# Experimental features // :toc: // Set toclevels to be at least your hugo [markup.tableOfContents.endLevel] config key :toclevels: 4 == Description `--experimental` is a single global flag that gates several unrelated features. It is available on every subcommand, and it announces itself: [source,text] ---- Experimental Mode Enabled ---- [WARNING] ==== Experimental features can change or disappear without going through the deprecation cycle described on the link:/docs/help/deprecations/["Deprecations" page]. A pipeline that depends on one may need adjusting on any release, not only on a major one. ==== == What it enables === CUE manifests Without the flag, a `.cue` manifest is refused outright: [source,text] ---- cuelang support is experimental, please use '--experimental' flag to enable it ---- The flag also adds `updatecli.cue` to the filenames Updatecli looks for when no manifest is named on the command line. Ordinarily that search covers only `updatecli.yaml` and then the `updatecli.d` directory, so a `updatecli.cue` sitting in the working directory is not picked up unless the flag is set. === Reporting to Udash link:https://github.com/updatecli/udash[Udash] collects pipeline results for viewing over time. Without the flag, publishing is skipped **silently**, no warning, no error, and the run reports success. Configuring `UPDATECLI_UDASH_*` or running `updatecli udash login` is not enough on its own. With the flag, results are published under a section headed `Udash - Experimental`. `--disable-udash-report` switches it off again without dropping the rest of the flag. === WebAssembly autodiscovery plugins A crawler whose name ends in `.wasm` is loaded as an external WebAssembly plugin. Without the flag it is skipped with a warning naming the crawler: [source,text] ---- Skipping autodiscovery plugin "example.wasm" because experimental features are disabled ---- The rest of the autodiscovery run continues normally, so this is easy to miss in a long log. The built-in crawlers described on the link:/docs/core/autodiscovery/["Autodiscovery" page] are unaffected and need no flag. == Using it [source,shell] ---- updatecli pipeline diff --experimental updatecli compose diff --experimental ---- This website's own CI runs `updatecli compose diff --experimental` on every pull request, so the flag is safe to adopt for regular use, the caveat is about stability of the features themselves, not about the flag being dangerous. TIP: Nothing already working changes when you add the flag. Enabling it never *disables* a stable feature, so adding it to a CI job that does not use any of the above is a no-op. == Go Further * link:/docs/help/deprecations/[Deprecations] - the stability promise that experimental features are exempt from. * link:/docs/help/environment/[Environment variables] - including the Udash variables. * link:/docs/core/autodiscovery/[Autodiscovery] - the built-in crawlers. * link:/docs/commands/[Commands] - the full flag reference.