diff --git a/docs/Makefile b/docs/Makefile
index 26d3159..2d83913 100644
--- a/docs/Makefile
+++ b/docs/Makefile
@@ -9,12 +9,12 @@
 # Make configuration
 include make.d/prelude.make
 
-# jqt version
-Version := 0.5.1
-
 # Metadata directory
 Metadata := .meta
 
+# jqt version
+Version := 0.5.1
+
 # Do not build to clobber immediately
 ifeq (clobber,$(MAKECMDGOALS))
 ifeq (,$(wildcard $(Metadata)))
@@ -22,6 +22,13 @@ $(error Nothing to clobber)
 endif
 endif
 
+# Do not build to clean immediately
+ifeq (clean,$(filter clean,$(MAKECMDGOALS)))
+ifeq (,$(wildcard $(Metadata)))
+$(error Nothing to clean)
+endif
+endif
+
 # ======================================================================
 -include $(Metadata)/phase1.make
  include make.d/config.make
diff --git a/docs/content/data.md b/docs/content/data.md
index d0bd85a..2bd1290 100644
--- a/docs/content/data.md
+++ b/docs/content/data.md
@@ -5,7 +5,7 @@ title: Managing the data model with jqt
 description: jqt combines one template with one MarkDown document and a data model.
 keywords:  jqt, JSON, YAML, gpp, preprocessing, data model
 updated: "2016-08-28T10:27:09Z"
-use: [content/macros.m, content/LINKS.txt, content/FLOW.txt, "content/opt/[DeIMmnPRT].txt"]
+use: [content/macros.m, content/LINKS.txt, content/FLOW.txt, "content/opt/[DeIMmPRT].txt"]
 ---
 <%include content/macros.m>&
 <%include content/LINKS.txt>&
diff --git a/docs/content/engine.md b/docs/content/engine.md
index 8d0e751..d4e04fa 100644
--- a/docs/content/engine.md
+++ b/docs/content/engine.md
@@ -5,7 +5,7 @@ title: The jqt template engine
 description: jqt orchestrates several shell utilities to transform MarkDown text and YAML or JSON data into a final HTML page.
 keywords:  jqt, jq, YAML, gpp, preprocessing, template engine
 updated: "2016-08-28T10:27:09Z"
-use: [content/macros.m, content/LINKS.txt, content/FLOW.txt, "content/opt/[4CDdeHhIijLMmnPprSTtVw].txt"]
+use: [content/macros.m, content/LINKS.txt, content/FLOW.txt, "content/opt/[4CDdeHhIijLMmPprSTtVw].txt"]
 ---
 <%include content/macros.m>&
 <%include content/LINKS.txt>&
diff --git a/docs/data/snippets.yaml b/docs/data/snippets.md
similarity index 100%
rename from docs/data/snippets.yaml
rename to docs/data/snippets.md
diff --git a/docs/jqt.make b/docs/jqt.make
index 70ef34d..0f917df 100644
--- a/docs/jqt.make
+++ b/docs/jqt.make
@@ -1,21 +1,75 @@
 ########################################################################
+#
 #  Specific makefile for this web site
+#
+# Defined rules for:
+#	$(Metadata)/snippets.json
+#	$(ManPage)
+#	/tmp/help
+# Defined targets:
+# 	all
+# 	clean
+# 	clobber
+# 	init
 
 ########################################################################
 # Data files
 ########################################################################
 
-# Snippets
-$(Metadata)/snippets.json: $(Data)/snippets.yaml \
-| $(Metadata)
+# Declare explicitly modules with -m, -M or -j; this must be decided by a
+# human!
+JQTFLAGS += -msnippets:$(Metadata)/snippets.json
+
+# To define in phase2.make from
+#	find $(Data) -name '*.*'
+
+DataMD    := $(Metadata)/snippets.json
+DataYAML  :=
+DataJSON  :=
+DataCSV   :=
+
+# =========================
+# To move to pathnames.make
+# =========================
+
+#
+# Files derived from $(Data)/*
+#
+
+ifneq (,$(DataMD))
+$(DataMD): $(Metadata)/%.json : $(Data)/%.md | $(Metadata)
 	$(info ==> $@)
 	@jqt -T < $< | yaml2json > $@
+endif
 
-$(DestinationPages): $(Metadata)/snippets.json
+ifneq (,$(DataYAML))
+$(DataYAML): $(Metadata)/%.json : $(Data)/%.yaml | $(Metadata)
+	$(info ==> $@)
+	@yaml2json > $@
+endif
 
-JQTFLAGS += -msnippets:$(Metadata)/snippets.json
+ifneq (,$(DataJSON))
+$(DataJSON): $(Metadata)/%.json : $(Data)/%.yaml | $(Metadata)
+	$(info ==> $@)
+	@jqt -P json < $< > $@
+endif
+
+ifneq (,$(DataCSV))
+$(DataCSV): $(Metadata)/%.json : $(Data)/%.yaml | $(Metadata)
+	$(info ==> $@)
+	@csv2json < $< > $@
+endif
 
-clean:: ; @rm -f $(Metadata)/snippets.json
+DataFiles := $(DataMD) $(DataYAML) $(DataJSON) $(DataCSV)
+
+ifneq (,$(DataFiles))
+
+$(DestinationPages): $(DataFiles)
+
+init::
+	@$(MAKE) -s $(DataFiles)
+
+endif
 
 ########################################################################
 # Build pages options
@@ -29,7 +83,9 @@ JQTFLAGS += 					\
 	-5 					\
 	--toc-depth=4				\
 	-iblocks/filters			\
-	-msections:$(Metadata)/sections.json	\
+
+# only for derived nodes?
+#	-msections:$(Metadata)/sections.json	\
 
 ########################################################################
 # Generate man page for jqt
diff --git a/docs/make.d/pages.make b/docs/make.d/pages.make
index 35ec960..81e07a8 100644
--- a/docs/make.d/pages.make
+++ b/docs/make.d/pages.make
@@ -18,8 +18,8 @@
 # Create makefile containing rules for all HTML files
 ########################################################################
 
-# Rules for each page (depend also on sections.json only to force build)
-$(Metadata)/phase3.make: $(Metadata)/pages.json $(Metadata)/sections.json make.d/pages.make make.d/phase3.jq $(Metadata)/phase2.make
+# Build rules for each page
+$(Metadata)/phase3.make: $(Metadata)/pages.json make.d/pages.make make.d/phase3.jq $(Metadata)/phase2.make
 	$(info ==> $@)
 	@jq --raw-output			\
 	    --arg Metadata $(Metadata)		\
@@ -32,10 +32,11 @@ $(Metadata)/phase3.make: $(Metadata)/pages.json $(Metadata)/sections.json make.d
 # Variables used in $(Metadata)/phase3.make.
 #
 
-JQTFLAGS =					\
-	-I./					\
-	-msite:$(Metadata)/config.json		\
-	-j'$$'pages:$(Metadata)/pages		\
+define JQTFLAGS :=
+	-msite:$(Metadata)/config.json	\
+	-j'$$'pages:$(Metadata)/pages	\
+	-I./
+endef
 
 JQT = jqt $(JQTFLAGS)
 
@@ -88,10 +89,15 @@ touch:
 fresh: clobber
 	@$(MAKE) -s all
 
-init:
+# make all metadata except files derived from $(Data)
+init::
+ifdef MAKE_RESTARTS
+	@:
+else
 	@rm -rf $(Metadata)
 	@$(MAKE) -s $(Metadata)/phase3.make
-
 endif
 
+endif # __phase_3
+
 # vim:ai:sw=8:ts=8:noet:fileencoding=utf8:syntax=make
diff --git a/docs/make.d/pathnames.make b/docs/make.d/pathnames.make
index fe8b23b..89644bc 100644
--- a/docs/make.d/pathnames.make
+++ b/docs/make.d/pathnames.make
@@ -32,6 +32,7 @@ $(Metadata)/phase2.make: make.d/pathnames.make make.d/phase2.jq $(Metadata)/phas
 	     --slurp					\
 	     --raw-output				\
 	     --from-file make.d/phase2.jq		\
+	     --arg DF "$$(find $(Data) -name '*.*')"	\
 	     --arg Content $(Content)			\
 	     --arg Destination $(Destination)		\
 	     --arg Metadata $(Metadata)			\
@@ -99,6 +100,6 @@ $(Metadata)/sections.json: $(Metadata)/pages.json
 	$(info ==> $@)
 	@jq '[.[].section] | unique | map(select(.))' < $< > $@
 
-endif
+endif # __phase_2
 
 # vim:ai:sw=8:ts=8:noet:fileencoding=utf8:syntax=make
diff --git a/docs/make.d/phase2.jq b/docs/make.d/phase2.jq
index 78bf9ba..ea2624a 100644
--- a/docs/make.d/phase2.jq
+++ b/docs/make.d/phase2.jq
@@ -1,4 +1,4 @@
-# phase2.jq --arg Content $(Content) --arg Destination $(Destination) --arg Metadata $(Metadata)
+# phase2.jq --arg Content $(Content) --arg Destination $(Destination) --arg Metadata $(Metadata) --arg DF "$$(find $(Data) -name '*.*')
 # 
 # Generate phase2.make from `find` output.
 
@@ -48,6 +48,16 @@ def mpages($documents):
     | "MetadataPages := " + ($json | join(" ")) + "\n" + mrule
 ;
 
+
+def data($files):
+    ($files / "\n") as $names
+    | [($names[] | select(test(".md$")))] as $DataMD
+    | [($names[] | select(test(".yaml$")))] as $DataYAML
+    | [($names[] | select(test(".json$")))] as $DataJSON
+    | [($names[] | select(test(".csv$")))] as $DataCSV
+    | ""
+;
+
 ########################################################################
 # Output makefile
 ########################################################################
@@ -58,12 +68,14 @@ def mpages($documents):
 | mpaths($paths) as $MetadataPaths
 | dpages($documents) as $DestinationPages 
 | mpages($documents) as $MetadataPages
+| data($DF) as $DataFiles
 |
 "__phase_2 := 1",
 $DestinationPaths,
 $MetadataPaths,
 $DestinationPages,
 $MetadataPages,
+$DataFiles,
 comment
 
 # vim:ts=4:sw=4:ai:et:fileencoding=utf8:syntax=jq