For my next product, I'm planning to set up a blog-like website (using hugo to make static pages that load fast). But I'd like for people to be able to enter their email somewhere so that I can easily notify them when there's another article.

I despise those services that spam everything with their own domain or click-jack your links. Instead, I feel like this should either let me manually email my contact list, or it should use my domain, my DKIM keys, etc.

I use mailgun for system emails. So is there any good newsletter service that has static-page forms and integrates with mailgun?