# Catch3 documentation Catch3 combines the upstream Catch2-compatible runner and API with Progmasoft's C++20 extensions. Start with the [tutorial](tutorial.md#top), then read [what Catch3 adds](progmasoft-catch3.md), [native property testing](progmasoft-properties.md), [the roadmap](progmasoft-roadmap.md) and [why the two API families remain distinct](why-catch3.md). The compatibility pages below retain real `catch2/` include paths, `Catch2::` CMake targets, and upstream version history; renaming those would make examples incorrect. The Progmasoft extension API lives under `Progmasoft/Catch3/...` and the `Progmasoft::Catch3` namespace. Its built library is separate from the upstream-compatible engine. The compatibility pages are about the bundled engine, not a claim that Catch3 is an official Catch2 release. ## Reference **Writing tests:** * [Assertion macros](assertions.md#top) * [Matchers (asserting complex properties)](matchers.md#top) * [Comparing floating point numbers](comparing-floating-point-numbers.md#top) * [Logging macros](logging.md#top) * [Test cases and sections](test-cases-and-sections.md#top) * [Test fixtures](test-fixtures.md#top) * [Explicitly skipping, passing, and failing tests at runtime](skipping-passing-failing.md#top) * [Reporters (output customization)](reporters.md#top) * [Event Listeners](event-listeners.md#top) * [Data Generators (value parameterized tests)](generators.md#top) * [Other macros](other-macros.md#top) * [Micro benchmarking](benchmarks.md#top) **Fine tuning:** * [Supplying your own main()](own-main.md#top) * [Compile-time configuration](configuration.md#top) * [String Conversions](tostring.md#top) **Running:** * [Command line reference](command-line.md#top) * [Running specific section/generator](filtering-execution-path.md#top) **Odds and ends:** * [Frequently Asked Questions (FAQ)](faq.md#top) * [Best practices and other tips](usage-tips.md#top) * [CMake integration](cmake-integration.md#top) * [Tooling integration (CI, test runners, other)](ci-and-misc.md#top) * [Known limitations](limitations.md#top) * [Thread safety of the compatibility engine](thread-safety.md#top) **Other:** * [Why the Catch2 compatibility base?](why-catch.md#top) * [Migrating from v2 to v3](migrate-v2-to-v3.md#top) * [Historical Catch2 open-source users](opensource-users.md#top) * [Historical Catch2 commercial users](commercial-users.md#top) * [Upstream contribution guide (historical)](contributing.md#top) * [Upstream release notes (historical)](release-notes.md#top) * [Upstream deprecations (historical)](deprecations.md#top)