No blank import in library

Blank import in main

No dot imports

Image type in own file

Metadata type in own file

File order: constants before types

File order: constructor before methods

Unexported internal fields

%q in error messages

Unexported helpers

range over index loop

range n for counting

%q in parse errors

if-init scope for errors

No naked return in long funcs

Early return on parse error

Unexported helpers

Map initialized not nil

strings.Builder for report

strconv not fmt for int conversion

slices package for sorting

lo for filter operation

lo for group-by operation

lo for chunk/paginate

Generics not any

maps package usage

No reflect usage

Initialized empty collections

SortByPrice non-mutating

Capacity hint on output slice