PetScan (previously CatScan) is an external tool that searches an article category (and its subcategories) according to specified criteria to find articles, stubs, images, and categories. It can also be used for finding all articles that belong to two specified categories (the intersection). CatScan was developed by the German Wikipedian
Duesentrieb and is run on
Cloud VPS, as part of Wikimedia Foundation's cloud computing environment.[1] The tool has been rewritten three times by
Magnus Manske, first in
PHP, then in
C++, finally in
Rust.