diff --git a/.github/workflows/tests.yaml b/.github/workflows/tests.yaml
new file mode 100644
index 0000000..cef489a
--- /dev/null
+++ b/.github/workflows/tests.yaml
@@ -0,0 +1,25 @@
+name: tests
+
+on: [push, pull_request]
+
+jobs:
+  pytest:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: ["3.8", "3.9", "3.10"]
+
+    steps:
+    - uses: actions/checkout@v3
+    - name: Set up Python ${{ matrix.python-version }}
+      uses: actions/setup-python@v4
+      with:
+        python-version: ${{ matrix.python-version }}
+    - name: Install dependencies
+      run: |
+        python -m pip install --upgrade pip
+        pip install .[tests]
+    - name: Test with pytest
+      run: |
+        pytest -v
diff --git a/README.rst b/README.rst
deleted file mode 100644
index 44d1744..0000000
--- a/README.rst
+++ /dev/null
@@ -1,54 +0,0 @@
-Markdown-Include
-================
-
-This is an extension to
-`Python-Markdown <https://pythonhosted.org/Markdown/>`__ which provides
-an "include" function, similar to that found in LaTeX (and also the C
-pre-processor and Fortran). I originally wrote it for my
-`FORD <https://pypi.python.org/pypi/FORD>`__ Fortran auto-documentation
-generator.
-
-Installation
-------------
-
-This module can now be installed using ``pip``.
-
-::
-
-    pip install markdown-include
-
-Usage
------
-
-This module can be used in a program in the following way:
-
-::
-
-    import markdown
-    html = markdown.markdown(source, extensions=[markdown_include.include'])
-
-The syntax for use within your Markdown files is ``{!filename!}``. This
-statement will be replaced by the contents of ``filename``.
-Markdown-Include will work recursively, so any included files within
-``filename`` wil also be included. This replacement is done prior to any
-other Markdown processing, so any Markdown syntax that you want can be used
-within your included files. Note that this is a change from the previous 
-version. It was felt that this syntax was less likely to conflict with any code
-fragments present in the Markdown.
-
-By default, all file-names are evaluated relative to the location from
-which Markdown is being called. If you would like to change the
-directory relative to which paths are evaluated, then this can be done
-by specifying the extension setting ``base_path``.
-
-::
-
-    import markdown
-    from markdown_include.include import MarkdownInclude
-
-    # Markdown Extensions
-    markdown_include = MarkdownInclude(
-        configs={'base_path':'/srv/content/', 'encoding': 'iso-8859-1'}
-    )
-    html = markdown.markdown(source, extensions=[markdown_include])
-
diff --git a/pyproject.toml b/pyproject.toml
index c13bb83..b79f277 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -30,6 +30,11 @@ dependencies = [
 ]
 dynamic = ["version"]
 
+[project.optional-dependencies]
+tests = [
+    "pytest",
+]
+
 [tool.setuptools]
 packages = ["markdown_include"]
 
diff --git a/unittests/resources/header.md b/tests/resources/header.md
similarity index 100%
rename from unittests/resources/header.md
rename to tests/resources/header.md
diff --git a/unittests/resources/simple.md b/tests/resources/simple.md
similarity index 100%
rename from unittests/resources/simple.md
rename to tests/resources/simple.md
diff --git a/unittests/resources/simple_2.md b/tests/resources/simple_2.md
similarity index 100%
rename from unittests/resources/simple_2.md
rename to tests/resources/simple_2.md
diff --git a/unittests/resources/template_inside.md b/tests/resources/template_inside.md
similarity index 100%
rename from unittests/resources/template_inside.md
rename to tests/resources/template_inside.md
diff --git a/tests/test_include.py b/tests/test_include.py
new file mode 100644
index 0000000..d9ba59e
--- /dev/null
+++ b/tests/test_include.py
@@ -0,0 +1,144 @@
+from markdown_include.include import IncludePreprocessor, MarkdownInclude
+
+import markdown
+import pathlib
+from textwrap import dedent
+
+import pytest
+
+
+RESOURCE_DIR = pathlib.Path(__file__).parent.absolute()
+
+
+@pytest.fixture(scope="module")
+def markdown_include():
+    return MarkdownInclude(configs={"base_path": RESOURCE_DIR})
+
+
+@pytest.fixture(scope="module")
+def markdown_include_inherit_heading_depth():
+    return MarkdownInclude(
+        configs={"base_path": RESOURCE_DIR, "inheritHeadingDepth": True}
+    )
+
+
+def test_single_include(markdown_include):
+    source = "{!resources/simple.md!}"
+    html = markdown.markdown(source, extensions=[markdown_include])
+
+    assert html == "<p>This is a simple template</p>"
+
+
+def test_double_include(markdown_include):
+    source = "{!resources/simple.md!} and {!resources/simple_2.md!}"
+    html = markdown.markdown(source, extensions=[markdown_include])
+
+    assert (
+        html == "<p>This is a simple template and This is another simple template</p>"
+    )
+
+
+def test_headers(markdown_include):
+    source = (
+        "Source file\n"
+        "# Heading Level 1 of main file\n"
+        "{!resources/header.md!}\n"
+        "## Heading Level 2 of main file\n"
+        "{!resources/header.md!}"
+    )
+
+    html = markdown.markdown(source, extensions=[markdown_include])
+
+    assert html == dedent(
+        """\
+        <p>Source file</p>
+        <h1>Heading Level 1 of main file</h1>
+        <h1>This heading will be one level deeper from the previous heading</h1>
+        <p>More included file content.
+        End of included content.</p>
+        <h2>Heading Level 2 of main file</h2>
+        <h1>This heading will be one level deeper from the previous heading</h1>
+        <p>More included file content.
+        End of included content.</p>"""
+    )
+
+
+def test_embedded_template(markdown_include):
+    source = "{!resources/template_inside.md!}"
+    html = markdown.markdown(source, extensions=[markdown_include])
+
+    assert (
+        html
+        == "<p>This is a simple template</p>\n<p>This is a template with a template.</p>"
+    )
+
+
+def test_single_include_inherit_heading_depth(markdown_include_inherit_heading_depth):
+    source = "{!resources/simple.md!}"
+    html = markdown.markdown(
+        source, extensions=[markdown_include_inherit_heading_depth]
+    )
+
+    assert html == "<p>This is a simple template</p>"
+
+
+def test_double_include_inherit_heading_depth(markdown_include_inherit_heading_depth):
+    source = "{!resources/simple.md!} and {!resources/simple_2.md!}"
+    html = markdown.markdown(
+        source, extensions=[markdown_include_inherit_heading_depth]
+    )
+
+    assert (
+        html == "<p>This is a simple template and This is another simple template</p>"
+    )
+
+
+def test_headers_inherit_heading_depth(markdown_include_inherit_heading_depth):
+    source = (
+        "Source file\n"
+        "# Heading Level 1 of main file\n"
+        "{!resources/header.md!}\n"
+        "## Heading Level 2 of main file\n"
+        "{!resources/header.md!}"
+    )
+
+    html = markdown.markdown(
+        source, extensions=[markdown_include_inherit_heading_depth]
+    )
+
+    assert html == dedent(
+        """\
+        <p>Source file</p>
+        <h1>Heading Level 1 of main file</h1>
+        <h2>This heading will be one level deeper from the previous heading</h2>
+        <p>More included file content.</p>
+        <p>End of included content.</p>
+        <h2>Heading Level 2 of main file</h2>
+        <h3>This heading will be one level deeper from the previous heading</h3>
+        <p>More included file content.</p>
+        <p>End of included content.</p>"""
+    )
+
+
+def test_processor_lines():
+    processor = IncludePreprocessor(
+        None,
+        {
+            "base_path": RESOURCE_DIR,
+            "encoding": "utf-8",
+            "inheritHeadingDepth": False,
+            "headingOffset": 0,
+            "throwException": False,
+        },
+    )
+
+    source = [
+        "Source file",
+        "# Heading Level 1 of main file",
+        "{!resources/header.md!}",
+        "## Heading Level 2 of main file",
+        "{!resources/header.md!}",
+    ]
+    result_lines = processor.run(source)
+
+    assert len(result_lines) == 9
diff --git a/unittests/test_embedded.py b/unittests/test_embedded.py
deleted file mode 100644
index a5e7d94..0000000
--- a/unittests/test_embedded.py
+++ /dev/null
@@ -1,20 +0,0 @@
-import os
-from unittest import TestCase
-
-import markdown
-
-from markdown_include.include import IncludePreprocessor, MarkdownInclude
-
-
-class TestEmbedded(TestCase):
-    def setUp(self) -> None:
-        self.maxDiff = None
-        self.markdown_include = MarkdownInclude(
-            configs={'base_path': os.path.dirname(os.path.realpath(__file__))}
-        )
-
-    def test_embedded_template(self):
-        source = "{!resources/template_inside.md!}"
-        html = markdown.markdown(source, extensions=[self.markdown_include])
-
-        self.assertEqual(html, "<p>This is a simple template</p>\n<p>This is a template with a template.</p>")
diff --git a/unittests/test_include.py b/unittests/test_include.py
deleted file mode 100644
index 62bb6c7..0000000
--- a/unittests/test_include.py
+++ /dev/null
@@ -1,45 +0,0 @@
-import os
-from unittest import TestCase
-
-import markdown
-
-from markdown_include.include import MarkdownInclude
-
-
-class TestInclude(TestCase):
-    def setUp(self) -> None:
-        self.maxDiff = None
-        self.markdown_include = MarkdownInclude(
-            configs={'base_path': os.path.dirname(os.path.realpath(__file__))}
-        )
-
-    def test_single_include(self):
-        source = "{!resources/simple.md!}"
-        html = markdown.markdown(source, extensions=[self.markdown_include])
-
-        self.assertEqual(html, '<p>This is a simple template</p>')
-
-    def test_double_include(self):
-        source = "{!resources/simple.md!} and {!resources/simple_2.md!}"
-        html = markdown.markdown(source, extensions=[self.markdown_include])
-
-        self.assertEqual(html, '<p>This is a simple template and This is another simple template</p>')
-
-    def test_headers(self):
-        source = "Source file\n" \
-                 "# Heading Level 1 of main file\n" \
-                 "{!resources/header.md!}\n" \
-                 "## Heading Level 2 of main file\n" \
-                 "{!resources/header.md!}"
-
-        html = markdown.markdown(source, extensions=[self.markdown_include])
-
-        self.assertEqual(html, "<p>Source file</p>\n"
-                                "<h1>Heading Level 1 of main file</h1>\n"
-                                "<h1>This heading will be one level deeper from the previous heading</h1>\n"
-                                "<p>More included file content.\n"
-                                "End of included content.</p>\n"
-                                "<h2>Heading Level 2 of main file</h2>\n"
-                                "<h1>This heading will be one level deeper from the previous heading</h1>\n"
-                                "<p>More included file content.\n"
-                                "End of included content.</p>")
diff --git a/unittests/test_include_header_indent.py b/unittests/test_include_header_indent.py
deleted file mode 100644
index 35f651d..0000000
--- a/unittests/test_include_header_indent.py
+++ /dev/null
@@ -1,45 +0,0 @@
-import os
-from unittest import TestCase
-
-import markdown
-
-from markdown_include.include import MarkdownInclude
-
-
-class TestInclude(TestCase):
-    def setUp(self) -> None:
-        self.maxDiff = None
-        self.markdown_include = MarkdownInclude(
-            configs={'base_path': os.path.dirname(os.path.realpath(__file__)), 'inheritHeadingDepth': True}
-        )
-
-    def test_single_include(self):
-        source = "{!resources/simple.md!}"
-        html = markdown.markdown(source, extensions=[self.markdown_include])
-
-        self.assertEqual(html, '<p>This is a simple template</p>')
-
-    def test_double_include(self):
-        source = "{!resources/simple.md!} and {!resources/simple_2.md!}"
-        html = markdown.markdown(source, extensions=[self.markdown_include])
-
-        self.assertEqual(html, '<p>This is a simple template and This is another simple template</p>')
-
-    def test_headers(self):
-        source = "Source file\n" \
-                 "# Heading Level 1 of main file\n" \
-                 "{!resources/header.md!}\n" \
-                 "## Heading Level 2 of main file\n" \
-                 "{!resources/header.md!}"
-
-        html = markdown.markdown(source, extensions=[self.markdown_include])
-
-        self.assertEqual(html, "<p>Source file</p>\n"
-                                "<h1>Heading Level 1 of main file</h1>\n"
-                                "<h2>This heading will be one level deeper from the previous heading</h2>\n"
-                                "<p>More included file content.</p>\n"
-                                "<p>End of included content.</p>\n"
-                                "<h2>Heading Level 2 of main file</h2>\n"
-                                "<h3>This heading will be one level deeper from the previous heading</h3>\n"
-                                "<p>More included file content.</p>\n"
-                                "<p>End of included content.</p>")
diff --git a/unittests/test_lines.py b/unittests/test_lines.py
deleted file mode 100644
index a97f1fe..0000000
--- a/unittests/test_lines.py
+++ /dev/null
@@ -1,26 +0,0 @@
-import os
-from unittest import TestCase
-
-from markdown_include.include import IncludePreprocessor
-
-
-class TestProcessor(TestCase):
-    def setUp(self) -> None:
-        self.maxDiff = None
-        self.processor = IncludePreprocessor(None, {
-            "base_path": os.path.dirname(os.path.realpath(__file__)),
-            "encoding": "utf-8",
-            "inheritHeadingDepth": False,
-            "headingOffset": 0,
-            "throwException": False,
-        })
-
-    def test_lines(self):
-        source = ["Source file",
-                  "# Heading Level 1 of main file",
-                  "{!resources/header.md!}",
-                  "## Heading Level 2 of main file",
-                  "{!resources/header.md!}"]
-        result_lines = self.processor.run(source)
-
-        self.assertEqual(9, len(result_lines))