diff --git a/.github/workflows/cd.yml b/.github/workflows/cd.yml
index ead459d..126376e 100644
--- a/.github/workflows/cd.yml
+++ b/.github/workflows/cd.yml
@@ -31,10 +31,11 @@ jobs:
 
       - uses: hynek/build-and-inspect-python-package@v2
 
-  publish:
+  test-publish:
     needs: [dist]
-    name: Publish to PyPI
-    environment: pypi
+    name: Publish to TestPyPI
+    environment:
+      name: testpypi
     permissions:
       id-token: write
     runs-on: ubuntu-latest
@@ -49,6 +50,21 @@ jobs:
       - uses: pypa/gh-action-pypi-publish@release/v1
         if: github.event_name == 'release' && github.event.action == 'published'
         with:
-          # Remember to tell (test-)pypi about this repo before publishing
-          # Remove this line to publish to PyPI
           repository-url: https://test.pypi.org/legacy/
+
+  publish:
+    needs: [test-publish]
+    name: Publish to PyPI
+    environment: pypi
+    permissions:
+      id-token: write
+    runs-on: ubuntu-latest
+    if: github.event_name == 'release' && github.event.action == 'published'
+
+    steps:
+      - uses: actions/download-artifact@v4
+        with:
+          name: Packages
+          path: dist
+
+      - uses: pypa/gh-action-pypi-publish@release/v1
diff --git a/conftest.py b/conftest.py
new file mode 100644
index 0000000..4a9f688
--- /dev/null
+++ b/conftest.py
@@ -0,0 +1,36 @@
+"""Doctest configuration."""
+
+import platform
+from doctest import ELLIPSIS, NORMALIZE_WHITESPACE
+from importlib.util import find_spec
+
+from sybil import Sybil
+from sybil.parsers.rest import DocTestParser, PythonCodeBlockParser, SkipParser
+
+# TODO: stop skipping doctests on Windows when there is uniform support for
+#       numpy 2.0+ scalar repr. On windows it is printed as 1.0 instead of
+#       `np.float64(1.0)`.
+parsers = (
+    [DocTestParser(optionflags=ELLIPSIS | NORMALIZE_WHITESPACE)]
+    if platform.system() != "Windows"
+    else []
+) + [
+    PythonCodeBlockParser(),
+    SkipParser(),
+]
+
+pytest_collect_file = Sybil(
+    parsers=parsers,
+    patterns=["*.rst", "*.py"],
+).pytest()
+
+
+# TODO: via separate optional_deps package
+HAS_ASTROPY = find_spec("astropy") is not None
+HAS_GALA = find_spec("gala") is not None
+
+collect_ignore_glob = []
+if not HAS_ASTROPY:
+    collect_ignore_glob.append("src/unxt/_interop/unxt_interop_astropy/*")
+if not HAS_GALA:
+    collect_ignore_glob.append("src/unxt/_interop/unxt_interop_gala/*")
diff --git a/pyproject.toml b/pyproject.toml
index 8767966..ad90256 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -41,7 +41,13 @@
       "sphinx_autodoc_typehints",
       "sphinx_copybutton",
     ]
-    test = ["numpy", "pytest >=6", "pytest-cov >=3"]
+    test = [
+      "numpy",
+      "pytest >=6",
+      "pytest-cov >=3",
+      "pytest-github-actions-annotate-failures",
+      "sybil",
+    ]
 
   [project.urls]
     "Bug Tracker" = "https://github.com/GalacticDynamics/zeroth/issues"
@@ -59,12 +65,18 @@
 
 
 [tool.pytest.ini_options]
-  addopts        = ["--showlocals", "--strict-config", "--strict-markers", "-ra"]
+  addopts = [
+    "--showlocals",
+    "--strict-config",
+    "--strict-markers",
+    "-p no:doctest",    # using sybil
+    "-ra",
+  ]
   filterwarnings = ["error"]
-  log_cli_level  = "INFO"
-  minversion     = "6.0"
-  testpaths      = ["tests"]
-  xfail_strict   = true
+  log_cli_level = "INFO"
+  minversion = "6.0"
+  testpaths = ["tests/", "docs", "src/"]
+  xfail_strict = true
 
 
 [tool.coverage]
@@ -93,9 +105,14 @@
   [tool.ruff.lint]
     extend-select = ["ALL"]
     ignore = [
+      "D203",    # 1 blank line required before class docstring
+      "D213",    # Multi-line docstring summary should start at the second line
+      "FIX002",  # Line contains TODO, consider resolving the issue
       "ISC001",  # Conflicts with formatter
       "PLR09",   # Too many <...>
       "PLR2004", # Magic value used in comparison
+      "TD002",   # Missing author in TODO
+      "TD003"    # Missing issue link on the line following this TODO
     ]
 
     [tool.ruff.lint.per-file-ignores]
diff --git a/src/zeroth/__init__.py b/src/zeroth/__init__.py
index 23339a8..fa398aa 100644
--- a/src/zeroth/__init__.py
+++ b/src/zeroth/__init__.py
@@ -36,7 +36,7 @@ def zeroth(x: Iterable[T], /) -> T:
     '0'
 
     >>> import numpy as np
-    >>> zeroth(np.array([1, 2, 3]))
+    >>> int(zeroth(np.array([1, 2, 3])))
     1
 
     >>> class ReverseIterable: