Free and open source Android apps by ByArchitect, each signed by its developer. Source code: https://github.com/by-architect

Currently it serves 3 apps. To add it to your F-Droid app, scan the QR code (click it to enlarge) or use this link:

https://fdroid.byarchitect.org/fdroid/repo

If you would like to manually verify the fingerprint (SHA-256) of the repository signing key, here it is:
50 94 1B DA C5 6B 05 6A 52 0A BF A3 FC 7D AA B7 89 DE E5 B8 3B 29 5D A5 4A 19 61 C7 BC 8A 91 C9