Ultimate Automizer
Ultimate Automizer is a free software model checker and a toolchain in the Ultimate program analysis framework.
What Ultimate Automizer is
Ultimate Automizer is a free software model checker and a toolchain in the Ultimate program analysis framework. The framework is intended to verify whether a C program satisfies a specified property, and its web interface lets users run C-program verification. Automizer's method is based on automata and uses the Ultimate Automata Library. It applies trace abstraction, extending proofs that individual traces cannot occur into Floyd-Hoare automata covering wider parts of a program. For concurrency, it uses an automata model based on Petri nets. The project provides regular Windows and Linux releases, and its archives include command-line versions. The documented command line takes an SV-COMP property file and either one C file or a C file with a matching GraphML witness. The listed input languages are C and Boogie, with web and on-premise deployment. The core and many plugins use LGPLv3 with a linking exception to Eclipse RCP and Eclipse CDT. The project reports overall SV-COMP wins in 2016, 2017, and 2023 through 2026.
Good
- Provides a web interface for verifying C programs.
- Command-line archives are available for Windows and Linux.
- Uses automata-based verification and trace abstraction.
- Free software with C and Boogie listed as inputs.
Watch out
- The web interface is described for C verification.
- No free trial is offered.
Who it suits
Ultimate Automizer is suited to developers, students, and researchers working on program verification, especially those analyzing C programs. The project also invites University of Freiburg students interested in contributing to contact an Ultimate developer.
Verdict
Ultimate Automizer offers both web-based C verification and command-line use through project archives. Its automata and trace-abstraction approach is aimed at program analysis, rather than general-purpose software use.
The facts
Each one read from Ultimate Automizer's own pages, with the date it was checked.
What it does
- Audience
- The project describes its developers as mostly students and researchers in the University of Freiburg software engineering group.checked 7 Oct 2026
- Award
- The site reports that Ultimate Automizer won the overall ranking at SV-COMP 2026.checked 7 Oct 2026
- Command line
- The available Automizer archives contain command-line versions that participated in the Competition on Software Verification.checked 7 Oct 2026
- Concurrency
- For concurrency, Automizer uses a Petri-net-based automata model.checked 7 Oct 2026
- Development
- The site says most Ultimate developers are students and researchers in Andreas Podelski’s software engineering group at the University of Freiburg.checked 7 Oct 2026
- Download
- The project says it provides regular releases for Windows and Linux.checked 7 Oct 2026
- Framework
- Ultimate is a program analysis framework whose toolchains can verify whether a C program fulfills a given specification.checked 7 Oct 2026
- Input
- The documented command-line interface accepts an SV-COMP property file and either one C file or a C file with a matching GraphML witness.checked 7 Oct 2026
- Integration
- Automizer is one toolchain within the Ultimate software analysis framework.checked 7 Oct 2026
- License
- The core of Ultimate and many plugins are licensed under LGPLv3 with a linking exception to Eclipse RCP and Eclipse CDT.checked 7 Oct 2026
- Maintainer
- Ultimate Automizer is maintained by Matthias Heizmann.checked 7 Oct 2026
- Method
- Automizer implements an approach based on automata and uses the Ultimate Automata Library.checked 7 Oct 2026
- Product
- Ultimate Automizer is a software model checker and one toolchain in the Ultimate software analysis framework.checked 7 Oct 2026
- Purpose
- Ultimate Automizer is a software model checker that implements an approach based on automata.checked 7 Oct 2026
- Recognition
- The Automizer page lists overall SV-COMP wins in 2016, 2017, and 2023 through 2026.checked 7 Oct 2026
- Security
- The official pages opened describe program verification and provide no security or compliance certification claims.checked 7 Oct 2026
- Support
- The Automizer page invites University of Freiburg students interested in contributing to contact Matthias Heizmann or another Ultimate developer.checked 7 Oct 2026
- Trace abstraction
- Automizer uses trace abstraction to generalize infeasibility proofs for individual program traces to Floyd-Hoare automata covering larger parts of a program.checked 7 Oct 2026
- Verification
- The web interface lets users verify C programs.checked 7 Oct 2026
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