Universal Interaction

Fides is designed from the ground up to be a universal interaction language.

Relation with process calculi

Although Fides is not a calculus, it shares some key features with process calculi:

• Execution corresponds to code modification, according to the semantics. This implies that any runtime state can be represented by code in a straightforward manner. It also implies that code is ephemeral by default; it disappears after being executed.
• Concurrency is achieved simply via parallel composition.
• Communication happens via channels and message passing.

Principled unbounded metaprogramming

Unbounded metaprogramming allows processes to write arbitrary Fides code programmatically at runtime, while ensuring that no illegal code can be written. The latter is achieved via a faithful representation of Fides within Fides as typeful values.

Universal trusted third party

A designated channel allows communication with the Launcher, which provides certified code launch as a service. Given a piece of Fides code that defines a process behavior, the Launcher starts a process with the given behavior, and returns a signed launch certificate for the given code.

This makes the Launcher a universal trusted third party, as well as a personification of Fides.

Code

This Github project is a work-in-progress implementation of Fides in Scala.