Makefile path weirdness

.gitignore

node_modules

LINUX.txt

vagrant@precise64:/rouge8/tmp/makewtf$ make test
npm install --silent --no-color
echo /bin/sh
/bin/sh
which karma
node_modules/.bin/karma
karma --version
Karma version: 0.12.0

Makefile

export PATH := node_modules/.bin:$(PATH)
export SHELL := /bin/bash

.PHONY: test install-deps

install-deps:
	npm install --silent --no-color

test: install-deps
	echo $(SHELL)
	which karma
	karma --version

OSX.txt

$ make test
npm install --silent --no-color
echo /bin/sh
/bin/sh
which karma
node_modules/.bin/karma
karma --version
make: karma: No such file or directory
make: *** [test] Error 1

package.json

{
  "name": "makewtf",
  "version": "0.0.0",
  "description": "",
  "devDependencies": {
    "karma-cli": "0.0.3",
    "karma": "^0.12.0"
  }
}