jsonfile:

Use jsonfile to persist a Go value to a JSON file.

type JSONFile
    func Load[Data any](path string) (*JSONFile[Data], error)
    func New[Data any](path string) (*JSONFile[Data], error)
    func (p *JSONFile[Data]) Read(fn func(data *Data))
    func (p *JSONFile[Data]) Write(fn func(*Data) error) error

There is a bit more thought put into the few lines of code in this repository than you might expect. If you want more details, see the blog post.