----> Node.js app detected

-----> Creating runtime environment



       NPM_CONFIG_LOGLEVEL=error

       NPM_CONFIG_PRODUCTION=true

       NODE_VERBOSE=false

       NODE_ENV=production

       NODE_MODULES_CACHE=true

-----> Installing binaries

       engines.node (package.json):  9.4.0

       engines.npm (package.json):   5.3.0

       engines.yarn (package.json):  1.3.2



       Resolving node version 9.4.0...

       Downloading and installing node 9.4.0...

       Bootstrapping npm 5.3.0 (replacing 5.6.0)...

       npm 5.3.0 installed

       Resolving yarn version 1.3.2...

       Downloading and installing yarn (1.3.2)...

       Installed yarn 1.3.2

-----> Restoring cache

       Skipping cache restore (not-found)

-----> Building dependencies

       Installing node modules (yarn.lock)

       yarn install v1.3.2

       [1/4] Resolving packages...

       [2/4] Fetching packages...

       info fsevents@1.1.1: The platform "linux" is incompatible with this module.

       info "fsevents@1.1.1" is an optional dependency and failed compatibility check. Excluding it from installation.

       [3/4] Linking dependencies...

       warning "webpack > ajv-keywords@1.5.1" has unmet peer dependency "ajv@>=4.10.0".

       [4/4] Building fresh packages...

       $ webpack --config webpack.prod.js

       /bin/sh: 1: webpack: not found

       error Command failed with exit code 127.

       info Visit https://yarnpkg.com/en/docs/cli/install for documentation about this command.

-----> Build failed



       We're sorry this build is failing! You can troubleshoot common issues here:

       https://devcenter.heroku.com/articles/troubleshooting-node-deploys



       If you're stuck, please submit a ticket so we can help:

       https://help.heroku.com/



       Love,

       Heroku



 !     Push rejected, failed to compile Node.js app.

 !     Push failed