• Provide a subset of MediaWiki syntax (considering to use Mediawiki2HTML machine)
• <math>...</math> tag for MathJax (rendering LaTeX formulas in browsers)
• <markdown>...</markdown> tag for embedding Markdown markups
• Utilize Pandoc for migrating markups

• Distinguish group users and other users
• rwx-bits:
  • r for reading the page
  • w for editing the page
  • x for creating subpage, e.g. /a/b is a subpage of /a

how DokuWiki do it.

You can't edit the page while another's editing the same page

Set a lock:

• When user gets into edit-page.php Refresh a lock:
• When user hits the preview button Lock is expired:
• It is more then xxx seconds old (xxx: 'LOCK_TIME' in /inc/config.php) Lock is deleted:
• When user hots the save button ToDo:
• Refresh the lock in the background while user is editing page
• Section level locking
• Delete the lock when user hits the cancel button