Csmith vs Mayhem

Csmith is a free, open-source generator of random C programs for finding compiler bugs through differential testing. Its output avoids undefined behavior and includes statistics for each generated program. A documented workflow compiles programs with GCC and Clang, then compares their outputs to identify differences. The tool can also create material for a C test suite when users do not want to write one themselves. Command-line options shown by csmith -h and csmith -hh customize random generation. Csmith runs locally on Linux and Windows. Ubuntu source builds require g++, CMake, and m4, followed by CMake and make; Windows builds are documented with Visual Studio or WSL. The project says it should build on most modern machines with a C++ compiler. Generated programs may loop indefinitely, so execution timeouts are recommended. The repository includes a COPYING license file. Bug reports and suggestions go through GitHub issues, with discussion on a mailing list; maintainers warn replies may be delayed.

Mayhem is a security platform for testing code and APIs and assessing software components in a dashboard. Its fuzzing combines AI-powered, network-aware methods with symbolic execution and triage. For code, it generates tests autonomously to find vulnerabilities and supplies a reproduction and backtrace for each defect. Mayhem for API tests for OWASP Top 10 API weaknesses and supports stateful, agentless testing. Dynamic SBOM reachability analysis helps identify which software components are on the attack surface. The platform produces vendor-neutral SARIF reports and real-time notifications, and lists integrations with tools including GitHub, Jenkins, GitLab, Jira, Slack, CircleCI, Azure DevOps, Google Chat and Travis CI. Deployment options include managed SaaS, private cloud and closed-network installation; command-line tools run on macOS, Linux and Windows. The Mayhem for API free plan allows up to 50 scans per month. Paid API plans cost $236 a month, with additional scans, enterprise features and personalized support; a 30-day trial is listed for paid plans.