nginx_webp

location ~* ^(/.+)\.(jpg|jpeg|jpe|png|gif)$ {
    add_header Vary Accept;

    if ($http_accept ~* "webp"){
        set $imwebp A;
    }
    if (-f $request_filename.webp) {
        set $imwebp  "${imwebp}B";
    }
    if ($imwebp = AB) {
        rewrite ^(.*) $1.webp final;
    }
}