I have 4 modules inside node_modules folder where one of them is a custom module. In my package.json file, I have the other 3 modules specified as dependencies. So now when I do npm install node is removing that one custom module from node_modules folder because it is not listed in dependencies inside package.json file. 
Is there anyway to keep this custom module without node deleting it when I do npm install? I've tried to include it in .npmignore file, but node is still deleting it.