Building time is excessively high

Hi, I am using TravisCI as my integration server, and this buildpack for deploying to heroku https://github.com/kevinseguin/heroku-buildpack-meteor . There is one step on this procedure which is the build (displays “building meteor app bundle” in travis), and it takes about 8 minutes to complete. And the app is just an out-of-box meteor app. I wanted to know how can I modify this part of the buildpack in order to make it faster, I don’t know what it does but if the “meteor run” command is executed, should’t the only thing that need to be done is to upload the changes, and this command rebuilds the meteor app (as it is on my pc).
I might be completely wrong because I know almost nothing, but there is this uni project that I’m working on and I must have a continuous integration environment set up, and every time I do a simple commit takes about 10 minute for me to receive feedback (if the build was successful or not). Regards

PS. I tried leaving a comment in a commit made by kevinseguin but I didn’t get any response.