Symfony: how to setup a development environment for bundles

I want to create a new bundle my-bundle that I can use withing many other Symfony 3 apps that I have, such as my-app with the flowing dir structure.

projects
  my-app
    composer.json
  my-bundle
    composer.json

my-app/composer.json

"require": {
    "my-bundle": "*"
...

"repositories": [
  {
    "type": "path",
    "url": "../my-bundle",
      "options": {
          "symlink": false
      }
  },
...

my-bundle/composer.json

  "require": {
    "symfony/cache": "^3.*"
...

When I run the application it throws a ServiceNotFoundException:

The service "mybundle.some_service" has a dependency on a non-existent service "cache.app".

My 1st question is: why the service is not found although the dependency was installed by my-bundle inside vendor/my/bundle/vendor/symfony/symfony/src/Symfony/Bundle/FrameworkBundle/Resources/config/cache.xml

Second question: why composer install didn't install the required symfony/cache bundle inside of my-app?