How to keep a deployment repo for Heroku within a development Git repo and keep them separate?

I think the issue was by ths following , I'm not a 100% sure if what you want is possible, but my theory is that if you can somehow add the fork as a submodule, you would be able to achieve what you want.
Help on forking: http://help.github.com/fork-a-repo/

seems to work fine I have a website on Bluehost and this is very simple to set up. First you need to go into your CPanel and request ssh access.
Then follow this guide for setting up your private key (stays on your computer) and public key (goes in .ssh/authorized_keys on the bluehost server).

*****@******.info [~]# 
*****@******.info [~/git]# mkdir test.git
*****@******.info [~/git]# cd test.git
*****@******.info [~/git/test.git]# pwd
/home1/******/git/test.git
*****@******.info [~/git/test.git]# git init --bare
Initialized empty Git repository in /home1/*******/git/test.git/
*****@******.info [~/www/test.git]# cd hooks
*****@******.info [~/www/test.git]# vi post-receive

#!/bin/sh
GIT_WORK_TREE=/home1/*******/test git checkout -f

*****@******.info [~/www/test.git/hooks]# chmod +x post-receive
*****@******.info [~/www/test.git/hooks]# cd ~
*****@******.infoo [~]# git init test
Initialized empty Git repository in /home1/*******/test/.git/
*****@******.info [~]# exit

[nedwidek@yule ~]$ git init test.git
Initialized empty Git repository in /home/nedwidek/test.git/.git/
[nedwidek@yule ~]$ cd test.git
[nedwidek@yule test.git]$ touch testfile.txt
[nedwidek@yule test.git]$ git add .
[nedwidek@yule test.git]$ git commit -m "testing" .
[master (root-commit) 1d6697c] testing
 0 files changed, 0 insertions(+), 0 deletions(-)
 create mode 100644 testfile.txt
[nedwidek@yule test.git]$ git remote add origin *****@******.info:/home1/*****/git/test.git
[nedwidek@yule test.git]$ git push -u origin master
Counting objects: 5, done.
Writing objects: 100% (3/3), 270 bytes, done.
Total 3 (delta 0), reused 0 (delta 0)
To *****@******.info:/home1/*******/test.git
   f144186..0fd10f8  master -> master
Branch master set up to track remote branch master from origin.

I wish this helpful for you The message you are seeing means that changes have been made to the application that you do not have in your local copy. When you push it's rejected because the Heroku remote is further ahead than yours, so you're right in thinking that your partner has pushed to Heroku without pushing to Github - it's a common scenario since you deploy from your local repository when you deploy to Heroku, unlike a traditional Capistrano deploy which would deploy the code from Github typically.
It's down to you as a team to come up with ways of working which prevent this from occuring, but if you need to get working right now, you can either

wish of those help You're right, that's a pretty common use case. Gitlab uses what it calls Deploy Keys to achieve this (more info here).
I've answered a similar question here.

- 'which ssh-agent || ( apt-get update -y && apt-get install openssh-client -y )'
# Run ssh-agent (inside the build environment)
- eval $(ssh-agent -s)
# Add the SSH key stored in SSH_PRIVATE_KEY variable to the agent store
- ssh-add <(echo "$SSH_PRIVATE_KEY")
- mkdir -p ~/.ssh
- '[[ -f /.dockerenv ]] && echo -e "Host *\n\tStrictHostKeyChecking no\n\n" > ~/.ssh/config'

it should still fix some issue The purpose of the git storage is mostly to let user visualize the differences through tools like git hub, or any other tools that can support diffs, plus by pushing to a remote you also get a remote backup of the flow content. It is not meant to be modified outside of the application, just like you wouldn't bypass an application and go right into it's database and start changing data.