Pietrust FAQ

The Product: General

Q: What's it good for?


Q: Is the PieTrust reputation system commercially available today?

A: The PieTrust system is ready to be used today in small communities via email. In addition, we have completed a prototype web application and are now working to turn it into a robust, highly-available web service. The prototype includes an implementation of a collusion-resistant reputation algorithm, an API to access the system, and an optional frontend which users can use to give evaluations and view scores. Contact us if you would like to use the system over email, or if you would like to be added to the waiting list to alpha-test our web application.

The Product: more detail

Q: What if someone creates a million fake user accounts and rates themselves highly? Can they take all of the reputation ("PieShare")?

A: If the users' pie charts were simply averaged together, or used like votes, then this would be a problem. But the way that Pietrust calculates PieShare is carefully designed to ensure that the system cannot be gamed in this way. The fake accounts will only receive reputation in proportion to how highly they are rated by other users in good standing.

Q: Does the seed group get more reputation? Do they decide how much reputation everyone else gets?

A: No; for most purposes, they are on the same footing as the other group members. Their role is as a tie-breaker. Technically, they do have a little more influence, but not much; or at least, not much unless they choose to game the system in a way that is clearly visible to the rest of the community.

Q: Can people see each others' evaluation?

A: Yes, all evaluations are public, to promote accountability. In the future, we may add an option to have private evaluations. Please email us if you would like this feature.

Q: What if someone is a valuable contributor but an inflammatory personality? We want to reward this person well for their work, but we don't want them to determine how much everyone else gets.

A: By default, each user gives each other user a single evaluation; optionally, any person can choose to give any other person two evaluations; how much that person should be paid, and how much influence that person should have over others. This is more complicated, but it allows these two considerations to be separated. This feature is not yet implemented.

Q: I'd like more detail, please

A: Contact us if you'd like technical details on how the system works.

The Project

Q: Can I join the project?

A: Yes, email us below. PieTrust itself is an open project using our own system to evaluate participants. The source code will be available on github, however although it is free for personal and non-commerical use, the current version of the code is not licensed as open-source. However, we will relicense each old version to the the Apache license three years after it is checked into our repo.

Q: How much does it cost?

A: Pietrust is free to our invited alpha-testers during alpha testing. After launch, our plan (which we may revise) is to provide a freemium tier for small groups, and to charge a per-seat subscription fee for larger groups.

Contact us

To get in touch with us, email:

Copyright 2009-2015 Pietrust. "Pietrust" and "Pieshare" are our trademarks.