diff --git a/pyproject.toml b/pyproject.toml
index 503006c..f4a8cfc 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -95,7 +95,7 @@ skip-excluded-dirs = true
 path = "hatch_build.py"
 
 [tool.hatch.build.targets.wheel]
-packages = ["synapse", "nexusos_cli"]
+packages = ["synapse", "nexusos_cli", "modules"]
 
 [tool.hatch.build.targets.wheel.force-include]
 "VERSION" = "synapse/_resources/VERSION"
@@ -112,6 +112,7 @@ include = [
   "/data/playbooks",
   "/docs",
   "/management",
+  "/modules",
   "/nexusos_cli",
   "/scripts",
   "/synapse",
diff --git a/tests/test_packaging_deps.py b/tests/test_packaging_deps.py
index 37dea1e..ec3e4de 100644
--- a/tests/test_packaging_deps.py
+++ b/tests/test_packaging_deps.py
@@ -15,7 +15,7 @@ from pathlib import Path
 import pytest
 
 ROOT = Path(__file__).resolve().parents[1]
-SHIPPED_PACKAGES = ("synapse", "nexusos_cli")
+SHIPPED_PACKAGES = ("synapse", "nexusos_cli", "modules")
 
 # Import name -> distribution name, where PyPI disagrees with the module.
 DISTRIBUTION_OF = {
@@ -32,7 +32,7 @@ DISTRIBUTION_OF = {
 TRANSITIVE = {"starlette", "socketio", "engineio"}
 
 # Modules that ship inside this repo.
-FIRST_PARTY = {"synapse", "nexusos_cli", "management", "bin", "tests"}
+FIRST_PARTY = {"synapse", "nexusos_cli", "modules", "management", "bin", "tests"}
 
 
 def _pyproject() -> dict:
@@ -55,6 +55,12 @@ def _declared() -> set[str]:
     return {_requirement_name(s) for s in specs}
 
 
+def test_wheel_includes_every_shipped_package():
+    wheel = _pyproject()["tool"]["hatch"]["build"]["targets"]["wheel"]
+    configured = set(wheel["packages"])
+    assert configured == set(SHIPPED_PACKAGES)
+
+
 def _imported_modules() -> set[str]:
     """Top-level module names imported anywhere in the shipped packages."""
     found: set[str] = set()
@@ -88,7 +94,7 @@ def test_every_third_party_import_is_a_declared_dependency():
         if DISTRIBUTION_OF.get(module, module).lower().replace("_", "-") not in declared
     )
     assert not missing, (
-        "synapse/nexusos_cli import these, but pyproject.toml declares no "
+        "a shipped package imports these, but pyproject.toml declares no "
         f"distribution for them: {missing}. Add them to [project] dependencies "
         "or an extra (and to DISTRIBUTION_OF here if the names differ)."
     )