Core Architecture

Naive coordinate broadcasting costs the square of the crowd — everyone talks to everyone. StreetWizard attacks that cost by sending less, not by routing differently.

• [+] PRESENCE / STREAM SPLITRiders share one realtime channel. Heavy identity — avatar, plate, build — is published once through presence. The position stream carries only what changes, so a 5 kB avatar never rides the hot path.
• [+] ADAPTIVE EMISSIONThe send rate follows fleet size: a convoy of twelve emits about twice a second for tight formation; past two hundred it backs off to once every four seconds, where the difference is imperceptible anyway.
• [+] CLIENT-SIDE PREDICTIONEach client fills the gaps itself, extrapolating a peer's motion from its last position, heading and speed. The map reads smoother than the network actually is, and rendering is capped at the sixty nearest vehicles — a thousand pins is a dead phone, not a feature.

Hardened since this page was first written: km and level are no longer client-writable at all, and every write passes a server-side velocity clamp.

A community distance counter is only worth showing if it cannot be gamed. The design question is not how to aggregate fast, but who is allowed to assert a number.

• [+] MEASURED ON DEVICEThe client derives its own distance from the GPS trail, filtering the jitter a parked phone produces so a car standing still never accumulates kilometres.
• [+] BANKED PER RIDEREach rider owns one row and only ever advances their own. There is no shared counter to contend over, so there is no race to resolve.
• [+] AGGREGATED SERVER-SIDEThe community figure is a single privileged aggregate over those rows. Because no client ever submits the total, no client can inflate it — the number on screen is the sum of what was actually driven.

Streaming the exact same track to a convoy requires mitigating network latency variance between peers.

• [+] SERVER-HELD START TIMEThe station keeps the current track and the instant it started on the server, not on any one device. There is no host to elect and nothing to renegotiate when someone drops.
• [+] SEEK ON JOINA client works out how long the track has been playing and seeks straight to that offset. Everyone converges on the same position in the same song — close enough that a convoy hears one track, without pretending network jitter does not exist.

The frontend relies on a heavily customized WebGL rendering pipeline.

• [+] CAMERA INTERPOLATIONA single requestAnimationFrame loop drives position, bearing and zoom with dt-aware exponential smoothing. Cockpit pitch sits at 66° and zoom eases from 18.2 at rest toward 16.8 at speed, so the view opens up as the car goes faster.
• [+] SPATIAL UI LAYERSAvatars, reports and pins are HTML markers positioned over the canvas, not WebGL layers — deliberately. It keeps them stylable, accessible and tappable, and the marker count is capped so the DOM never becomes the bottleneck.

A debugging mechanism built into the client, so a field crash arrives with enough context to reproduce it.

• [+] STATE SNAPSHOTA caught error boundary serializes what is needed to reproduce the failure: the failing view, the active route state and the current peer list.
• [+] RECENT GPS TRAILThe snapshot ships with the last stretch of raw GPS, because a navigation bug is rarely reproducible without the path that triggered it.
• [+] ROUTED TO THE DESKReports are routable to lead@seub.net, so a production crash reaches engineering while the drive it came from is still fresh.

Broadcasting live audio to thousands of concurrent pilots would normally generate catastrophic egress costs. StreetWizard offloads it entirely.

• [+] STATE-ONLY BROADCASTRealtime channels never carry audio. They broadcast the playback state payload only — the exact started_at timestamp.
• [+] CLIENT-SIDE SYNCEach device computes (now - started_at) and pulls the static chunk from the Edge CDN with an aggressive cacheControl of 31536000, pushing bandwidth to localized nodes.
• [+] GAPLESS PG_CRON ROTATIONA PostgreSQL pg_cron job triggers wizardops.radio_rotate() to keep the station alive, gapless and advancing even with zero active listeners.

Trigger-based counters and REPLICA IDENTITY FULL are real. Street Cred is not: it lives in localStorage on one device, not in SQL. Proximity gating on Wiper Notes is not enforced at the database layer either — `fleet_notes` has no path-crossing check.

Live social state at map scale dies on naive queries. The data layer is tuned for constant-cost reads and reflow-free pushes.

• [+] TRIGGER-BASED COUNTERSHeavy COUNT() queries are eliminated via SQL triggers maintaining denormalized counters — Street Cred math resolves as (Likes / (Likes + Dislikes)) * 100 server-side.
• [+] REPLICA IDENTITY FULLWebSocket change feeds ship complete row images so clients patch state surgically, pushing live updates without forcing DOM reflows.
• [+] PROXIMITY GATINGWiper Notes delivery is enforced at the database layer: a message row is only readable when a verified physical path-crossing exists between the two pilots.