Alloy Analyzer vs CPAchecker

Alloy Analyzer is a free model-checking tool for describing systems in the Alloy language and exploring the structures those descriptions permit. It searches for structures that satisfy constraints and for counterexamples to properties. Models can represent collections of structures that change over time, including security configurations and switching network topologies. The Analyzer presents results graphically, with appearance options that can be tailored to a domain. Alloy 6 adds mutable state, temporal logic, and temporal model checking; that checking requires NuSMV or nuXmv to be installed and available in PATH. The self-contained executable includes the Pardinus/Kodkod model finder, SAT solvers, the standard Alloy library, tutorial examples, and source code. The same JAR can be used as an API in other applications. Sterling adds a web-based visualizer with graph and table views, customizable and extendable with JavaScript. Alloy is self-hosted, supports Linux, macOS, Windows, and API use, and is maintained by volunteers.

CPAchecker is a configurable software verification tool based on configurable program analysis concepts. It accepts C and SV-LIB inputs, lists predicate analysis for SV-LIB programs, and supports invariants, counterexamples, and proof artifacts. It can also validate termination witnesses in YAML formats 2.1 and 1.0. The project lists a hybrid verification method and provides a self-hosted deployment. CPAchecker is free software under the Apache 2.0 License. Version 4.2.2, released in December 2025, is available as Unix and Windows ZIP archives; Debian and Ubuntu users can install it from the SoSy-Lab APT repository, and a Docker image is available. Java 21 or later is required as of version 4.2. An older version, 1.6.1, can be accessed through a web interface, where some functions are unavailable in the restricted environment. Documentation includes installation instructions, tutorials, and getting-started guidance. Installation questions, bug reports, and suggestions can go to the users mailing list or issue tracker. The project is based in Munich, Germany.