Just use the one linked to from Nostrudel's relay management page.
What i found so far was this
https://github.com/mattn/algia written in go. I assume that with go installed, i can install this too. If you find something else you can inform me, i always like cli staff. Also another question. Is there a minimal relay for offline use with raspberry pi zero or even with termux? If you know...
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I'm using this with my raspberry pi zero 2 w.