# Clone reason-scripts locally
$ git clone [email protected]:reasonml-community/reason-scripts.git
# cd into the new repo
$ cd reason-scripts
# Add the upstream create-react-app repo
$ git remote add upstream [email protected]:facebook/create-react-app.git
# Fetch the remote tag names, we'll need them to determine what version to merge
$ git fetch upstream
# List all the tags we have, we'll find one suitable for merging into reason-scripts
$ git tag --list
# Look for the latest react-scripts tag (ex. [email protected]) and create a branch from it
$ git checkout tags/[email protected] -b upstream-master
# Create a new branch from upstream only consisting of the react-scripts package
$ git subtree split --prefix=packages/react-scripts -b upstream-react-scripts
# Checkout our new react-scripts branch
$ git checkout upstream-react-scripts
# Make sure everything is correct and it's really only the react-scripts package
$ ls
# Checkout master again so we can start the merge!
$ git checkout master
# Do the merge!!!
$ git merge upstream-react-scriptsAdapted from Forking a sub directory of a repository on GitHub and making it part of my own repo