diff --git a/pyproject.toml b/pyproject.toml
index b25c1a6..7552704 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -5,7 +5,7 @@ build-backend = "setuptools.build_meta"
 [project]
 name = "fiwicontrol"
 version = "0.1.0"
-description = "FiWiControl repo: commands (SSH/ush), lab (USB discovery + INI inventory), power (Acroname/Monsoon)."
+description = "FiWiControl repo: commands (SSH/ush), lab (USB discovery + INI inventory), power (Acroname/Monsoon), flows (async iperf over SSH)."
 readme = "README.md"
 requires-python = ">=3.11"
 license = { file = "LICENSE" }
@@ -16,6 +16,7 @@ dependencies = []
 [project.optional-dependencies]
 dev = ["pytest>=8.0"]
 power = ["brainstem", "pyserial"]
+flows = ["numpy", "scipy", "matplotlib"]
 
 [tool.setuptools]
 package-dir = {"" = "src"}
diff --git a/tests/test_package_layout.py b/tests/test_package_layout.py
index 929caa7..1dac278 100644
--- a/tests/test_package_layout.py
+++ b/tests/test_package_layout.py
@@ -1,7 +1,9 @@
 def test_import_subpackages() -> None:
     import fiwicontrol
     import fiwicontrol.commands
+    import fiwicontrol.flows
     import fiwicontrol.lab
     import fiwicontrol.power
 
     assert fiwicontrol.__version__
+    assert "iperf" in (fiwicontrol.flows.__doc__ or "").lower()