Giovambattista Fazioli

Posted on May 27

Netfox — The macOS app that never loses track of your network

#network #macos #utility #security

I built Netfox because every existing answer to "what's actually on my network?" annoyed me. The router admin page is a wall of MAC addresses. The vendor app shows three icons and a spinner. arp -a is a snapshot that forgets everything the second you close the terminal. I wanted something native, always-on, and honest — an app that watches the network continuously, keeps a history, and pings me when reality changes. So I made it.

Netfox has been a free public beta for a few weeks, and today it's launching on Product Hunt. This post is the tour: what it does, who it's for, and how to get it. It's still pre-1.0 — solid where it counts, with a clear roadmap for the rest — and it's free.

What is Netfox?

Netfox is a native macOS network monitor — five focused tools sharing one in-memory store, so a finding in one tool shows up wherever it matters.

It's not a packet sniffer (no privileged helper yet, by design) and it's not a firewall. It's the missing macOS app that answers three questions at a glance: what's on this network right now, when did each thing arrive, and is anything here doing something it shouldn't?

Where it sits next to the tools you already know:

vs. your router's admin page — Netfox merges Bonjour/mDNS, the system ARP cache, SSDP/UPnP, NetBIOS, and active ICMP probing. The router only shows you what the router happens to know; Netfox catches the quiet hosts, the casting boxes, the IoT junk.
vs. Fing and vendor apps — same idea, but native to macOS and built around a desktop workflow. No cloud account, no phone-first chrome, no upsell, no telemetry.
vs. nmap — Netfox doesn't replace it. nmap is for when you know what you're hunting. Netfox is for ambient awareness: leave it running, get pinged when something changes.

✨ Key features

Devices

Live device list — every machine on your network with hostname, MAC, IPv4/IPv6, vendor, and online state. Discovery runs five sources in parallel and merges them into one stream.
Per-device history — first seen, last seen, every online/offline transition, every IP/hostname/vendor change, on a timeline that survives across launches. "I'm sure that device wasn't here yesterday" finally has an answer.
Tagging — give any device a custom name and icon, so the cryptic "Espressif Inc." row becomes "Kitchen sensor".
Per-device mute — silence a noisy guest phone without hiding it from the list.

Security

Service Inventory — see the network grouped by the services it exposes (Plex, nginx, Telnet…), not just which ports are open where. Click a service to see every device contributing it.
Scan All Devices — one click probes every reachable host against a curated home-network port set (SSH, Telnet, RDP, VNC, SMB, HTTP, MQTT, MySQL/PostgreSQL/Redis…), and each device gets a risk badge.
Risk Inspector — every finding explained in plain English with a severity and a fix. No CVE wall of text.

Alerts

Five kinds, all opt-in, all de-duplicated: new device, returning after a long absence, risky new device, port opened on a known device, and new service identified. They land in an in-app inbox plus native macOS notifications, with a persistent log of everything that ever fired.

Wi-Fi and more

Wi-Fi diagnostics — every wireless network your Mac can see, with live signal-strength history, channel, band, and security mode.
Public IP + VPN awareness — your network's outward face at a glance, with a chip that lights up when the connection is tunnelled.
Demo Mode — one keystroke (⌘⇧D) masks device names, MAC suffixes, IPv6, Wi-Fi SSIDs/BSSIDs, and your public IP, so you can screenshot or screen-share without manually blurring half the frame. It's render-only — the underlying data is never touched, and turning it off restores everything instantly.

🛠 What's powering it

Netfox is Swift and SwiftUI, macOS 15+, with AppKit only where SwiftUI doesn't have an answer. State is @Observable end-to-end (no ObservableObject), and everything that touches the network runs on async/await and actors — the discovery providers, the port-probe queue, the SSDP socket, the HTTP service identifier — with per-host and global concurrency caps so it stays a polite neighbour on the LAN.

The reusable logic lives in a framework target (NetfoxCore: discovery providers, models, persistence, alert engine, security rules); the app target is just the UI. Each discovery backend (Bonjour, ARP, SSDP, NetBIOS, ICMP) is an independent provider behind a protocol, so adding a new one is dropping a file in and registering it. There's no privileged helper yet — everything in 0.3 runs as a normal user app; the helper arrives with bandwidth monitoring later on the roadmap.

📦 Install

Requirements

macOS 15 (Sequoia) or later
Apple Silicon or Intel Mac (universal binary)
A local network on Wi-Fi or Ethernet
The Wi-Fi tool needs Location permission (macOS gates SSID details behind it). Netfox asks once; the data never leaves your Mac, and the rest of the app works fine without granting it.

Download

Grab the latest DMG from the download page
Open the DMG and drag Netfox into Applications
Launch it — that's it.

The app is signed with Apple Developer ID and notarized by Apple, so Gatekeeper accepts it on first open. No right-click dance, no Terminal workarounds.

🔄 Auto-updates

Netfox checks for updates in the background and prompts you when a new build is available. Updates are signed end-to-end, so a hijacked feed can't slip you a malicious build. You can pause checks or switch to stable-only from Settings.

🗺 What's next

Wi-Fi diagnostics, expanded — channel scan, RSSI/SNR, channel recommendation
Link diagnostics — link speed, duplex, cable errors
Bandwidth monitor per device — the first feature that needs a privileged helper
Menu bar agent — network status at a glance without bringing the main window forward
1.0 — onboarding, localizations, polish

Feedback, stars, sponsorship

Netfox is launching on Product Hunt today, and three things genuinely help:

Download it and run it for a few days. The history view only gets interesting once the app has been watching for a while. Download the latest build.
Tell me what works and what doesn't — especially the Security tool's port set, which is opinionated and shaped by what people actually want flagged. Open an issue.
Upvote on Product Hunt or sponsor the work. Netfox is a solo project; an upvote on Product Hunt or a sponsorship is what keeps the release cadence going. A GitHub star helps too.

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