OpenTofu

OpenTofu is the fork of Terraform taken at the last MPL 2.0 release, before HashiCorp's 2023 move to the Business Source License. Same HCL, same state model, same provider ecosystem; a module written for one reads for the other.

It sits in Adopt because the thing that made Terraform a safe default, an open license with no single company holding the terms, moved to OpenTofu and stayed there. The Linux Foundation governs it, MPL 2.0 covers every release with no four-year conversion clock, and no single vendor's acquisition or relicensing can change those terms unilaterally. That is the same bet the SOPS and mise placements are: a tool maintained under terms nobody can quietly revoke.

The fork has since earned Adopt on its own merits too, not just on the license it inherited. State encryption ships natively, without a wrapper script around terraform.tfstate. Provider and module authors iterate under a foundation instead of clearing changes with one company. Reaching for Terraform instead of OpenTofu needs a justification now, not the other way around.