Maybe not, but you could show it to people whose context reveal that they might be interested – e.g. searching for "IDE" or "Elixir", reading about developer to

Maybe not, but you could show it to people whose context reveal that they might be interested – e.g. searching for "IDE" or "Elixir", reading about developer tools, etc. This is known as contextual advertising. Surveillance is not essential to internet advertising – in fact neither ROI, effectiveness or perceived relevance (when compared to all alternatives, including contextual advertising) has never been proven.