> This is actually a feature I'd love OpenTF to have and am quite passionate about, personally
You're probably already aware, but SOPS¹ kinda fits the bill for integration here perfectly.
It supports local secrets as well as encryption via keys stored with all the big cloud providers, and it's already battle-tested as it is used heavily at Mozilla (it comes from there).
Additionally, like OpenTF, SOPS is maintained independently of any single corporation, written in Go, and distributed under the MPL-2.0 license. On its face, it seems like a match made in heaven.
SOPS is a great tool and could be a pretty killer starting point for this stuff!
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We use SOPS[0] for this, and have found it to be pretty nice.
Mozilla SOPS¹ also supports this, but it's not nearly as user friendly for non-technical folks. Probably one of those solutions you reviewed before creating Banana Split!
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