Instead of creating a new repository, you can tell composer to use any local path:
https://getcomposer.org/doc/05-repositories.md#path
For instance, lets say that you have your PHP projects under ~/devel/projects
You may have your main project in ~/devel/projects/main_project, and your “local package” in ~/devel/projects/local_package
Define your composer configuration for the local package. In ~/devel/projects/local_package/composer.json.
{
"name": "your_vendor_id/your_local_package",
...
}
Then, you can edit ~/devel/projects/main_project/composer.json and link to your local package via path repo:
"repositories": [
{
"type": "path",
"url": "../local_package",
"options": {
"symlink": true
}
}
],
"require": {
"your_vendor_id/your_local_package": "dev-master",
...
}
More info on this link (not written by me but has a good explanation on this subject):
https://carlosbuenosvinos.com/working-at-the-same-time-in-a-project-and-its-dependencies-composer-and-path-type-repository/