Most of the TypeScript advice that actually holds up in production is boring: narrow your types at the boundary, prefer unions over booleans-that-should-have-been-enums, and let the compiler catch the mistakes you'd otherwise find in a code review.
Discriminated unions over optional fields
This blog's content blocks are a good example: instead of one Block type with a bunch of optional fields for every possible kind, each block is a tagged union — { type: 'paragraph'; text } | { type: 'heading'; text } | { type: 'quote'; text }. A switch on block.type gives exhaustive, type-checked rendering with no optional-field guesswork.
Typing animation variants instead of using 'any'
Animation helper functions are an easy place for 'any' to creep in, since the shape of a variants object can look arbitrary. Typing them against the animation library's own Variants type catches typos in transition properties at compile time instead of at runtime, when the animation just silently does nothing.
The compiler is the cheapest code reviewer you'll ever have — it just needs types precise enough to actually catch something.
Prefer narrow prop types over spreading everything
It's tempting to spread every prop from a data object into a component. Explicitly listing the props a component actually uses — even if it's more typing up front — makes it obvious at a glance what a component depends on, and stops unrelated data changes from silently changing component behavior.
