--- title: Disabled Features sort_rank: 10 --- # Disabled Features Here is a list of features that are disabled by default since they are breaking changes or are considered experimental. Their behaviour can change in future releases which will be communicated via the [release changelog](https://github.com/prometheus/prometheus/blob/main/CHANGELOG.md). You can enable them using the `--enable-feature` flag with a comma separated list of features. They may be enabled by default in future versions. ## `@` Modifier in PromQL `--enable-feature=promql-at-modifier` The `@` modifier lets you specify the evaluation time for instant vector selectors, range vector selectors, and subqueries. More details can be found [here](querying/basics.md#modifier). ## Negative offset in PromQL This negative offset is disabled by default since it breaks the invariant that PromQL does not look ahead of the evaluation time for samples. `--enable-feature=promql-negative-offset` In contrast to the positive offset modifier, the negative offset modifier lets one shift a vector selector into the future. An example in which one may want to use a negative offset is reviewing past data and making temporal comparisons with more recent data. More details can be found [here](querying/basics.md#offset-modifier). ## Remote Write Receiver `--enable-feature=remote-write-receiver` The remote write receiver allows Prometheus to accept remote write requests from other Prometheus servers. More details can be found [here](storage.md#overview).