Good question — we'd be happy to submit a PR, but it's not clear to me that they'd be interested. Some background:

- Our approach writes new cache entries all the time. This can get expensive, and is a pretty big change in behavior from how actions/setup-go works today.

- actions/setup-go can basically be considered incredibly critical infrastructure for the public golang ecosystem. Any change in behavior is probably very risky and slow to happen. At this point I'd bet that we see no change, ever, in behavior.

Additionally there are a few relevant issues/prs that have been ignored for years so I'm not optimistic about contributing upstream. Frankly what we've done is write a very small bit of glue code that is likely most effective as a reference for teams writing their own custom caching actions that fit their exact needs:

- https://github.com/actions/setup-go/pull/426

- https://github.com/actions/setup-go/issues/630

- https://github.com/actions/setup-go/issues/395

- https://github.com/actions/setup-go/issues/596

That said we'd be happy if someone used our code and found it valuable! Lukas put a ton of effort into cleaning up my initial version, added the cache trimming, etc. We depend on this for all of our jobs and use it every day and think it's quite good.

actions/setup-go maintainer here! Great post, I like the ideas in there. We are always open to improvements, but it's true that low-risk ones are preferred. Feel free to submit your ideas to the GitHub issue tracker. I'll do some due diligence myself.