The main feature of the buildpack is posibility to change binaries' versions. For that you need to only change version in
image-optimizer-buildpack.config file (with
Copy link https://github.com/zubroid/heroku-buildpack-image-optims.git and put it to Settings/Buildpack in Heroku dashboard.
Create a config file with
image-optimizer-buildpack.config name and following content:
OPTIPNG_VER="0.7.6" JPEGOPTIM_VER="1.4.4" BUILD_IT=true
and put it in the root of your project.
After every push to heroku it builds Jpegoptim and OptiPNG binaries. To avoid it in image-optimizer-buildpack.config file in your project change.
P.S. Change it olny after first push.
Copy the snippet above into CLI.