How to add Cargo to PATH required for pywinpty when deploying to Heroku?

Question

I am getting the following error on Windows:

Cargo, the Rust package manager, is not installed or is not on PATH.
remote: This package requires Rust and Cargo to compile extensions.

I've installed Rust and cargo is in the path, but the problem persists. Does anybody know why this is happening?

Error message is the same as in this post.

Answer 1

Heroku's stack runs on Ubuntu. Cargo is required by pywinpty but that's a library required for communicating with Windows processes. You may need it for your local environment but you don't need it for Heroku. You should try removing pywinpty from your requirements.txt when you deploy to Heroku.