Use ImageMagick built with libwebp inside a Heroku Cedar environment. This buildpack will download both libraries, build them from source and install them along side your app. Your $PATH and $LD_LIBRARY_PATH will also be updated to use this version of ImageMagick instead of the default Heroku one, which does not currently have libwebp support.
Since this buildpack is building libwebp and ImageMagick from source your first deploy will take a very long time (around 10 mins). However after building once the installed libraries are stored in a cache directory and will be used for all future deploys. If for any reason you want to force a rebuild of libwebp and ImageMagick, please check out the heroku-repo plugin.
This buildpack is meant to be used through heroku-buildpack-multi, so in your app you need to:
heroku config:set BUILDPACK_URL=https://github.com/ddollar/heroku-buildpack-multi
Then create a .buildpacks file inside your app:
https://github.com/nrj/heroku-buildpack-imagemagick-webp
https://github.com/heroku/heroku-buildpack-nodejs
The second line is for a nodejs buildpack, but it can be any other buildpack you want. If it is not working with yours, please report a bug.
You can verify that ImageMagick was built with libwebp support by running the following:
heroku run "identify -list format"
If the output includes WEBP* rw- WebP Image Format (libwebp 0.4.2) then you're all set.
Copyright (c) 2014 Nick Jensen, https://nrj.io Copyright (C) 2012 Heroku, Inc.
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