Freddy Daniel

How it was built

1. 01Split the problem in two, because the two cases are not the same problem. For hosted platforms nothing needs to be streamed: every participant already has the source.
2. 02Hosted video is pure state sync. A shared link plus WebSocket events for play, pause, seek and volume, with the host as the source of truth. No media flows peer to peer at all.
3. 03Local video is a media problem. captureStream() on the video element produces a MediaStream, which is fed into a separate content peer connection alongside the existing camera track.
4. 04Keeping content on its own peer connection means video quality degradation never competes with the participants' camera and audio tracks.

How it was built

1. 01Built a calibration tool on top of a still frame from the camera, where a non-technical user draws polygon zones and labels them bed, chair or floor.
2. 02Used Fabric.js for the interaction layer: draggable vertices, live area feedback, snapping, and undo on a stack of canvas states.
3. 03Exported normalised zone coordinates as JSON so the geometry stays correct regardless of the resolution the model runs at.
4. 04Combined zone plus detected action into the alert rule, so the same detection produces different severity depending on where it happened.

How it was built

1. 01Profiled first. The bottleneck was not the network, it was Chart.js drawing tens of thousands of points into canvases only a few hundred pixels wide.
2. 02Applied decimation so the number of points drawn is bounded by the pixel width of the chart, not by the size of the dataset. Visually identical, dramatically cheaper.
3. 03Turned off entry animation on large series. Animating thirty thousand points is pure cost with no information gained.
4. 04Stopped blocking the page on the slowest widget: each chart resolves and paints independently rather than waiting on a single combined request.

How it was built

1. 01Kept a single codebase and moved everything customer-specific into build-time configuration: branding, icons, app identifiers, update endpoints.
2. 02Automated packaging so a new tenant is a config entry and a build, not a branch.
3. 03Used the desktop layer for what the browser could not do at the time, notably screen source selection and OS-level window handling.

How it was built

1. 01Customers were notified over WhatsApp. Four messages per token, at roughly ₹0.15 each, against shops serving 100 to 500 customers a day. The cost was survivable; the dependency was not.
2. 02The real risk was never the per-message price. It was that a single Meta policy change could take the product offline overnight, and I would have no way to reach a single customer.
3. 03Constraints made the usual answers unavailable: nothing can be installed on the customer's phone, and not every customer has a smartphone.
4. 04Current direction is to move the customer off messaging entirely, onto a shareable status link backed by web push, with an installable PWA as the primary channel and plain web as the fallback.
5. 05Wrote a phased resilience plan first: early warning, a permanent web QR entry point, a notification outbox, degraded mode, then SMS and spare numbers as the last resort.