diff --git a/.github/renovate.json b/.github/renovate.json
deleted file mode 100644
index 4f39080..0000000
--- a/.github/renovate.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "extends": ["config:base"]
-}
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
new file mode 100644
index 0000000..3f1c0bb
--- /dev/null
+++ b/.github/workflows/release.yml
@@ -0,0 +1,16 @@
+name: Release
+
+on:
+  release:
+    types: [released]
+
+jobs:
+  publish-to-pypi:
+    runs-on: ubuntu-latest
+    permissions:
+      id-token: write
+    steps:
+      - uses: actions/checkout@v6
+      - uses: astral-sh/setup-uv@v7
+      - run: uv build --wheel
+      - uses: pypa/gh-action-pypi-publish@release/v1
diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 3a17b76..b380f8b 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -12,32 +12,26 @@ jobs:
   lint:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
-      - uses: pre-commit/action@v3.0.0
+      - uses: actions/checkout@v6
+      - uses: j178/prek-action@v2
 
   build:
     needs: [lint]
 
     strategy:
       matrix:
-        platform: [ubuntu-latest]
-        python-version: ["3.7", "3.11"]
-        include:
-          - platform: macos-latest
-            python-version: "3.11"
-          - platform: windows-latest
-            python-version: "3.11"
+        platform: [ubuntu-latest, macos-latest, windows-latest]
+        python-version: ["3.10", "3.15"]
 
     runs-on: ${{ matrix.platform }}
 
     steps:
-      - uses: actions/setup-python@v4
+      - uses: actions/checkout@v6
+
+      - uses: astral-sh/setup-uv@v7
         with:
           python-version: ${{ matrix.python-version }}
-      - uses: actions/checkout@v4
-      - name: Test with tox
+
+      - name: Test
         run: |
-          pip install tox
-          tox -- --cov pytest_codeblocks --cov-report xml --cov-report term
-      - uses: codecov/codecov-action@v4-beta
-        if: ${{ matrix.python-version == '3.11' && matrix.os == 'ubuntu-latest' }}
+          uv run pytest
diff --git a/.gitignore b/.gitignore
index f76b87b..bd66d07 100644
--- a/.gitignore
+++ b/.gitignore
@@ -7,3 +7,4 @@ dist/
 *.png
 .pytest_cache/
 .tox/
+uv.lock
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index d22aab6..b5ad1c1 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -1,16 +1,11 @@
 repos:
-  - repo: https://github.com/charliermarsh/ruff-pre-commit
-    rev: v0.0.290
+  - repo: https://github.com/astral-sh/ruff-pre-commit
+    rev: v0.15.17
     hooks:
-      - id: ruff
-
-  - repo: https://github.com/psf/black
-    rev: 23.9.1
-    hooks:
-      - id: black
-        language_version: python3
+      - id: ruff-check
+      - id: ruff-format
 
   - repo: https://github.com/pre-commit/mirrors-prettier
-    rev: v3.0.3
+    rev: v3.1.0
     hooks:
       - id: prettier
diff --git a/justfile b/justfile
index 698f532..c60e73b 100644
--- a/justfile
+++ b/justfile
@@ -1,21 +1,25 @@
-version := `python3 -c "from src.pytest_codeblocks.__about__ import __version__; print(__version__)"`
+version := `python -c "import tomllib; print(tomllib.load(open('pyproject.toml', 'rb'))['project']['version'])"`
 
 default:
 	@echo "\"just publish\"?"
 
-publish:
+publish: release
+
+release:
 	@if [ "$(git rev-parse --abbrev-ref HEAD)" != "main" ]; then exit 1; fi
-	gh release create "v{{version}}"
-	flit publish
+	gh release create {{version}}
 
 clean:
 	@find . | grep -E "(__pycache__|\.pyc|\.pyo$)" | xargs rm -rf
 	@rm -rf src/*.egg-info/ build/ dist/ .tox/
 
 format:
-	ruff src/ tests/ --fix
-	black src/ tests/
+	ruff format .
+	ruff check --fix .
 	blacken-docs README.md
 
 lint:
-	pre-commit run --all
+	prek run --all-files
+
+test:
+  uv run pytest
diff --git a/pyproject.toml b/pyproject.toml
index a728d17..b5fdd19 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,38 +4,27 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "pytest_codeblocks"
-authors = [{name = "Nico Schlömer", email = "nico.schloemer@gmail.com"}]
+version = "0.18.0"
+authors = [{ name = "Nico Schlömer", email = "nico.schloemer@gmail.com" }]
 description = "Test code blocks in your READMEs"
 readme = "README.md"
-license = {file = "LICENSE.txt"}
+license = { file = "LICENSE.txt" }
 classifiers = [
   "Development Status :: 5 - Production/Stable",
   "Framework :: Pytest",
   "Intended Audience :: Developers",
   "License :: OSI Approved :: MIT License",
   "Operating System :: OS Independent",
-  "Programming Language :: Python",
   "Programming Language :: Python :: 3",
-  "Programming Language :: Python :: 3.7",
-  "Programming Language :: Python :: 3.8",
-  "Programming Language :: Python :: 3.9",
-  "Programming Language :: Python :: 3.10",
-  "Programming Language :: Python :: 3.11",
-  "Programming Language :: Python :: 3.12",
-]
-dynamic = ["version"]
-requires-python = ">=3.7"
-dependencies = [
-   "pytest >= 7.0.0"
 ]
+requires-python = ">=3.10"
+dependencies = ["pytest >= 7.0.0"]
 
-[tool.setuptools.dynamic]
-version = {attr = "pytest_codeblocks.__about__.__version__"}
+[dependency-groups]
+dev = ["pytest"]
 
 [project.urls]
 Homepage = "https://github.com/nschloe/pytest-codeblocks"
-Code = "https://github.com/nschloe/pytest-codeblocks"
-Issues = "https://github.com/nschloe/pytest-codeblocks/issues"
 Funding = "https://github.com/sponsors/nschloe"
 
 [project.entry-points.pytest11]
diff --git a/src/pytest_codeblocks/__about__.py b/src/pytest_codeblocks/__about__.py
deleted file mode 100644
index fd86b3e..0000000
--- a/src/pytest_codeblocks/__about__.py
+++ /dev/null
@@ -1 +0,0 @@
-__version__ = "0.17.0"
diff --git a/src/pytest_codeblocks/__init__.py b/src/pytest_codeblocks/__init__.py
index b0813f1..cfe1c24 100644
--- a/src/pytest_codeblocks/__init__.py
+++ b/src/pytest_codeblocks/__init__.py
@@ -1,5 +1,4 @@
 from . import plugin
-from .__about__ import __version__
 from .main import CodeBlock, extract_from_buffer, extract_from_file
 
 __all__ = [
@@ -7,5 +6,4 @@
     "extract_from_buffer",
     "extract_from_file",
     "plugin",
-    "__version__",
 ]
diff --git a/src/pytest_codeblocks/main.py b/src/pytest_codeblocks/main.py
index 36060c2..3612f89 100644
--- a/src/pytest_codeblocks/main.py
+++ b/src/pytest_codeblocks/main.py
@@ -1,12 +1,8 @@
-from __future__ import annotations
-
 import contextlib
 import re
 import sys
 import warnings
 
-# namedtuple with default arguments
-# <https://stackoverflow.com/a/18348004/353337>
 from dataclasses import dataclass, field
 from io import StringIO
 from pathlib import Path
@@ -20,7 +16,7 @@ class CodeBlock:
     expected_output: str | None = None
     expected_output_ignore_whitespace: bool = False
     importorskip: str | None = None
-    marks: list[str] = field(default_factory=lambda: [])
+    marks: list[str] = field(default_factory=list)
 
 
 def extract_from_file(
@@ -73,7 +69,6 @@ def extract_from_buffer(f, max_num_lines: int = 10000) -> list[CodeBlock]:
                     )
                 expected_output_block = out[-1]
                 if keyword == "expected-output-ignore-whitespace":
-                    # \s: regex matches all whitespace characters
                     expected_output_ignore_whitespace = True
 
             elif keyword == "cont":
@@ -171,6 +166,7 @@ def extract_from_buffer(f, max_num_lines: int = 10000) -> list[CodeBlock]:
                     expected_output_ignore_whitespace
                 )
                 expected_output_block = None
+                expected_output_ignore_whitespace = False
 
             else:
                 out.append(
@@ -195,5 +191,7 @@ def stdout_io(stdout=None):
     if stdout is None:
         stdout = StringIO()
     sys.stdout = stdout
-    yield stdout
-    sys.stdout = old
+    try:
+        yield stdout
+    finally:
+        sys.stdout = old
diff --git a/src/pytest_codeblocks/plugin.py b/src/pytest_codeblocks/plugin.py
index d0e931e..ce6ce60 100644
--- a/src/pytest_codeblocks/plugin.py
+++ b/src/pytest_codeblocks/plugin.py
@@ -1,10 +1,6 @@
-#
-# Take a look at the example
-# https://docs.pytest.org/en/stable/example/nonpython.html
-#
 import subprocess
-from pathlib import Path
 import re
+import sys
 
 import pytest
 
@@ -20,17 +16,13 @@ def pytest_addoption(parser):
     )
 
 
-def pytest_collect_file(path, parent):
+def pytest_collect_file(file_path, parent):
     config = parent.config
-    path = Path(path)
-    if config.option.codeblocks and path.suffix == ".md":
-        return MarkdownFile.from_parent(parent, path=path)
+    if config.option.codeblocks and file_path.suffix == ".md":
+        return MarkdownFile.from_parent(parent, path=file_path)
 
 
 class MarkdownFile(pytest.File):
-    def __init__(self, **kwargs):
-        super().__init__(**kwargs)
-
     def collect(self):
         for block in extract_from_file(self.path):
             if block.syntax not in ["python", "sh", "bash"]:
@@ -44,14 +36,7 @@ def collect(self):
             out.obj = block
 
             for mark in block.marks:
-                # A common thing is
-                #
-                # pytest.mark.skipif(sys.version_info < (3, 10), reason="...")
-                #
-                # which needs sys. Import it here.
-                import sys  # noqa: F401
-
-                out.add_marker(eval(mark))
+                out.add_marker(eval(mark, {"sys": sys, "pytest": pytest}))
 
             yield out
 
@@ -62,13 +47,12 @@ def __init__(self, name, parent, obj=None):
         self.obj = obj
 
     def runtest(self):
-        assert self.obj is not None
         output = None
 
         if self.obj.importorskip is not None:
             try:
                 __import__(self.obj.importorskip)
-            except (ImportError, ModuleNotFoundError):
+            except ImportError:
                 pytest.skip()
 
         if self.obj.syntax == "python":
@@ -85,20 +69,17 @@ def runtest(self):
                     )
             output = s.getvalue()
         else:
-            assert self.obj.syntax in ["sh", "bash"]
             executable = {
                 "sh": None,
                 "bash": "/bin/bash",
                 "zsh": "/bin/zsh",
             }[self.obj.syntax]
 
-            # TODO for python 3.7+, stdout=subprocess.PIPE can be replaced
-            #      by capture_output=True
             ret = subprocess.run(
                 self.obj.code,
                 shell=True,
                 check=True,
-                stdout=subprocess.PIPE,
+                capture_output=True,
                 executable=executable,
             )
             output = ret.stdout.decode()
@@ -119,12 +100,7 @@ def runtest(self):
                 )
 
     def repr_failure(self, excinfo):
-        """Called when self.runtest() raises an exception."""
-        # if isinstance(excinfo.value, CodeblockException):
         return excinfo.value.args[0]
-        # if excinfo.errisinstance(RuntimeError):
-        #     return excinfo.value.args[0].stdout
-        # return super().repr_failure(excinfo)
 
     def reportinfo(self):
         return (self.path, -1, "code block check")
diff --git a/tests/conftest.py b/tests/conftest.py
new file mode 100644
index 0000000..c6481d5
--- /dev/null
+++ b/tests/conftest.py
@@ -0,0 +1 @@
+pytest_plugins = ["pytester"]
diff --git a/tests/test_comment_styles.py b/tests/test_comment_styles.py
index 907372d..25ecbb3 100644
--- a/tests/test_comment_styles.py
+++ b/tests/test_comment_styles.py
@@ -10,7 +10,7 @@
         "<!--- pytest-codeblocks:cont --->",
     ],
 )
-def test_cont(testdir, comment):
+def test_cont(pytester, comment):
     string = """
     Lorem ipsum
     ```python
@@ -22,6 +22,6 @@ def test_cont(testdir, comment):
     a + 1
     ```
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(passed=1)
diff --git a/tests/test_cont.py b/tests/test_cont.py
index 3744291..5a4ba71 100644
--- a/tests/test_cont.py
+++ b/tests/test_cont.py
@@ -1,4 +1,4 @@
-def test_cont(testdir):
+def test_cont(pytester):
     string = """
     Lorem ipsum
     ```python
@@ -10,12 +10,12 @@ def test_cont(testdir):
     a + 1
     ```
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(passed=1)
 
 
-def test_hidden_cont(testdir):
+def test_hidden_cont(pytester):
     string = """
     Lorem ipsum
     <!--
@@ -29,18 +29,18 @@ def test_hidden_cont(testdir):
     a + 1
     ```
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(passed=1)
 
 
-def test_nocont(testdir):
+def test_nocont(pytester):
     string = """
     <!--pytest-codeblocks:cont-->
     ```python
     1 + 2 + 3
     ```
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(errors=1)
diff --git a/tests/test_errors.py b/tests/test_errors.py
index a531668..28fed74 100644
--- a/tests/test_errors.py
+++ b/tests/test_errors.py
@@ -5,13 +5,13 @@
 import pytest_codeblocks
 
 
-def test_unclosed(testdir):
+def test_unclosed(pytester):
     string = """
     ```python
     1 + 2 + 3
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(errors=1)
 
 
diff --git a/tests/test_expect_error.py b/tests/test_expect_error.py
index c4dbf65..7f30d5c 100644
--- a/tests/test_expect_error.py
+++ b/tests/test_expect_error.py
@@ -1,40 +1,40 @@
-def test_expect_error(testdir):
+def test_expect_error(pytester):
     string = """
     <!--pytest.mark.xfail-->
     ```python
     raise RuntimeError()
     ```
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(xfailed=1)
 
 
-def test_expect_error_runtimeerror(testdir):
+def test_expect_error_runtimeerror(pytester):
     string = """
     <!--pytest.mark.xfail(raises=RuntimeError)-->
     ```python
     raise RuntimeError()
     ```
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(xfailed=1)
 
 
-def test_expect_error_indexerror(testdir):
+def test_expect_error_indexerror(pytester):
     string = """
     <!--pytest.mark.xfail(raises=IndexError)-->
     ```python
     raise RuntimeError()
     ```
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(failed=1)
 
 
-def test_expect_error_fail(testdir):
+def test_expect_error_fail(pytester):
     string1 = """
     Lorem ipsum
     <!--pytest.mark.xfail-->
@@ -42,6 +42,6 @@ def test_expect_error_fail(testdir):
     1 + 1
     ```
     """
-    testdir.makefile(".md", string1)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string1)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(xpassed=1)
diff --git a/tests/test_expected_output.py b/tests/test_expected_output.py
index 55c0f46..7ae3cd4 100644
--- a/tests/test_expected_output.py
+++ b/tests/test_expected_output.py
@@ -1,4 +1,4 @@
-def test_expected_output(testdir):
+def test_expected_output(pytester):
     string = """
     Lorem ipsum
     ```python
@@ -14,12 +14,12 @@ def test_expected_output(testdir):
     3
     ```
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(passed=1)
 
 
-def test_expected_output_fail(testdir):
+def test_expected_output_fail(pytester):
     string = """
     Lorem ipsum
     ```python
@@ -31,12 +31,12 @@ def test_expected_output_fail(testdir):
     5
     ```
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(failed=1)
 
 
-def test_expected_output_ignore_whitespace(testdir):
+def test_expected_output_ignore_whitespace(pytester):
     string = """
 Lorem ipsum
 ```python
@@ -52,12 +52,12 @@ def test_expected_output_ignore_whitespace(testdir):
   3
 ```
 """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(passed=1)
 
 
-def test_expected_output_ignore_whitespace_fail(testdir):
+def test_expected_output_ignore_whitespace_fail(pytester):
     string = """
 Lorem ipsum
 ```python
@@ -73,6 +73,6 @@ def test_expected_output_ignore_whitespace_fail(testdir):
   5
 ```
 """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(failed=1)
diff --git a/tests/test_general.py b/tests/test_general.py
index 9227bb7..21b5326 100644
--- a/tests/test_general.py
+++ b/tests/test_general.py
@@ -3,7 +3,7 @@
 import pytest_codeblocks
 
 
-def test_basic(testdir):
+def test_basic(pytester):
     string1 = """
     Lorem ipsum
     ```python
@@ -11,12 +11,12 @@ def test_basic(testdir):
     ```
     dolor sit amet
     """
-    testdir.makefile(".md", string1)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string1)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(passed=1)
 
 
-def test_skip(testdir):
+def test_skip(pytester):
     string1 = """
     Lorem ipsum
     <!--pytest.mark.skip-->
@@ -33,8 +33,8 @@ def test_skip(testdir):
     1 + 2 + 3
     ```
     """
-    testdir.makefile(".md", string1)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string1)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(skipped=2)
 
 
diff --git a/tests/test_shell.py b/tests/test_shell.py
index f53607d..3073595 100644
--- a/tests/test_shell.py
+++ b/tests/test_shell.py
@@ -6,7 +6,7 @@
     pytest.skip("skipping shell tests", allow_module_level=True)
 
 
-def test_shell(testdir):
+def test_shell(pytester):
     string = """
     Lorem ipsum
     ```sh
@@ -17,47 +17,47 @@ def test_shell(testdir):
     cd
     ```
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(passed=2)
 
 
-def test_shell_fail(testdir):
+def test_shell_fail(pytester):
     string = """
     ```sh
     cdc
     ```
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(failed=1)
 
 
-def test_shell_expect_fail(testdir):
+def test_shell_expect_fail(pytester):
     string = """
     <!--pytest.mark.xfail-->
     ```sh
     cdc
     ```
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(xfailed=1)
 
 
-def test_shell_expect_fail_passed(testdir):
+def test_shell_expect_fail_passed(pytester):
     string = """
     <!--pytest.mark.xfail-->
     ```sh
     cd
     ```
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(xpassed=1)
 
 
-def test_shell_expect_output(testdir):
+def test_shell_expect_output(pytester):
     string = """
     ```sh
     echo abc
@@ -67,12 +67,12 @@ def test_shell_expect_output(testdir):
     abc
     ```
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(passed=1)
 
 
-def test_shell_expect_output_fail(testdir):
+def test_shell_expect_output_fail(pytester):
     string = """
     ```sh
     echo abc
@@ -82,12 +82,12 @@ def test_shell_expect_output_fail(testdir):
     ac
     ```
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(failed=1)
 
 
-def test_bash(testdir):
+def test_bash(pytester):
     string = """
     ```bash
     foo=1
@@ -100,6 +100,6 @@ def test_bash(testdir):
     abc
     ```
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(passed=1)
diff --git a/tests/test_skipif.py b/tests/test_skipif.py
index 8348157..fc0d72d 100644
--- a/tests/test_skipif.py
+++ b/tests/test_skipif.py
@@ -1,4 +1,4 @@
-def test_skip(testdir):
+def test_skip(pytester):
     string = """
     Lorem ipsum
 
@@ -8,12 +8,12 @@ def test_skip(testdir):
     print(1 + 3)
     ```
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(skipped=1)
 
 
-def test_skip_expected_output(testdir):
+def test_skip_expected_output(pytester):
     string = """
     Lorem ipsum
 
@@ -30,12 +30,12 @@ def test_skip_expected_output(testdir):
     ```
 
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(skipped=1)
 
 
-def test_skipif(testdir):
+def test_skipif(pytester):
     string = """
     Lorem ipsum
 
@@ -45,12 +45,12 @@ def test_skipif(testdir):
     print(1 + 3)
     ```
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(skipped=1)
 
 
-def test_skipif2(testdir):
+def test_skipif2(pytester):
     string = """
     Lorem ipsum
 
@@ -60,12 +60,12 @@ def test_skipif2(testdir):
     print(1 + 3)
     ```
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(passed=1)
 
 
-def test_skipif_expected_output(testdir):
+def test_skipif_expected_output(pytester):
     string = """
     Lorem ipsum
 
@@ -82,12 +82,12 @@ def test_skipif_expected_output(testdir):
     ```
 
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(skipped=1)
 
 
-def test_skipif_expected_output2(testdir):
+def test_skipif_expected_output2(pytester):
     string = """
     Lorem ipsum
 
@@ -104,12 +104,12 @@ def test_skipif_expected_output2(testdir):
     ```
 
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(passed=1)
 
 
-def test_importorskip(testdir):
+def test_importorskip(pytester):
     string = """
     Lorem ipsum
 
@@ -119,12 +119,12 @@ def test_importorskip(testdir):
     print(1 + 3)
     ```
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(skipped=1)
 
 
-def test_importorskip2(testdir):
+def test_importorskip2(pytester):
     string = """
     Lorem ipsum
 
@@ -134,6 +134,6 @@ def test_importorskip2(testdir):
     print(1 + 3)
     ```
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(passed=1)
diff --git a/tests/test_unicode.py b/tests/test_unicode.py
index f0937ad..ec273dd 100644
--- a/tests/test_unicode.py
+++ b/tests/test_unicode.py
@@ -1,4 +1,4 @@
-def test_unicode(testdir):
+def test_unicode(pytester):
     # Unicode identifyers are in fact legal Python code
     string = """
     ```python
@@ -7,6 +7,6 @@ def test_unicode(testdir):
     α = 1
     ```
     """
-    testdir.makefile(".md", string)
-    result = testdir.runpytest("--codeblocks")
+    pytester.makefile(".md", string)
+    result = pytester.runpytest("--codeblocks")
     result.assert_outcomes(passed=1)
diff --git a/tox.ini b/tox.ini
deleted file mode 100644
index 17a0bd9..0000000
--- a/tox.ini
+++ /dev/null
@@ -1,10 +0,0 @@
-[tox]
-envlist = py3
-isolated_build = True
-
-[testenv]
-deps =
-    pytest
-    pytest-cov
-commands =
-    pytest {posargs} -p pytester