Add brief docs on editable installs via pip.

doc-source/cli.rst

@@ -8,3 +8,23 @@ whey
 .. click:: whey.__main__:main
 	:prog: whey
 	:nested: none
+
+Editable installs
+------------------
+
+Whey also supports :pep:`660` editable installs via :github:repo:`pip <pypa/pip>`.
+Editable installs allow changes to the project's source code (but not its entry points and other metadata)
+to be automatically reflected when the module is next imported.
+
+To install the project in the current directory in editable mode, run the following command:
+
+.. prompt:: bash
+
+	python3 -m pip install --editable .
+
+See the pip documentation_ for more details.
+
+If using pip's ``--no-build-isolation`` flag [1]_, whey must be installed with the ``editable`` extra, as additional requirements are required for editable installs.
+
+.. _documentation: https://pip.pypa.io/en/stable/cli/pip_install/#cmdoption-e
+.. [1] https://pip.pypa.io/en/stable/cli/pip_install/#cmdoption-no-build-isolation