Beginning with the version 3 release of Fauna drivers, each release with a whole number is a new, stable feature release. Such releases include production-ready features and fixes from previous releases.

Bug fixes, or improvements that do not affect the behavior of Fauna queries, may be required from time to time, and may be driver-specific. For example, there might be a JavaScript 3.1 driver, and a Go 3.4 driver. Point releases are also considered stable, but typically do not introduce any new features.

Upcoming features are provided in preview releases, where the version is a higher whole number than the current stable release and has the -preview suffix. As preview releases contain in-development functionality (which may not work at all), preview releases should only be used for testing, or in non-production application environments. There is no guarantee that any feature in a preview release would remain unchanged for the next stable release.

Preview releases might occur with some regularity, but do not expect any particular schedule.

As of API version 3, each driver sends its API version to the Fauna server with each query. The server guarantees that each supported API version behaves as initially released. For example, if an existing function requires a behavior change in, say, the version 4 release, queries using version 3 drivers continue to execute with unchanged behavior.

For drivers older than API version 3 which do not specify their API version, the default API version is 2.12.

Over time, specific API versions may need to be deprecated. All functionality and behavior within an API version continues to function until the entire version has been deprecated and removed. We aim to provide deprecation notification for at least one year prior to removal of an API version. Known deprecations and their termination schedule are provided in the Deprecations section.