diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 6d25c85..401e50c 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -9,18 +9,20 @@ jobs:
     runs-on: ubuntu-20.04
     strategy:
       matrix:
-        python: ["3.6", "3.7", "3.8", "3.9", "3.10", "3.11", "3.12", "pypy-3.9"]
+        python: ["3.6", "3.7", "3.8", "3.9", "3.10", "3.11", "3.12", "3.13", "pypy-3.9"]
     name: "Test: Python ${{ matrix.python }}"
     steps:
       - uses: actions/checkout@v4
       - uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python }}
-      - run: |
-          python -m pip install --upgrade pip
-          pip install pytest
-      - run: pip install .
-      - run: pytest -v
+      - uses: pypa/hatch@install
+      - run: hatch test -v --cover --include python=$(echo ${{ matrix.python }} | tr -d '-')
+      - run: hatch run coverage:xml
+      - uses: codecov/codecov-action@v5
+        with:
+          fail_ci_if_error: true
+          token: ${{ secrets.CODECOV_TOKEN }}
   typecheck:
     name: Type check
     runs-on: ubuntu-latest
@@ -28,14 +30,16 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions/setup-python@v5
         with:
-          python-version: "3.12"
-      - run: |
-          python -m pip install --upgrade pip
-          pip install pytest mypy
-      - run: mypy --strict src test
+          python-version: "3.13"
+      - uses: pypa/hatch@install
+      - run: hatch run types:check
   fmt:
-    name: Format
+    name: Format and lint
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - uses: psf/black@stable
+      - uses: actions/setup-python@v5
+        with:
+          python-version: "3.13"
+      - uses: pypa/hatch@install
+      - run: hatch fmt --check
diff --git a/.gitignore b/.gitignore
index bf45d22..62f198a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,4 @@
-*.egg-info
 *.pyc
-build/
 dist/
+.coverage
+coverage.xml
diff --git a/codecov.yml b/codecov.yml
new file mode 100644
index 0000000..35cde5c
--- /dev/null
+++ b/codecov.yml
@@ -0,0 +1,4 @@
+coverage:
+  status:
+    project: off
+    patch: off
diff --git a/pyproject.toml b/pyproject.toml
index aec0487..c34fd7b 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,11 +1,59 @@
-[tool.black]
-line-length = 100
-exclude = '''
-/(
-   \.git
- | \.github
- | .*\.egg-info
- | build
- | dist
- )/
-'''
+[build-system]
+requires = ["hatchling"]
+build-backend = "hatchling.build"
+
+[project]
+name = "bin2coe"
+authors = [
+  { name = "Anish Athalye", email = "me@anishathalye.com" },
+]
+description = "A tool to convert binary files to COE files"
+readme = "README.md"
+requires-python = ">=3.6"
+classifiers = [
+  "Development Status :: 5 - Production/Stable",
+  "Intended Audience :: Developers",
+  "License :: OSI Approved :: MIT License",
+  "Programming Language :: Python :: 3",
+  "Topic :: Utilities",
+]
+keywords = ["xilinx", "coe", "bram"]
+dynamic = ["version"]
+
+[project.scripts]
+bin2coe = "bin2coe.cli:main"
+
+[project.urls]
+homepage = "https://github.com/anishathalye/bin2coe"
+repository = "https://github.com/anishathalye/bin2coe.git"
+issues = "https://github.com/anishathalye/bin2coe/issues"
+
+[tool.hatch.version]
+path = "src/bin2coe/__init__.py"
+
+[[tool.hatch.envs.hatch-test.matrix]]
+python = ["3.6", "3.7", "3.8", "3.9", "3.10", "3.11", "3.12", "3.13", "pypy3.9"]
+
+[tool.hatch.envs.types]
+extra-dependencies = [
+  "pytest",
+  "mypy>=1.0.0",
+]
+
+[tool.hatch.envs.types.scripts]
+check = "mypy --strict --install-types --non-interactive {args:src tests}"
+
+[tool.hatch.envs.coverage]
+detached = true
+dependencies = [
+  "coverage",
+]
+
+[tool.hatch.envs.coverage.scripts]
+html = "coverage html"
+xml = "coverage xml"
+
+[tool.ruff.lint]
+ignore = [
+  "FA100",
+]
diff --git a/setup.py b/setup.py
deleted file mode 100644
index 2debebd..0000000
--- a/setup.py
+++ /dev/null
@@ -1,52 +0,0 @@
-from setuptools import setup, find_packages
-from os import path
-import re
-
-
-here = path.dirname(__file__)
-
-
-with open(path.join(here, "README.md"), encoding="utf-8") as f:
-    long_description = f.read()
-
-
-def read(*names, **kwargs):
-    with open(path.join(here, *names), encoding=kwargs.get("encoding", "utf8")) as fp:
-        return fp.read()
-
-
-def find_version(*file_paths):
-    version_file = read(*file_paths)
-    version_match = re.search(r"^__version__ = ['\"]([^'\"]*)['\"]", version_file, re.M)
-    if version_match:
-        return version_match.group(1)
-    raise RuntimeError("Unable to find version string.")
-
-
-setup(
-    name="bin2coe",
-    python_requires=">=3.4",
-    version=find_version("src", "bin2coe", "__init__.py"),
-    description="A tool to convert binary files to COE files",
-    long_description=long_description,
-    long_description_content_type="text/markdown",
-    url="https://github.com/anishathalye/bin2coe",
-    author="Anish Athalye",
-    author_email="me@anishathalye.com",
-    license="MIT",
-    classifiers=[
-        "Development Status :: 5 - Production/Stable",
-        "Intended Audience :: Developers",
-        "License :: OSI Approved :: MIT License",
-        "Programming Language :: Python :: 3",
-        "Topic :: Utilities",
-    ],
-    keywords="xilinx coe bram",
-    packages=find_packages("src"),
-    package_dir={"": "src"},
-    entry_points={
-        "console_scripts": [
-            "bin2coe=bin2coe.cli:main",
-        ],
-    },
-)
diff --git a/src/bin2coe/cli.py b/src/bin2coe/cli.py
index a689cf0..ab9e36c 100644
--- a/src/bin2coe/cli.py
+++ b/src/bin2coe/cli.py
@@ -1,9 +1,8 @@
-from .convert import convert
-from argparse import ArgumentParser
 import sys
+from argparse import ArgumentParser
+from typing import NoReturn
 
-
-from typing import NoReturn, BinaryIO
+from bin2coe.convert import convert
 
 
 def main() -> None:
@@ -19,15 +18,15 @@ def main() -> None:
     options = parser.parse_args()
 
     # check radix
-    if not (2 <= options.radix <= 36):
+    if not (2 <= options.radix <= 36):  # noqa: PLR2004
         error("unsupported radix, must be between 2 and 36")
-    if options.mem and not options.radix in [2, 16]:
+    if options.mem and options.radix not in [2, 16]:
         error("mem requires radix 2 or 16")
 
     # check width
-    if not 8 <= options.width:
+    if not options.width >= 8:  # noqa: PLR2004
         error("width must be >= 8")
-    if not options.width & (options.width - 1) == 0:
+    if options.width & options.width - 1 != 0:
         error("width must be a power of 2")
 
     # if fill is specified, then depth must be specified too; otherwise, depth
@@ -41,7 +40,7 @@ def main() -> None:
         try:
             fill = int(options.fill, options.radix)
         except ValueError:
-            error("invalid fill ({}) for radix ({})".format(options.fill, options.radix))
+            error(f"invalid fill ({options.fill}) for radix ({options.radix})")
 
     with open(options.input, "rb") as f:
         data = f.read()
@@ -54,26 +53,20 @@ def main() -> None:
         if bits % options.width != 0:
             extra = options.width - bits % options.width
             if extra % 8 != 0:
-                error("cannot infer depth, {} total bits, width {}".format(bits, options.width))
+                error(f"cannot infer depth, {bits} total bits, width {options.width}")
             extra_words = extra // 8
             data = data + bytes(extra_words)
             bits = 8 * len(data)
         depth = bits // options.width
+    elif fill is None:
+        if bits != options.width * depth:
+            error(f"memory size / file size mismatch: {depth} x {options.width} bit != {bits}")
     else:
-        # validate depth
-        if fill is None:
-            if bits != options.width * depth:
-                error(
-                    "memory size / file size mismatch: {} x {} bit != {}".format(
-                        depth, options.width, bits
-                    )
-                )
-        else:
-            # make sure it fills an integer number of words
-            if bits % options.width != 0:
-                error("data must fill an integer number of words")
-            if bits > options.width * depth:
-                error("memory size too small: {} x {} bit < {}".format(depth, options.width, bits))
+        # make sure it fills an integer number of words
+        if bits % options.width != 0:
+            error("data must fill an integer number of words")
+        if bits > options.width * depth:
+            error(f"memory size too small: {depth} x {options.width} bit < {bits}")
 
     with open(options.output, "wb") as f:
         convert(
@@ -89,5 +82,5 @@ def main() -> None:
 
 
 def error(msg: str) -> NoReturn:
-    print("error: {}".format(msg), file=sys.stderr)
-    exit(1)
+    print(f"error: {msg}", file=sys.stderr)  # noqa: T201
+    sys.exit(1)
diff --git a/src/bin2coe/convert.py b/src/bin2coe/convert.py
index 671ee1a..4a64c90 100644
--- a/src/bin2coe/convert.py
+++ b/src/bin2coe/convert.py
@@ -1,4 +1,4 @@
-from typing import Iterable, TypeVar, BinaryIO, List, Iterator, Optional
+from typing import BinaryIO, Iterable, Iterator, List, Optional, TypeVar
 
 T = TypeVar("T")
 
@@ -14,7 +14,7 @@ def chunks(it: Iterable[T], n: int) -> Iterator[List[T]]:
         yield res
 
 
-def word_to_int(word: List[int], little_endian: bool) -> int:
+def word_to_int(word: List[int], *, little_endian: bool) -> int:
     if not little_endian:
         word = list(reversed(word))
     value = 0
@@ -26,7 +26,8 @@ def word_to_int(word: List[int], little_endian: bool) -> int:
 def format_int(num: int, base: int, pad_width: int = 0) -> str:
     chars = "0123456789abcdefghijklmnopqrstuvwxyz"
     if num < 0:
-        raise ValueError("negative numbers not supported")
+        msg = "negative numbers not supported"
+        raise ValueError(msg)
     res = []
     res.append(chars[num % base])
     while num >= base:
@@ -44,12 +45,13 @@ def convert(
     depth: int,
     fill: Optional[int],
     radix: int,
+    *,
     little_endian: bool = True,
     mem: bool = False,
 ) -> None:
     pad_width = len(format_int(2**width - 1, radix))
     if not mem:
-        output.write("memory_initialization_radix = {};\n".format(radix).encode("utf8"))
+        output.write(f"memory_initialization_radix = {radix};\n".encode())
         output.write(b"memory_initialization_vector =\n")
     rows = 0
     for word in chunks(data, width // 8):
@@ -57,10 +59,12 @@ def convert(
             if not mem:
                 output.write(b",")
             output.write(b"\n")
-        output.write(format_int(word_to_int(word, little_endian), radix, pad_width).encode("utf8"))
+        output.write(format_int(word_to_int(word, little_endian=little_endian), radix, pad_width).encode("utf8"))
         rows += 1
     if rows < depth:
-        assert fill is not None
+        if fill is None:
+            msg = "fill must not be 'None' if memory is not filled by values"
+            raise ValueError(msg)
         while rows < depth:
             if not mem:
                 output.write(b",")
diff --git a/tests/__init__.py b/tests/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/test/bin2coe/test_convert.py b/tests/test_convert.py
similarity index 97%
rename from test/bin2coe/test_convert.py
rename to tests/test_convert.py
index d44e201..0e27483 100644
--- a/test/bin2coe/test_convert.py
+++ b/tests/test_convert.py
@@ -1,7 +1,6 @@
-from bin2coe.convert import *
 import io
 
-import pytest
+from bin2coe.convert import chunks, convert
 
 
 def test_chunks() -> None: