diff --git a/Makefile b/Makefile
index b7c98511..c1e79ec1 100644
--- a/Makefile
+++ b/Makefile
@@ -1,12 +1,16 @@
 SHELL := /bin/bash
 
-connectionString=pg://postgres:5432@localhost/postgres
+connectionString=pg://
 
 params := $(connectionString)
 
 node-command := xargs -n 1 -I file node file $(params)
 
 .PHONY : test test-connection test-integration bench test-native build/default/binding.node
+
+help:
+	echo "make test-all connectionString=pg://<your connection string>"
+
 test: test-unit 
 
 test-all: test-unit test-integration test-native test-binary
diff --git a/test/cli.js b/test/cli.js
index c35df8ef..45bb5ae7 100644
--- a/test/cli.js
+++ b/test/cli.js
@@ -1,4 +1,14 @@
-var config = require(__dirname + '/../lib/utils').parseConnectionString(process.argv[2])
+var config = {};
+if(process.argv[2]) {
+  config = require(__dirname + '/../lib/utils').parseConnectionString(process.argv[2]);
+}
+//TODO use these environment variables in lib/ code
+//http://www.postgresql.org/docs/8.4/static/libpq-envars.html
+config.host = config.host || process.env['PGHOST'] || process.env['PGHOSTADDR'];
+config.port = config.port || process.env['PGPORT'];
+config.database = config.database || process.env['PGDATABASE'];
+config.user = config.user || process.env['PGUSER'];
+config.password = config.password || process.env['PGPASSWORD'];
 
 for(var i = 0; i < process.argv.length; i++) {
   switch(process.argv[i].toLowerCase()) {