7 things I search for when I audit a TypeScript codebase:

any - Use a narrower type.

?. - Avoid by narrowing type.

?: - Optional properties are often overused/misused. Can often eliminate via a discriminated union.

string | number - Codebases often needlessly switch between number and string. Pick one. Narrow if possible.

= 0 - Zero is often misused to represent the explicit lack of a number instead of null.

let - Often a sign of needlessly complex mutative code.

as - Avoid type assertions. Not type safe. Zod often helps here.

Of course, this is far from an exhaustive list.

Interested in an audit? Ping me.

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