Build-before hooks and including my theme via composer

If I’m not mistaken, I’m already attempting what you’re suggesting in that link. I’m using the latest Trellis, Bedrock, and Sage 9. I’ve uncommented the build-before.yml and replaced sage with my theme name. I’m not doing a multisite so I don’t see a need to use a {{ site }} variable as discussed in that link you provided. Unless I’m misunderstanding what you are suggesting. Here is my build-before.yml for reference, though again, it should look pretty much like the default since all I did was replace the word sage:

- name: Run yarn install
  command: yarn install
  connection: local
  args:
    chdir: "{{ project_local_path }}/web/app/themes/my-theme"

- name: Install Composer dependencies
  command: composer install --no-ansi --no-dev --no-interaction --no-progress --optimize-autoloader --no-scripts
  args:
    chdir: "{{ deploy_helper.new_release_path }}/web/app/themes/my-theme"

- name: Compile assets for production
  command: yarn run build:production
  connection: local
  args:
    chdir: "{{ project_local_path }}/web/app/themes/my-theme"

- name: Copy project local files
  synchronize:
    src: "{{ project_local_path }}/web/app/themes/my-theme/dist"
    dest: "{{ deploy_helper.new_release_path }}/web/app/themes/my-theme"
    group: no
    owner: no
    rsync_opts: --chmod=Du=rwx,--chmod=Dg=rx,--chmod=Do=rx,--chmod=Fu=rw,--chmod=Fg=r,--chmod=Fo=r

It’s that second step that seems to be giving me trouble. If I ssh into my dev machine, there is no srv/www/mysite.com/releases/. There is one on the DO droplet, though. I assume that’s the way it’s supposed to be?