diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3d58eba4..84d92c22 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,10 @@ Instructions: Add a subsection under `[Unreleased]` for additions, fixes, change
 
 ## [Unreleased]
 
+### Fixed
+
+- Fix bug with packaging core pretext resources that prevented most recent commit from running.
+
 ## [2.41.1] - 2026-06-07
 
 Includes updates to core through commit: [fc8221d](https://github.com/PreTeXtBook/pretext/commit/fc8221d5b8e7027f686729102e169c482fbd1fe5)
diff --git a/pyproject.toml b/pyproject.toml
index bf8a5920..4477a178 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -21,7 +21,7 @@ authors = [
     "Steven Clontz <steven.clontz@gmail.com>",
 ]
 license = "GPL-3.0-or-later"
-include = ["pretext/core/pretext.py", "pretext/core/braille_format.py", "pretext/resources/*.zip", "pretext/resources/*.json"]
+include = ["pretext/core/*.py", "pretext/resources/*.zip", "pretext/resources/*.json"]
 
 # Dependencies
 # ------------
diff --git a/tests/test_utils.py b/tests/test_utils.py
index 28bfa343..96dd1546 100644
--- a/tests/test_utils.py
+++ b/tests/test_utils.py
@@ -1,4 +1,6 @@
+import fnmatch
 import os
+import sys
 import pytest
 from pathlib import Path
 from pretext import utils
@@ -117,6 +119,39 @@ def test_is_earlier_version() -> None:
     assert not utils.is_earlier_version("2.11.5.dev0", "2.11.5")
 
 
+def test_core_modules_included_in_package() -> None:
+    if sys.version_info >= (3, 11):
+        import tomllib
+
+        opener = lambda p: open(p, "rb")  # noqa: E731
+        loader = tomllib.load
+    else:
+        import toml
+
+        opener = lambda p: open(p, "r")  # noqa: E731
+        loader = toml.load
+
+    root = Path(__file__).parent.parent
+    with opener(root / "pyproject.toml") as f:
+        config = loader(f)
+
+    includes: list[str] = config["tool"]["poetry"]["include"]
+
+    core_dir = root / "pretext" / "core"
+    core_files = [
+        str(p.relative_to(root))
+        for p in sorted(core_dir.glob("*.py"))
+        if p.name != "__init__.py"
+    ]
+
+    for rel_path in core_files:
+        covered = any(fnmatch.fnmatch(rel_path, pat) for pat in includes)
+        assert covered, (
+            f"{rel_path} is not covered by any entry in pyproject.toml [tool.poetry] include.\n"
+            f"Add it explicitly or use a glob like 'pretext/core/*.py'."
+        )
+
+
 def test_hash_path(tmp_path: Path) -> None:
     # hash_path should return a 10-character hex string.
     result = utils.hash_path(tmp_path)