diff --git a/Makefile b/Makefile
index 0a3e13734d7e4e2245a1d25627feeb604435dda3..7d4b9ded2d42dbfc65911cfd4b870be27654ec05 100644
--- a/Makefile
+++ b/Makefile
@@ -8,10 +8,11 @@ target := gh-pages
 message := Release: $(shell date)
 
 # environment vars
-NODE_ENV := development
+PORT ?= 3000
+NODE_ENV ?= development
 
 # export vars
-export NODE_ENV
+.EXPORT_ALL_VARIABLES:
 
 # targets
 .PHONY: ? deps purge dist clean deploy