diff --git a/docs/flatpak.rst b/docs/flatpak.rst
new file mode 100644
index 0000000..6c40a9b
--- /dev/null
+++ b/docs/flatpak.rst
@@ -0,0 +1,25 @@
+=======
+Flatpak
+=======
+
+Flathub's builders don't allow internet access during the build; everything that
+goes into the build must be specified in the manifest. This means meson
+submodules won't work. Instead, you need to install blueprint-compiler as
+a module in your flatpak manifest:
+
+.. code-block:: json
+
+   {
+     "name": "blueprint-compiler",
+     "buildsystem": "meson",
+     "sources": [
+       {
+         "type": "git",
+         "url": "https://gitlab.gnome.org/jwestman/blueprint-compiler",
+         "branch": "main"
+       }
+     ]
+   }
+
+You can keep the submodule configuration--Meson will ignore it if
+blueprint-compiler is already installed.
\ No newline at end of file
diff --git a/docs/index.rst b/docs/index.rst
index 4be1483..1b2ec6e 100644
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -9,6 +9,7 @@ Blueprint is a markup language and compiler for GTK 4 user interfaces.
 
    setup
    translations
+   flatpak
    examples