EXPERIMENTS:

Experiments are only enabled in alpha releases of Terraform CLI. The following features are not yet available in stable releases.

- The experimental "deferred actions" feature, enabled by passing the `-allow-deferral` option to `terraform plan`, permits `count` and `for_each` arguments in `module`, `resource`, and `data` blocks to have unknown values and allows providers to react more flexibly to unknown values.
- `terraform test cleanup`: The experimental `test cleanup` command. In experimental builds of Terraform, a manifest file and state files for each failed cleanup operation during test operations are saved within the `.terraform` local directory. The `test cleanup` command will attempt to clean up the local state files left behind automatically, without requiring manual intervention.
- `terraform test`: `backend` blocks and `skip_cleanup` attributes:
  - Test authors can now specify `backend` blocks within `run` blocks in Terraform Test files. Run blocks with `backend` blocks will load state from the specified backend instead of starting from empty state on every execution. This allows test authors to keep long-running test infrastructure alive between test operations, saving time during regular test operations.
  - Test authors can now specify `skip_cleanup` attributes within test files and within run blocks. The `skip_cleanup` attribute tells `terraform test` not to clean up state files produced by run blocks with this attribute set to true. The state files for affected run blocks will be written to disk within the `.terraform` directory, where they can then be cleaned up manually using the also experimental `terraform test cleanup` command.

## Previous Releases

For information on prior major and minor releases, refer to their changelogs: