diff --git a/.github/workflows/push.yml b/.github/workflows/push.yml
index fe65cb05..349894fb 100644
--- a/.github/workflows/push.yml
+++ b/.github/workflows/push.yml
@@ -18,25 +18,20 @@ jobs:
 
     steps:
     - uses: actions/checkout@v4
-    - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v5
-      with:
-        python-version: ${{ matrix.python-version }}
-    # Confirm that the `python` maps to the version we just installed.
-    # PowerShell on Windows does this differently than the Unix shells.
-    - run: which python ; python --version ; which pip ; pip --version
-      if: matrix.os != 'windows-latest'
-    - run: get-command python ; python --version ; get-command pip ; pip --version
-      if: matrix.os == 'windows-latest'
+    - uses: astral-sh/setup-uv@v5
     - run: git --version
-    # Make sure Subversion and Mercurial are installed on Windows and macOS.
-    - run: sudo apt-get update && sudo apt-get install -y subversion mercurial
+    # Make sure Subversion (including `svnadmin`) and Mercurial are installed
+    # on Windows and macOS. I'd prefer `uv tool install mercurial`, but the
+    # `hg` binary that that installs crashes on Windows for some reason. We
+    # don't need Mercurial to use the same Python version that we're using.
+    # Also Choco and WinGet seem to fail to put `hg` in the PATH for some
+    # reason.
+    - run: pip install mercurial
+    - run: sudo apt-get update && sudo apt-get install -y subversion
       if: matrix.os == 'ubuntu-latest'
-    - run: brew install subversion mercurial
+    - run: brew install subversion
       if: matrix.os == 'macOS-latest'
-    - run: choco install -y --no-progress sliksvn && pip install mercurial
+    - run: choco install -y --no-progress sliksvn
       if: matrix.os == 'windows-latest'
-    # Install test dependencies, like flake8.
-    - run: pip install -r ./requirements-dev.txt
     # Run tests.
-    - run: python test.py -v
+    - run: uv run --python ${{ matrix.python-version }} test.py -v
diff --git a/.gitignore b/.gitignore
index fe7dd1f7..15da050b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,3 +4,4 @@ __pycache__
 peru.egg-info
 build/
 dist/
+uv.lock
diff --git a/peru.py b/peru.py
index ce9d36a8..acaddd6c 100755
--- a/peru.py
+++ b/peru.py
@@ -3,6 +3,8 @@
 # This script is for running peru directly from the repo, mainly for
 # development. This isn't what gets installed when you install peru. That would
 # be a script generated by setup.py, which calls peru.main.main().
+#
+# Update October 2025: `uv run peru` also works.
 
 import os
 import sys
diff --git a/pyproject.toml b/pyproject.toml
new file mode 100644
index 00000000..b3bbbcac
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,40 @@
+[project]
+name = "peru"
+dynamic = ["version"]
+description = "A tool for fetching code"
+readme = "README.md"
+license = "MIT"
+authors = [
+    { name = "Jack O'Connor", email = "oconnor663@gmail.com" },
+    { name = "Sean Olson", email = "olson.sean.k@gmail.com" },
+]
+requires-python = ">=3.8"
+dependencies = [
+    "PyYAML",
+]
+
+[project.urls]
+Repository = "https://github.com/buildinspace/peru"
+
+[project.scripts]
+peru = "peru.main:main"
+
+[build-system]
+requires = ["hatchling"]
+build-backend = "hatchling.build"
+
+[tool.hatch.build]
+include = [
+    "peru/**/*.py",
+    "peru/VERSION",
+    "peru/resources/**/*",
+]
+
+[tool.hatch.version]
+path = "peru/VERSION"
+pattern = "(?P<version>.+)"
+
+[dependency-groups]
+dev = [
+    "flake8",
+]
diff --git a/requirements-dev.txt b/requirements-dev.txt
deleted file mode 100644
index 9c4d6cd6..00000000
--- a/requirements-dev.txt
+++ /dev/null
@@ -1,4 +0,0 @@
-coverage
-flake8
-
--e .
diff --git a/setup.py b/setup.py
deleted file mode 100644
index 582f883c..00000000
--- a/setup.py
+++ /dev/null
@@ -1,59 +0,0 @@
-import os
-import setuptools
-import sys
-
-# Written according to the docs at
-# https://packaging.python.org/en/latest/distributing.html
-
-project_root = os.path.dirname(__file__)
-readme_file = os.path.join(project_root, 'README.md')
-module_root = os.path.join(project_root, 'peru')
-version_file = os.path.join(module_root, 'VERSION')
-
-
-def get_version():
-    with open(version_file) as f:
-        return f.read().strip()
-
-
-def get_all_resources_filepaths():
-    resources_paths = ['VERSION']
-    resources_dir = os.path.join(module_root, 'resources')
-    for dirpath, dirnames, filenames in os.walk(resources_dir):
-        relpaths = [
-            os.path.relpath(os.path.join(dirpath, f), start=module_root)
-            for f in filenames
-        ]
-        resources_paths.extend(relpaths)
-    return resources_paths
-
-
-def get_install_requires():
-    dependencies = ['PyYAML']
-    if sys.version_info < (3, 5):
-        raise RuntimeError('The minimum supported Python version is 3.5.')
-    return dependencies
-
-
-def readme_text():
-    with open(readme_file) as f:
-        return f.read().strip()
-
-
-setuptools.setup(
-    name='peru',
-    description='A tool for fetching code',
-    version=get_version(),
-    url='https://github.com/buildinspace/peru',
-    author="Jack O'Connor <oconnor663@gmail.com>, "
-    "Sean Olson <olson.sean.k@gmail.com>",
-    license='MIT',
-    packages=['peru', 'peru.docopt'],
-    package_data={'peru': get_all_resources_filepaths()},
-    entry_points={'console_scripts': [
-        'peru=peru.main:main',
-    ]},
-    install_requires=get_install_requires(),
-    long_description=readme_text(),
-    long_description_content_type='text/markdown',
-)