SignalBar

SignalBar is a macOS menu bar app that continuously answers:

Is the network actually bad right now — and if so, which part is failing?

It focuses on diagnosis by layer, not a generic score:

1. Link
2. DNS
3. Internet
4. Quality

If your core path is healthy but a watched service is not, SignalBar keeps the core bars healthy and surfaces that as a service-specific issue instead of lying about the entire internet being broken.

Warning

SignalBar is still an early public prototype. The core architecture and test coverage are solid, but packaging, broader settings UX, and persistent history are still evolving.

Why SignalBar exists

A lot of network tools tell you that something is “slow” without telling you where the problem actually is.

SignalBar is designed for moments like:

• SSH or Zoom feels laggy
• a page refuses to load
• Wi‑Fi looks connected but everything feels weird
• one work service is down while the broader internet is fine

The goal is to make the menu bar answer three questions at a glance:

1. is the problem real?
2. is it local or upstream?
3. which layer is failing first?

Current capabilities

SignalBar currently includes:

• a runnable macOS menu bar app
• live NWPathMonitor link monitoring
• live DNS probes against default control targets
• live HTTPS probes against default control targets
• derived quality signals from latency, jitter, and reliability
• rolling in-memory history graphs
• two toolbar display modes
• two toolbar color modes
• launch at login from Settings… -> General
• a dedicated settings window for display, watched-target, and app-level preferences
• focused tests for diagnosis, aggregation, history, store behavior, and UI mapping

How to build and run

Requirements

• macOS 14+
• Xcode 16.1+ or a compatible Swift 6.1+ toolchain

Validate the repository

swift build
swift test
./scripts/lint.sh

Run the menu bar app

./run-menubar.sh

Stop the app

./stop-menubar.sh

Repository guide

• Getting started
• Development
• Architecture
• Privacy
• Project status
• Releasing

Privacy posture

SignalBar is designed to stay lightweight and local-first:

• no telemetry
• no packet capture
• no privileged monitoring
• no invasive permissions
• watched-target probing is opt-in
• current history is in-memory only

See docs/privacy.md for the exact behavior and current limitations.

Roadmap themes

Near-term work includes:

• richer target configuration UX and additional settings beyond the first dedicated settings window
• stronger packaging/distribution ergonomics
• persistent history storage
• continued diagnosis and scheduler refinement

See docs/status.md for the public project status.

License

MIT — see LICENSE.