{
  //put the file selection part in a closure, so that the list of all files is kept private.
  /*
  select markdown files not beginning with `_`, force contents to Document, and add data parsed from filename.
  */
  allfiles: Tree.filter(., (val, key) => key.endsWith('.md') && !key.startsWith('_') && key !== 'README.md')
    → (items) => Tree.map(items, {value: (value) => Origami.document(value)}) //if I don't use the verbose syntax I get the filename characters as part of value!
    → (items) => Tree.map(items, {value: (value, key) => addFilenameData.js(value, key)})

  /*
    Now convert to html.
  */
  asHtml: Tree.map(allfiles, {
    value: (value) => Origami.mdHtml(value)
    key: (value, key) => `${value.fnd.name}.html`
  })

  renderedPages: Tree.map(asHtml, (page) => <page.ori>(page))

  /*
  Now, I think I have enough to build both the individual pages and the index page!
  */
  index.html: indexPage.ori(asHtml)
  ...renderedPages
}