SciPy on Heroku with Inability to Deploy Conda

Question

My setup:

• Heroku
• Python 2.7.6
• Django 1.8

I have a Conda Buildpack assembly according to:

https://devcenter.heroku.com/articles/python-c-deps 

Here are my conda requirements:

 $ cat conda-requirements.txt cryptography scipy numpy gcc libffi 

Here is the error that I see after trying git push:

 remote: gcc -pthread -fno-strict-aliasing -g -O2 -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -fPIC -DUSE__THREAD -I/usr/include/ffi -I/usr/include/libffi -I/app/.heroku/miniconda/include/python2.7 -cc/_cffi_backend.c -o build/temp.linux-x86_64-2.7/c/_cffi_backend.o remote: c/_cffi_backend.c:15:17: fatal error: ffi.h: No such file or directory remote: #include <ffi.h> remote: ^ remote: compilation terminated. remote: error: command 'gcc' failed with exit status 1 

This is pretty confusing because I already have libffi in my cond requirements, and yet it is the same one that doesn't work. Googling shows that some other people have the same error, while others do not. Any thoughts / suggestions appreciated!

Answer 1

In the ticket that I opened for this problem, it was suggested :

You need to install the libffi-dev system package (or your OS equivalent); on debian / ubuntu, e.g. apt-get install libffi-dev .