Satori has no account, no sync, and no telemetry. Here is where your data is kept, and what leaves the Mac.
Satori has no account. It does not sync your history, tabs, or bookmarks to a server, and it sends no telemetry.
Your history, open tabs, bookmarks, downloads, and hidden elements are files under ~/Library/Application Support/Satori/. They are encrypted with AES-GCM, under a key that Satori keeps in your login keychain. They are protected from other apps and other macOS accounts, and Settings, site icons, extensions, and the data websites store (cookies, caches) are not encrypted by Satori. Your passwords live in the same keychain, as internet passwords labeled Satori.
Some things do leave the Mac: the pages you ask for, their icons, and update checks. The full list is on the Privacy page, with the reason for each item.
Satori is small, fast, and quiet, with one field for addresses and searches.
Download Satori for Mac.
Satori is signed with a Developer ID certificate and notarized by Apple. macOS may ask you to confirm the first time you open it, but there is no malware or unidentified-developer warning. Updates arrive on their own through Sparkle.