diff --git a/.gitignore b/.gitignore
index b25c15b..8b25d04 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,2 @@
 *~
+brminv
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..05d73e6
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,4 @@
+
+.PHONY: backend
+backend:
+	make -C backend
diff --git a/backend/.gitignore b/backend/.gitignore
new file mode 100644
index 0000000..6b15819
--- /dev/null
+++ b/backend/.gitignore
@@ -0,0 +1 @@
+frontend.scm
diff --git a/backend/Makefile b/backend/Makefile
index 0105276..f16a2f8 100644
--- a/backend/Makefile
+++ b/backend/Makefile
@@ -1,11 +1,11 @@
 
 BRMINV_SOURCES=brminv.scm frontend.import.scm
 
-brminv: $(BRMINV_SOURCES)
-	touch brminv
+../brminv: $(BRMINV_SOURCES)
+	touch ../brminv
 
 frontend.o: frontend.import.scm
 frontend.import.scm: frontend.scm
 .PHONY: frontend.scm
 frontend.scm:
-	cd ../frontend && npm run build && csi -b -q ../tools/schemify-tree.scm -- ../frontend/dist frontend frontend-lookup
+	cd ../frontend && npm run build && cd ../backend && csi -b -q ../tools/schemify-tree.scm -- ../frontend/dist frontend frontend-lookup
diff --git a/tools/schemify-tree.scm b/tools/schemify-tree.scm
index f55dac7..46acd37 100644
--- a/tools/schemify-tree.scm
+++ b/tools/schemify-tree.scm
@@ -14,7 +14,7 @@
 	    (cdr args)))))
 
 (define args (get-argv))
-(when (not (eq? (length args) 1))
+(when (< (length args) 1)
   (display "usage: schemify-tree dir")
   (newline)
   (exit 1))