Troupe

Formalization

Troupe’s information-flow guarantees are the subject of an ongoing formalization in Lean 4. Dated snapshots make the model, security condition, and proofs available as the development progresses.

Scope

The current formalization models a single process executing Troupe’s intermediate representation under an information-flow monitor, with mailbox inputs and outputs. It establishes a knowledge-based security condition with separate bounds for downgrades.

The model has no thread creation or scheduler. The result concerns the modeled single-process semantics; it does not establish correctness of the full concurrent and distributed runtime or of the compiler.

The online report is transcribed from the Lean development using an LLM. The Lean development is the source of truth; the report connects definitions and lemmas to their Lean declarations.

Snapshots

Each snapshot records a particular state of the development. New snapshots will be listed here, with earlier versions retained at their dated URLs.