A visitor forms an impression of your company before they read a word. Not from the logo — from whether the page responded. Latency is the first brand signal you send, and it is sent on a mid-range phone on a poor connection, not on the machine the site was built on.
The budget has to exist before the design
Performance work added at the end of a project is triage. You are removing things people already approved. Set the budget first — a total transfer size, a target for interaction latency, a device and network profile — and it becomes a design constraint like any other. Constraints improve design. Deadlines do not.
Ambition and speed are not opposed
This site runs a real-time WebGL scene. It also ships a static, fully readable document that renders before any of it initialises. The 3D layer is lazily mounted, resolution-capped, paused when off-screen and skipped entirely when the device or the user's motion preference says no.
- Render the words on the server. Everything else is enhancement.
- Load the heavy layer after first paint, never before it.
- Cap device pixel ratio. Most of the cost of a canvas is resolution nobody perceives.
- Stop animating what is not on screen. An idle tab should cost nothing.
If the experience only works on the machine it was built on, it does not work.
Measure on the hardware your customers own
Lab scores on a fast laptop are a comforting fiction. Field data from real sessions is the only number worth reporting to a leadership team, and it is usually the one nobody has. Instrument it before the redesign, so the next argument about a hero video can be settled with evidence.