diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index eff0b74..dd9c4d5 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -9,7 +9,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python: ['3.7', '3.8', '3.9', '3.10']
+        python: ['3.8', '3.9', '3.10', '3.11', '3.12']
 
     steps:
       - name: Checkout
@@ -34,7 +34,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python: ['3.7', '3.8', '3.9', '3.10', '3.11-dev']
+        python: ['3.8', '3.9', '3.10', '3.11', '3.12']
         check_formatting: ['0']
         extra_name: ['']
         include:
@@ -70,7 +70,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python: ['3.7', '3.8', '3.9', '3.10']
+        python: ['3.8', '3.9', '3.10', '3.11', '3.12']
     steps:
       - name: Checkout
         uses: actions/checkout@v4
diff --git a/ci.sh b/ci.sh
index 85d2a18..dee5ca2 100755
--- a/ci.sh
+++ b/ci.sh
@@ -1,21 +1,42 @@
 #!/bin/bash
 
-set -ex
+set -ex -o pipefail
 
-CHECK_FILES="setup.py src tests"
+CHECK_FILES="src tests"
 YAPF_VERSION=0.20.1
 
-python -m pip install -U pip setuptools wheel
+# Log some general info about the environment
+echo "::group::Environment"
+uname -a
+env | sort
+echo "::endgroup::"
 
-python setup.py sdist --formats=zip
-pip install dist/*.zip
+################################################################
+# We have a Python environment!
+################################################################
 
+echo "::group::Versions"
+python -c "import sys, struct; print('python:', sys.version); print('version_info:', sys.version_info); print('bits:', struct.calcsize('P') * 8)"
+echo "::endgroup::"
+
+echo "::group::Install dependencies"
+python -m pip install -U pip build
+python -m pip --version
+
+python -m build
+python -m pip install dist/*.whl
+echo "::endgroup::"
+
+echo "::group::Setup for tests"
 # Install dependencies.
 pip install -Ur test-requirements.txt
+echo "::endgroup::"
 
 if [ "$CHECK_FORMATTING" = "1" ]; then
+    echo "::group::Yapf"
     pip install yapf==${YAPF_VERSION} "isort>=5" mypy pyright
     if ! yapf -rpd $CHECK_FILES; then
+        echo "::endgroup::"
         cat <<EOF
 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
@@ -30,10 +51,15 @@ in your local checkout.
 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 EOF
+        echo "::error:: yapf found issues"
         exit 1
+    else
+        echo "::endgroup::"
     fi
 
+    echo "::group::isort"
     if ! isort --check-only --diff $CHECK_FILES ; then
+        echo "::endgroup::"
         cat <<EOF
 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
@@ -48,10 +74,15 @@ in your local checkout.
 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 EOF
+        echo "::error:: isort found issues"
         exit 1
+    else
+        echo "::endgroup::"
     fi
 
+    echo "::group::Mypy"
     if ! mypy src/ tests/type_tests.py ; then
+        echo "::endgroup::"
         cat <<EOF
 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
@@ -66,9 +97,13 @@ in your local checkout.
 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 EOF
+        echo "::error:: Mypy found issues"
         exit 1
+    else
+        echo "::endgroup::"
     fi
 
+    echo "::group::Pyright"
     if ! pyright --verifytypes outcome src/outcome/ ; then
         cat <<EOF
 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
@@ -84,12 +119,19 @@ in your local checkout.
 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 EOF
+        echo "::error:: Pyright found issues"
         exit 1
+    else
+        echo "::endgroup::"
     fi
 
     exit 0
 fi
 
+echo "::group:: Run Tests"
 pytest -W error -ra -v tests --cov --cov-config=.coveragerc
+echo "::endgroup::"
 
+echo "::group:: Code Coverage"
 bash <(curl -s https://codecov.io/bash)
+echo "::endgroup::"
\ No newline at end of file
diff --git a/pyproject.toml b/pyproject.toml
index 1cd2f25..845e958 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,18 +1,133 @@
+[build-system]
+requires = ["setuptools >= 64"]
+build-backend = "setuptools.build_meta"
+
+[project]
+name="outcome"
+description="Capture the outcome of Python function calls."
+authors = [{name = "Frazer McLean", email = "frazer@frazermclean.co.uk"}]
+license = {text = "MIT OR Apache-2.0"}
+keywords = [
+    "result",
+]
+classifiers=[
+    "Development Status :: 5 - Production/Stable",
+    "Framework :: Trio",
+    "Intended Audience :: Developers",
+    "License :: OSI Approved :: MIT License",
+    "License :: OSI Approved :: Apache Software License",
+    "Operating System :: POSIX :: Linux",
+    "Operating System :: MacOS :: MacOS X",
+    "Operating System :: Microsoft :: Windows",
+    "Programming Language :: Python :: Implementation :: CPython",
+    "Programming Language :: Python :: Implementation :: PyPy",
+    "Programming Language :: Python :: 3 :: Only",
+    "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",
+    "Typing :: Typed",
+]
+requires-python = ">=3.8"
+dependencies = [
+    # attrs 19.2.0 adds `eq` option to decorators
+    "attrs>=19.2.0"
+]
+dynamic = ["version"]
+
+[project.readme]
+file = "README.rst"
+content-type = "text/x-rst"
+
+[project.urls]
+Homepage = "https://github.com/python-trio/outcome"
+Documentation = "https://outcome.readthedocs.io/en/latest/"
+Changelog = "https://outcome.readthedocs.io/en/latest/history.html"
+Chat = "https://gitter.im/python-trio/general"
+
+[tool.setuptools]
+# This means, just install *everything* you see under outcome/, even if it
+# doesn't look like a source file, so long as it appears in MANIFEST.in:
+include-package-data = true
+
+[tool.setuptools.dynamic]
+version = {attr = "outcome._version.__version__"}
+
 [tool.towncrier]
-package = "outcome"
-filename = "docs/source/history.rst"
 directory = "newsfragments"
-underlines = ["-", "~", "^"]
+filename = "docs/source/history.rst"
 issue_format = "`#{issue} <https://github.com/python-trio/outcome/issues/{issue}>`__"
+# Usage:
+# - PRs should drop a file like "issuenumber.feature" in newsfragments
+# (or "bugfix", "doc", "removal", "misc"; misc gets no text, we can
+# customize this)
+# - At release time after bumping version number, run: towncrier
+# (or towncrier --draft)
+package = "outcome"
+package_dir = "src"
+underlines = ["-", "~", "^"]
+
+[[tool.towncrier.type]]
+directory = "feature"
+name = "Features"
+showcontent = true
+
+[[tool.towncrier.type]]
+directory = "bugfix"
+name = "Bugfixes"
+showcontent = true
+
+[[tool.towncrier.type]]
+directory = "doc"
+name = "Improved documentation"
+showcontent = true
+
+[[tool.towncrier.type]]
+directory = "removal"
+name = "Removals without deprecations"
+showcontent = true
+
+[[tool.towncrier.type]]
+directory = "misc"
+name = "Miscellaneous internal changes"
+showcontent = true
+
+[tool.coverage.run]
+branch = true
+source_pkgs = ["outcome", "tests"]
+omit = [
+    "tests/type_tests.py",
+]
+
+[tool.coverage.report]
+precision = 1
+exclude_lines = [
+    "pragma: no cover",
+    "abc.abstractmethod",
+    "if TYPE_CHECKING.*:",
+    "@overload",
+    "raise NotImplementedError",
+]
+partial_branches = [
+    "pragma: no branch",
+    "if not TYPE_CHECKING:",
+    "if .* or not TYPE_CHECKING:",
+]
 
 [tool.isort]
 combine_as_imports = true
 profile = "black"
 skip_gitignore = true
+skip = ["./build", "./docs"]
+known_first_party = ["outcome"]
 
 [tool.mypy]
+python_version = "3.8"
+
 # Be strict about use of Mypy
 strict = true
+local_partial_types = true
 warn_unused_ignores = true
 warn_unused_configs = true
 warn_redundant_casts = true
@@ -34,3 +149,6 @@ disallow_untyped_decorators = true
 
 # DO NOT use `ignore_errors`; it doesn't apply
 # downstream and users have to deal with them.
+
+[tool.pytest.ini_options]
+asyncio_mode = "strict"
diff --git a/setup.cfg b/setup.cfg
deleted file mode 100644
index 7e0298f..0000000
--- a/setup.cfg
+++ /dev/null
@@ -1,27 +0,0 @@
-[bdist_wheel]
-universal = 1
-
-[isort]
-multi_line_output = 4
-skip = ./build, ./docs
-# ci/travis.sh installs outcome normally, so isort assumes it's third party
-known_first_party = outcome
-
-[coverage:run]
-branch = True
-source =
-    outcome
-    tests/
-omit =
-    tests/type_tests.py
-
-[coverage:report]
-precision = 1
-exclude_lines =
-    pragma: no cover
-    abc.abstractmethod
-    if TYPE_CHECKING:
-    @overload
-
-[tool:pytest]
-asyncio_mode = strict
diff --git a/setup.py b/setup.py
deleted file mode 100644
index 008d005..0000000
--- a/setup.py
+++ /dev/null
@@ -1,50 +0,0 @@
-from setuptools import find_packages, setup
-
-version = dict()
-
-with open('src/outcome/_version.py') as fp:
-    version_mod = fp.read()
-
-exec(version_mod, version)
-
-LONG_DESC = open('README.rst').read()
-
-setup(
-    name='outcome',
-    version=version['__version__'],
-    description='Capture the outcome of Python function calls.',
-    url='https://github.com/python-trio/outcome',
-    project_urls={
-        "Documentation": "https://outcome.readthedocs.io/en/latest/",
-        "Chat": "https://gitter.im/python-trio/general",
-        "Changelog": "https://outcome.readthedocs.io/en/latest/history.html",
-    },
-    long_description=LONG_DESC,
-    long_description_content_type='text/x-rst',
-    author='Frazer McLean',
-    author_email='frazer@frazermclean.co.uk',
-    license='MIT OR Apache-2.0',
-    packages=find_packages('src'),
-    package_dir={'': 'src'},
-    include_package_data=True,
-    install_requires=['attrs>=19.2.0'],
-    python_requires='>=3.7',
-    keywords='result',
-    classifiers=[
-        'Development Status :: 5 - Production/Stable',
-        'Framework :: Trio',
-        'Intended Audience :: Developers',
-        'License :: OSI Approved :: MIT License',
-        'License :: OSI Approved :: Apache Software License',
-        'Operating System :: POSIX :: Linux',
-        'Operating System :: MacOS :: MacOS X',
-        'Operating System :: Microsoft :: Windows',
-        'Programming Language :: Python :: 3.7',
-        'Programming Language :: Python :: 3.8',
-        'Programming Language :: Python :: 3.9',
-        'Programming Language :: Python :: 3.10',
-        'Programming Language :: Python :: Implementation :: CPython',
-        'Programming Language :: Python :: Implementation :: PyPy',
-        'Typing :: Typed',
-    ],
-)
diff --git a/src/outcome/_version.py b/src/outcome/_version.py
index 735885d..45e2e33 100644
--- a/src/outcome/_version.py
+++ b/src/outcome/_version.py
@@ -1,4 +1,4 @@
-# This file is imported from __init__.py and exec'd from setup.py
+# This file is imported from __init__.py and parsed by setuptools
 from typing import TYPE_CHECKING
 
 if TYPE_CHECKING: