How to create a custom format?

[fredguth]

Description

Scielo is a publishing platform that requires a JATS 1.1 based xml format.
I need to be able to generate typst-pdf and a scielo xml from my article markdown (template.qmd in the example repo).
I tried to create a Minimum Working Example using the ams-typst as inspiration.
You can find it here: https://github.com/fredguth/quarto_mwe

Using pandoc I got a xml that is very similar to scielo:

❯ pandoc template.qmd \
  --standalone \
  -f markdown \
  -t jats \
  -V jats-type=publishing \
  --citeproc \
  --metadata jid="scielo_journal_id" \
  --bibliography=refs.bib \
  -o output.xml

But I really would like to be able to generate the xml file from a template like the one I created as _extensions/mwe/article.scielo based on https://github.com/jgm/pandoc/blob/main/data/templates/article.jats_publishing

I have no idea how you just add something like....

  format:
      jats-publishing: default

...to your markdown frontmatter and pandoc is run with the article.jats_publishing tempalte. Seems magic to me 🪄

I wanted to be able to just add to frontmatter something like:

    format:
        scielo-jats: default