diff --git a/README.md b/README.md
index 13b6e76..19fa143 100644
--- a/README.md
+++ b/README.md
@@ -34,7 +34,6 @@ While editing text:
 * `ctrl+=` to zoom in, `ctrl+-` to zoom out, `ctrl+0` to reset zoom
 * `alt+right`/`alt+left` to jump to the next/previous word, respectively
 * mouse drag or `shift` + movement to select text, `ctrl+a` to select all
-* `ctrl+e` to modify the sources
 
 For shortcuts while editing drawings, consult the online help. Either:
 * hover on a drawing and hit `ctrl+h`, or
diff --git a/main.lua b/main.lua
index 13f2d6a..a59c483 100644
--- a/main.lua
+++ b/main.lua
@@ -1,5 +1,13 @@
--- Entrypoint for the app. You can edit this file from within the app if
--- you're careful.
+-- Wrapper that combines the app with a 'source editor' that allows editing
+-- the app in place.
+--
+-- The source editor is a sharp tool. I find it convenient, but I also often
+-- end up in a bad state that requires dropping down to external tools
+-- (editor, file manager) to fix.
+--
+-- Downstream forks provide a better, "freewheeling" experience for editing
+-- apps live. The source editor provides a half-baked experience for editing
+-- some of the primitives used by true freewheeling apps.
 
 -- files that come with LÖVE; we can't edit those from within the app
 utf8 = require 'utf8'
diff --git a/source.lua b/source.lua
index 81eb544..cbbd6cf 100644
--- a/source.lua
+++ b/source.lua
@@ -1,3 +1,10 @@
+-- Source editor that lets me edit the app from within. However, it's a sharp
+-- tool. I find it convenient, but I also often end up in a bad state that
+-- requires dropping down to external tools (editor, file manager) to fix.
+--
+-- Downstream forks provide a better, "freewheeling" experience for editing
+-- apps live. The source editor provides a half-baked experience for editing
+-- some of the primitives used by true freewheeling apps.
 source = {}
 
 Editor_state = {}