CPAchecker vs Z3

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.

Z3 is a theorem prover and satisfiability modulo theories (SMT) solver used in software verification and analysis. SMT-LIB2 is its default input format, and it supports the SMT-LIB format. The project documents bindings or APIs for C, C++, .NET, Java, Go, OCaml, Python, Julia, and JavaScript/TypeScript. Z3 can be built with CMake, vcpkg, or Bazel, and the repository links to pre-built binaries for stable and nightly releases. A project wiki also links to a page for trying Z3 in a browser. It supports proof artifacts and counterexamples, and listed input languages include SMT-LIB2, Rust, Smalltalk, and several of the languages with documented APIs. Z3 is MIT licensed, with downloads and source code available at no charge. Python is required to build it; additional toolchains are needed for Java, .NET, OCaml, and Julia APIs. The README says MSVC builds enable Control Flow Guard and Address Space Layout Randomization by default.