The Platform

The latest Zooniverse platform consists of a number of services working together.

• Panoptes is the main API endpoint in our platform. This is where user logins happen, and what stores data about projects, workflows, subjects, and classifications. https://zooniverse.github.io/Panoptes
• Cellect is a service that selects a few randomly-chosen subjects for a user to work on next.
• Designator is an alternative to Cellect. It’s written in Elixir with no C-based dependencies. It differentiates by loading and unloading data automatically, and offering options to bias selection to certain sets, either per workflow or even on a per-user basis.
• Caesar is an auxilliary service that deals with subject retirement rules. Panoptes itself comes with a very simple threshold on the number of classifications per subject. Caesar is where we implement any project-specific retirement rules (although obviously we try and generalise when possible). https://zooniverse.github.io/caesar
• ZooEventStats gathers metrics on everything in our platform.
• Aggregation

Services still under development

The following services are still being built and are not yet in active use:

• Warehouse will take over the exporting of classifications for a project.
• Notifications will maintain an open websocket (or long-polling) connection to browsers, so that we get a channel to push notifications to browsers directly.