The server streams roughly 10 positions a second while the screen redraws at 60fps. Interpolation fills the gaps so cursors glide instead of teleporting between discrete points.
Give every user a color hashed from their ID, not assigned at random. The same person keeps the same color across sessions, so you can track identity from the corner of your eye.
An avatar stack with an overflow counter (three faces, then a +5) signals presence before anyone edits or speaks. You feel the room before you read a single name.
When someone selects an element, lock it and outline it in their color. Two people editing one shape is a corrupted shape, so the lock prevents the conflict before it can exist.
Follow mode binds your viewport to another user's: click their avatar and their pans and zooms drive your screen. It replaces a screen share for live design review.
Do / Don't
Do: Interpolate cursor positions between server ticks so movement reads as smooth motion at 60fps.
Do: Derive user color from a stable hash of the ID so it survives across sessions.
Do: Lock an element the instant it is selected and badge it in the editor's color.
Don't: Render cursors at the raw server tick rate, which makes them jump between points.
Don't: Assign colors randomly per session, which resets identity every time someone rejoins.
Don't: Allow two users to edit the same element at once.
The Design System Blueprint
An 11-page visual guide to consistent, scalable UI: colors, typography, spacing, components, motion.
