Suriyakumarvijayanayagam
81e2c605b9
The first launch was a code box with a link under it, then an empty Live screen with 'No cameras' in amber in a far corner, then a form asking for an IP address, and for the first few minutes of all of it the engine silently downloading 275 MB with nothing on screen but a stopped-looking status. Walked in a browser with the new mock; nobody who was not an installer would have got through it. Now: a welcome that asks the one question a shop owner can answer - managed from a head office, or on this PC only - with each path in a sentence; a Getting Started checklist on Live that reads its three steps from the engine and ticks them itself (recognition ready, camera added and connected, camera proven by a walk-past), with the one button for the next step, and that disappears the moment somebody is recognised; and the model download reported as a percentage in the tray, the sidebar and the checklist, parsed by the supervisor from the engine's own progress lines. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01KGcjxF1cNLcuwc3DAPcnfj
Behavision agent (Go)
The half of the edge install that touches the network. The Python engine keeps the cameras and the models; this keeps the tray icon, the UI shell, the MQTT connection and the offline queue.
┌─ agent (Go) ───────────────────┐ ┌─ engine (Python) ────────┐
│ tray icon + WebView2 window │ │ RTSP capture │
│ supervises the engine process │───────▶│ YuNet / ArcFace / FAISS │
│ MQTT publish + offline spool │◀───────│ SQLite (biometric) │
│ S3 handoff, tenant config │ local │ localhost API + events │
└────────────────────────────────┘ HTTP └──────────────────────────┘
Why the split
Go cannot run ONNX, OpenCV or FAISS, so the engine stays Python and ships frozen. Go is here for what it is actually better at: a durable queue that survives a store's internet dropping, a supervised child process, and one language shared with the server so the MQTT contract has a single definition.
Why not a Windows service
A service runs in session 0 and cannot draw a tray icon — that is Windows session isolation, not a library limitation. Since the product is "user starts and stops it from the tray", the agent is a normal user-session process that spawns the engine as a child. That also means it never needs elevation at runtime: starting a child process does not, controlling a service does.
internal/engine is written so a service wrapper can be added later without
touching the supervision logic.
Layout
main.go entry point, mode dispatch
internal/engine start/stop/supervise the Python engine, health polling
internal/spool durable event queue (survives restart and outage)
internal/mqtt broker client, publishes from the spool
internal/config tenant identity, broker settings, credentials
frontend/ React UI served into the WebView
Build
go build ./... # agent alone
wails build # agent + frontend, once the UI is added