Yeah Aniyoma is perfectly safe. Its just a rewrite of Tachiyoma, both Aniyoma and Tachiyoma have their source code publicly displayed as well.

Yes Aniyomi is safe to use.

You may also like saikou. It has fewer sources compared to aniyomi but it’s a good app, especially if you prefer to use anilist.

If you mean Tachiyomi, then yes, absolutely safe