heroku running gulp build

i am trying to install a node app onto heroku. My application requires both gulp build and gulp install to be called on the server upon instillation, however i am having troubles doing this. I have tried writing this inside of the package.json:

"scripts":"gulp build && gulp install"

which works at first, but after about an hour the server must restart and recall the script causing for the contents of the server to be rebuilt. this removes all of my content such as newly written blogs or changes.

I have also tried using the heroku toolbelt

heroku run gulp build
heroku run gulp install

However, even though it produces the correct console write lines and looks asif it has made the necessary changes, it hasn't, the server produces an error which proves that the resources haven't been built meaning that the console command didnt make any changes to the actual server files.

Am i missing something out here? Thanks in advance.