CPAchecker vs SPIN

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.

SPIN is a free, self-hosted model-checking tool for analyzing the logical consistency of asynchronous systems, including distributed software and communication protocols. Systems are specified in Promela, which represents asynchronous processes, nondeterministic choices, loops, and local or global variables. Models can state correctness requirements, including linear temporal logic. SPIN supports interactive, guided, and random simulations of execution. For verification, it generates a C program for exhaustive or approximate checking of those requirements. Its product description lists detection of deadlocks, race conditions, incomplete specifications, and unjustified assumptions about process speeds. Partial order reduction optimizes verification runs, while the site provides guidance for multicore depth-first and breadth-first algorithms and swarm methods for large state spaces. SPIN runs on Linux, macOS, and Windows, as well as other listed systems. From version 6.4.5, its code, sources, and executables use the BSD 3-Clause license. Verification requires a working C compiler and preprocessor. The optional iSpin graphical interface is written in Tcl/Tk and requires Tcl/Tk.