diff --git a/gptc/__main__.py b/gptc/__main__.py
index cfabe87..2e01389 100644
--- a/gptc/__main__.py
+++ b/gptc/__main__.py
@@ -6,48 +6,53 @@ import json
 import sys
 import gptc
 
-parser = argparse.ArgumentParser(
-    description="General Purpose Text Classifier", prog="gptc"
-)
-subparsers = parser.add_subparsers(dest="subparser_name", required=True)
+def main():
+    parser = argparse.ArgumentParser(
+        description="General Purpose Text Classifier", prog="gptc"
+    )
+    subparsers = parser.add_subparsers(dest="subparser_name", required=True)
 
-compile_parser = subparsers.add_parser("compile", help="compile a raw model")
-compile_parser.add_argument("model", help="raw model to compile")
-compile_parser.add_argument("--max-ngram-length", "-n", help="maximum ngram length", type=int, default=1)
+    compile_parser = subparsers.add_parser("compile", help="compile a raw model")
+    compile_parser.add_argument("model", help="raw model to compile")
+    compile_parser.add_argument("--max-ngram-length", "-n", help="maximum ngram length", type=int, default=1)
 
-classify_parser = subparsers.add_parser("classify", help="classify text")
-classify_parser.add_argument("model", help="compiled model to use")
-classify_parser.add_argument("--max-ngram-length", "-n", help="maximum ngram length", type=int, default=1)
-group = classify_parser.add_mutually_exclusive_group()
-group.add_argument(
-    "-j",
-    "--json",
-    help="output confidence dict as JSON (default)",
-    action="store_true",
-)
-group.add_argument(
-    "-c",
-    "--category",
-    help="output most likely category or `None`",
-    action="store_true",
-)
+    classify_parser = subparsers.add_parser("classify", help="classify text")
+    classify_parser.add_argument("model", help="compiled model to use")
+    classify_parser.add_argument("--max-ngram-length", "-n", help="maximum ngram length", type=int, default=1)
+    group = classify_parser.add_mutually_exclusive_group()
+    group.add_argument(
+        "-j",
+        "--json",
+        help="output confidence dict as JSON (default)",
+        action="store_true",
+    )
+    group.add_argument(
+        "-c",
+        "--category",
+        help="output most likely category or `None`",
+        action="store_true",
+    )
 
-args = parser.parse_args()
+    args = parser.parse_args()
 
-with open(args.model, "r") as f:
-    model = json.load(f)
+    with open(args.model, "r") as f:
+        model = json.load(f)
 
-if args.subparser_name == "compile":
-    print(json.dumps(gptc.compile(model, args.max_ngram_length)))
-else:
-    classifier = gptc.Classifier(model, args.max_ngram_length)
-
-    if sys.stdin.isatty():
-        text = input("Text to analyse: ")
+    if args.subparser_name == "compile":
+        print(json.dumps(gptc.compile(model, args.max_ngram_length)))
     else:
-        text = sys.stdin.read()
+        classifier = gptc.Classifier(model, args.max_ngram_length)
 
-    if args.category:
-        print(classifier.classify(text))
-    else:
-        print(json.dumps(classifier.confidence(text)))
+        if sys.stdin.isatty():
+            text = input("Text to analyse: ")
+        else:
+            text = sys.stdin.read()
+
+        if args.category:
+            print(classifier.classify(text))
+        else:
+            print(json.dumps(classifier.confidence(text)))
+
+
+if __name__ == "__main__":
+    main()
diff --git a/pyproject.toml b/pyproject.toml
new file mode 100644
index 0000000..666d2da
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,29 @@
+[build-system]
+requires = ["setuptools>=61.0.0", "wheel"]
+build-backend = "setuptools.build_meta"
+
+[project]
+name = "gptc"
+version = "2.0.0"
+description = "General-purpose text classifier"
+readme = "README.md"
+authors = [{ name = "Samuel Sloniker", email = "sam@kj7rrv.com"}]
+license = { file = "LICENSE" }
+classifiers = [
+    "Programming Language :: Python",
+    "Programming Language :: Python :: 3",
+    "Development Status :: 5 - Production/Stable",
+    "License :: OSI Approved :: GNU Lesser General Public License v3 or later (LGPLv3+)",
+    "Operating System :: OS Independent",
+]
+dependencies = []
+requires-python = ">=3.7"
+
+[project.urls]
+Homepage = "https://git.kj7rrv.com/kj7rrv/gptc"
+
+[project.scripts]
+gptc = "gptc.__main__:main"
+
+[tool.setuptools]
+packages = ["gptc"]
diff --git a/setup.py b/setup.py
deleted file mode 100644
index 54f4336..0000000
--- a/setup.py
+++ /dev/null
@@ -1,17 +0,0 @@
-import setuptools
-
-with open("README.md", "r") as fh:
-    long_description = fh.read()
-setuptools.setup(
-    name="gptc",
-    version="2.0.0",
-    description="General-purpose text classifier",
-    long_description=long_description,
-    long_description_content_type="text/markdown",
-    packages=setuptools.find_packages(),
-    classifiers=[
-        "Programming Language :: Python :: 3",
-        "Operating System :: OS Independent",
-    ],
-    python_requires=">=3.6",
-)