diff --git a/Makefile b/Makefile
index 4f8861a..769c5c2 100644
--- a/Makefile
+++ b/Makefile
@@ -269,6 +269,9 @@ version:
 #----------------------------------------------------------------------
 # Main targets...
 
+.PHONY: dep
+dep: DEPENDS.txt
+
 .PHONY: pdf
 pdf: $(MODULE).pdf
 
@@ -342,7 +345,7 @@ tag:
 
 
 .PHONY: all
-all: pdf DEPENDS.txt
+all: pdf dep 
 
 
 # - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
diff --git a/scripts/README.md b/scripts/README.md
index 98f72f7..a467f60 100644
--- a/scripts/README.md
+++ b/scripts/README.md
@@ -389,6 +389,12 @@ $ make-spreads.sh -c <path> ..
 Extract the documentation from photobook.cls which is used to build the 
 photobook.pdf reference manual.
 
+This makes it possible to maintain the documentation and code in a
+single file retaining human readability.
+
+The format is inspired by LaTeX's .dxt format but is far simpler.
+
+
 ```shell
 $ cls2tex.sh --help
 ```