, -1, -1):
+        heap(collection, i, n)
+    for i in range(n - 1, 0, -1):
+        collection[i], collection[0] = collection[0], collection[i]
+        heap(collection, 0, i)
+    return collection
diff --git a/src/17oct25/test_heap_sort.py b/src/17oct25/test_heap_sort.py
new file mode 100644
index 0000000..a79f59f
--- /dev/null
+++ b/src/17oct25/test_heap_sort.py
@@ -0,0 +1,55 @@
+import random
+
+import pytest
+from heap_sort import heap_sort
+
+
+def test_simple():
+    assert heap_sort([3, 2, 1, 5, 10, 8]) == [1, 2, 3, 5, 8, 10]
+
+def test_short_list():
+    assert heap_sort([42, 0]) == [0, 42]
+
+def test_long_list():
+    a = [93, 49, 39, 24, 69, 72, 90, 38, 55, 24, 63, 23, 39, 84, 35, 68, 80, 17, 12, 94, 69, 37, 97, 89, 16, 53, 96, 13]
+    b = [12, 13, 16, 17, 23, 24, 24, 35, 37, 38, 39, 39, 49, 53, 55, 63, 68, 69, 69, 72, 80, 84, 89, 90, 93, 94, 96, 97]
+    heap_sort(a)
+    assert a == b
+
+def test_list_of_strings():
+    assert heap_sort(["p", "y", "t", "h", "o", "n"]) == ['h', 'n', 'o', 'p', 't', 'y']
+
+def test_self():
+    assert heap_sort([40, 8, 25, 9, 37, 23, 41, 18, 35, 24]) == heap_sort([40, 8, 25, 9, 37, 23, 41, 18, 35, 24])
+
+@pytest.mark.parametrize(
+    ["input_data", "expected_out"],
+    [
+        ([1, 3, 2], [1, 2, 3]),
+        ([10**10, 10**9, 10**5, 10**8, 10**2, 10**7], [10**2, 10**5, 10**7, 10**8, 10**9, 10**10]),
+        ([651, -86, -152, 384, 245, 428, -29, -839, -575, -472], [-839, -575, -472, -152, -86, -29, 245, 384, 428, 651]),
+        ([313, 665, -641, -435, -819, -420, 801, 208], [-819, -641, -435, -420, 208, 313, 665, 801]),
+        ([-5505, 9828, 9045, 969, 1508, -8066, -8690], [-8690, -8066, -5505, 969, 1508, 9045, 9828]),
+        ([-35.120, 28.864, 54.075, -5.354, 57.778, 43.898], [-35.120, -5.354, 28.864, 43.898, 54.075, 57.778]),
+        ([1.3, 1.2, 1.1, 1.0], [1.0, 1.1, 1.2, 1.3]),
+    ]
+)
+def test_another(input_data, expected_out):
+    assert heap_sort(input_data) == expected_out
+
+@pytest.mark.xfail(raises=TypeError)
+def test_incorrect_type():
+    assert heap_sort(1)
+
+def test_empty_list():
+    assert heap_sort([]) == []
+
+@pytest.fixture()
+def random_int_list():
+    return random.sample(range(-200, 200), 150)
+
+def test_property_python_sort(random_int_list):
+    a = sorted(random_int_list)
+    b = heap_sort(random_int_list)
+    assert a == b
+
diff --git a/src/__init__.py b/src/__init__.py
new file mode 100644
index 0000000..e69de29