This article is a work in progress. The work is being tracked in this bug.

• Shield is an addon-based experimentation platform with fine-tuned enrollment criteria. The system add-on landed in FF 53.
• For the moment, it sends back data in its own shield type ping, so there's lots of flexibility in data you can collect.
• Uses the Normandy server to serve out study “recipes” (?)
• Annotates the main ping in the environment/experiments block
• The shield system is itself a system add-on, so rolling out changes to the entire system does not require riding release trains
• Strategy and Insights (strategyandinsights@mozilla.com) team are product owners and shepherd the study development and release process along
• Opt-out experiments should be available soon?
• Further reading:
  • https://wiki.mozilla.org/Firefox/SHIELD
  • https://wiki.mozilla.org/Firefox/Shield/Shield_Studies
  • https://mozilla.github.io/shield-studies-docs/study-process/
  • When should you use SHIELD over other options?

Uses Normandy, requires NO additional addon as long as a preference rides the release train

Survey mechanism, also run via Normandy

Pre-release only https://gecko.readthedocs.io/en/latest/browser/experiments/experiments/index.html

Custom builds of Firefox that are served to some percentage of the direct download population