diff --git a/pyproject.toml b/pyproject.toml
new file mode 100755
index 0000000..55a3245
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,26 @@
+[build-system]
+requires = ["setuptools>=61.0"]
+build-backend = "setuptools.build_meta"
+[project]
+name = "AV-98"
+dynamic = ["version"]
+description = "Command line Gemini client"
+authors = [{name="Solderpunk", email="solderpunk@posteo.net"}]
+classifiers = [
+	"License :: OSI Approved :: BSD License",
+	"Programming Language :: Python :: 3 :: Only",
+	"Topic :: Communications",
+	"Intended Audience :: End Users/Desktop",
+	"Environment :: Console",
+	"Development Status :: 5 - Production/Stable",
+]
+[project.urls]
+Homepage = "https://tildegit.org/solderpunk/AV-98/"
+Issues = "https://tildegit.org/solderpunk/AV-98/issues"
+[project.scripts]
+av98 = "av98.av98:main"
+[project.optional-dependencies]
+tofu = ["cryptography"]
+colour = ["ansiwrap"]
+[tool.setuptools.dynamic]
+version = {attr = "av98.__version__"}
diff --git a/setup.py b/setup.py
deleted file mode 100755
index 210bebd..0000000
--- a/setup.py
+++ /dev/null
@@ -1,23 +0,0 @@
-from setuptools import setup
-
-setup(
-    name='AV-98',
-    version='1.0.2dev',
-    description="Command line Gemini client.",
-    author="Solderpunk",
-    author_email="solderpunk@sdf.org",
-    url='https://tildegit.org/solderpunk/AV-98/',
-    classifiers=[
-        'License :: OSI Approved :: BSD License',
-        'Programming Language :: Python :: 3 :: Only',
-        'Topic :: Communications',
-        'Intended Audience :: End Users/Desktop',
-        'Environment :: Console',
-        'Development Status :: 4 - Beta',
-    ],
-    py_modules = ["av98"],
-    entry_points={
-        "console_scripts": ["av98=av98:main"]
-    },
-    install_requires=[],
-)
diff --git a/src/av98/__init__.py b/src/av98/__init__.py
new file mode 100644
index 0000000..bda1b9c
--- /dev/null
+++ b/src/av98/__init__.py
@@ -0,0 +1 @@
+__version__ = "1.1.0dev"
diff --git a/av98.py b/src/av98/av98.py
similarity index 99%
rename from av98.py
rename to src/av98/av98.py
index 95706f5..5981812 100755
--- a/av98.py
+++ b/src/av98/av98.py
@@ -40,10 +40,11 @@ try:
 except ModuleNotFoundError:
     import textwrap
 
-from cache import Cache
-from tofu import TofuStore
-from clientcerts import ClientCertificateManager
-import util
+from av98 import __version__
+from av98.cache import Cache
+from av98.tofu import TofuStore
+from av98.clientcerts import ClientCertificateManager
+import av98.util as util
 
 _VERSION = "1.1.0dev"
 
@@ -1380,7 +1381,7 @@ current gemini browsing session."""
 
     def do_version(self, line):
         """Display version information."""
-        print("AV-98 " + _VERSION)
+        print("AV-98 " + __version__)
 
     ### The end!
     def do_quit(self, *args):
diff --git a/cache.py b/src/av98/cache.py
similarity index 100%
rename from cache.py
rename to src/av98/cache.py
diff --git a/clientcerts.py b/src/av98/clientcerts.py
similarity index 99%
rename from clientcerts.py
rename to src/av98/clientcerts.py
index f7c7092..9627100 100644
--- a/clientcerts.py
+++ b/src/av98/clientcerts.py
@@ -4,7 +4,7 @@ import os
 import os.path
 import uuid
 
-import util
+import av98.util as util
 
 ui_out = logging.getLogger("av98_logger")
 
diff --git a/tofu.py b/src/av98/tofu.py
similarity index 100%
rename from tofu.py
rename to src/av98/tofu.py
diff --git a/util.py b/src/av98/util.py
similarity index 100%
rename from util.py
rename to src/av98/util.py