ARPradar: a network scanner built by a network engineer

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ARPradar is a free network scanner for Mac and Windows. Point it at a subnet and it lists every device with its IP and MAC address, maker, a readable name taken from DHCP, UPnP, SNMP, web page titles or Ubiquiti discovery, and a guess at what kind of device it is. Scans are saved per organisation, and it can draw a network map from a UniFi controller, with slow links marked in orange.

Its maker is a network engineer who can't write Swift or Rust, so Claude Code wrote the SwiftUI Mac app and a Tauri port with a Rust scan engine for Windows. The maker's part was knowing what a good scan looks like and saying when something was wrong. Claude ran the tests, waited for GitHub Actions builds and checked the interface against demo data before asking for a real test. When Windows builds kept failing, it traced the cause to GitHub's download servers timing out and stopped re-running builds until they recovered.

Claude couldn't see the maker's real network from its sandbox, so anything about the live LAN had to be tested by hand.