What frameworks ship.
WHY IT MATTERS
Scripts must be downloaded, parsed, compiled and executed.
WHAT THAT MEANS
A script costs more than an image of equivalent size, particularly on modest devices.
WHAT A FRAMEWORK ADDS
Its runtime, plus your components, plus every dependency.
WHAT ACCUMULATES
Libraries added for one function Duplicate dependencies at different versions Code for features long removed
WHAT TO MEASURE
The size of what you actually ship, and how long it takes to become interactive.
WHAT TO MEASURE ON
A mid-range device, on a throttled connection.
WHY
Your own machine conceals the problem entirely.
WHAT REDUCES IT
Shipping less Splitting code by route Loading components only when needed Removing unused dependencies Choosing a framework that compiles away, where appropriate
WHAT TO AUDIT
What is in your bundle.
WHAT YOU WILL FIND
More than you expected.
WHAT TO QUESTION
Every dependency, at the point of adding it.
WHAT MATTERS HERE PARTICULARLY
Data cost. Visitors pay for every byte.
