Tank is produced, created and maintained by Peermore Limited under the direction of Chris Dent.
On the server it is mostly built with Python using TiddlyWeb as the core storage and web infrastructure. Additional functionality is provided by an extensive collection of Tiddlyweb plugins. All the code used is open source; if you'd like to work on Tank or run your own server, feel free.
nodejs is used to provide "real-time" notifications and do server-side rendering of TiddlyWiki formatted text into HTML.
Full text indexing is provided by Whoosh.
TiddlyWeb has a flexible storage system that makes it easy to adapt solutions to current usage. While Tank is being developed a simple store which keeps individual entities as files on disk is used. As the service grows those entities will be migrated to more scalable storage, most likely using PostgreSQL.
All resources in Tank can be manipulated via the API that is built in to Tiddlyweb.
The quality of the Tank service is entirely dependent on feedback from the people who use it. If you have comments please contact us.