skin layer	skin PHP and CSS
style layer	wikitext
transclusion layer	templates
database layer	swFilter swQuery swRelation swRelationFilter swExpression
object layer	swWiki	swUser
swRecord
swPersistance	swDB	swBitmap	swParser	swFunction
physical layer	revisions	current	files	cache	indexes	bloom	monogram	queries

Includes in a web request

• index.php
• api.php
• inc/*.php
• inc/functions/*.php
• inc/parsers/*.php
• inc/system-defaults-*.php
• site/configuration.php
• site/functions/*.php
• inc/ramdisk.php
• inc/image.php
• inc/special/[$action].php
• inc or site/skins/[$skin].php

Physical data

Everything site specific is in the site folder.

Do not modify content in the inc folder. It may be erased on update.

Complete representation of the website

• site/revisions/*.txt
• site/files/*.*
• site/functions/*.*
• site/skins/*.*

Cache of current revisions

• site/current/(md5hash).txt
• site/current/(revision).txt

Query cache

• site/queries/*.db

Image cache

• site/cache/*.*

Access logs

• site/logs/

Indexes

• site/indexes/bloom.raw (big binary bitmap)
• site/indexes/monogram.db (monograms)
• site/indexes/records.db (copies of revisions, access is faster than single file)
• site/indexes/urls.db (index of names)

Essential indexes (are recreated immediately if missing

• site/indexes/bloombitmap.txt (bitmap of bloom indexed revisions)
• site/indexes/currentbitmap.txt (bitmap of current revisions)
• site/indexes/deletedbitmap.txt (bitmap of deleted revisions)
• site/indexes/indexedbitmap.txt (bitmap of indexed revisions)
• site/indexes/protectedbitmap.txt (bitmap of protected revisions)

.txt is source file or serialized php object
.db is sqlite3 db or Berkeley db