  Alloy and TLA+ are two formal specification languages that are increasingly
popular due to their simplicity and flexibility, as well as the effectiveness
of their companion model checkers, the Alloy Analyzer and TLC, respectively.
Nonetheless, while TLA+ focuses on temporal properties, Alloy is better suited
to handle structural properties, requiring ad hoc mechanisms to reason about
temporal properties. Thus, both have limitations in the specification and
analysis of systems rich in both static and dynamic properties. This paper
explores the pros and cons of these two frameworks when handling this class of
systems through the step-by-step modeling, specification and verification of an
example.
