Why use a buildpack on heroku?

Question

I have run across more and more references to buildpacks for heroku apps. Other then needed a buildpack that is not support by heroku, why define this parameter in the app creation? I have see references to speed increases for NPM using caching. Some context would help.

Answer 1

If you are running one of Heroku's supported languages, and not encountering any bugs, than I certainly wouldn't bother with a custom buildpack. But, if either of those are not true, a buildpack gives you the tools to fix the situation yourself. More info here: https://devcenter.heroku.com/articles/buildpacks

Answer 2

I build Ruby apps and got fed up of have to run rake db:migrate whenever I deploy a development application to Heroku so I tweaked the standard Ruby buildpack to add in this step and use it when I deploy my applications. I you have something that you typically perform 'around' a deployment then it's something that suitable for incorporating into a buildpack.