I need a bot (or script) that refreshes the website page as quickly as possible and instantly clicks the button.

I need a bot (or script) that refreshes the website page as quickly as possible and instantly clicks the "Buy" button as soon as the product is available, all resolved to milliseconds.

Its only task is to add the product to the cart. No automatic filling of data or placing an order — I will do that manually.

Example: at 10:00 the product should appear, I start the bot at 9:58, and it begins refreshing the page until the buy button appears, and it clicks it, the product is added to the cart, and that’s where its job ends.

I need to minimize any delays or eliminate them altogether if possible.

I also need to be able to use it on 5 or sometimes more devices simultaneously to purchase the same product on the same website but from different accounts and devices.

The bot must work on laptops (Windows, macOS) and on phones (Android and iPhone).

What architecture do you see as the fastest:

local script in the browser (extension),

headless browser on a VPS NEXT TO THE STORE SERVER,

or a hybrid (local + service)?

Explain the advantages/disadvantages in terms of latency (response speed).

What specific steps do you take to minimize network latency (ping): server colocation, using WebSocket/SSE/Long-polling, TCP/UDP optimizations?

What are the minimum requirements for the internet connection (latency, speed)?

Do you use low-level methods (e.g., direct HTTP requests/simulating clicks on the backend) instead of emulating clicks in the UI — and what is safer in terms of compatibility with the site? Or does it send a direct request to the store server, because I understand that this is much faster?

How will the bot behave when the site is protected against bots (CAPTCHA, rate-limit, Cloudflare, bot-detection)? Are there suggestions for bypassing or legally operating under such conditions?

Are there special solutions needed for iPhone (due to iOS restrictions on background processes and browsers)? If so — which ones?

WHAT RISKS (ACCOUNT BAN, IP BLOCKS) AND HOW DO YOU MINIMIZE THEM (IP ROTATION, PROXIES, REQUEST FREQUENCY LIMITATIONS)?

Each of the 5 devices must be tied to a separate, persistent IP/proxy (do not change IP during the session). Please advise which proxies to use (residential/mobile/datacenter) and what measures you implement for automatic switching during blocks and for incident logging.

IMPORTANT: After clicking the "Buy" button on the NBU website, the product is not yet added to the cart until the "I am not a robot" confirmation (CAPTCHA / checkbox) is passed. The bot must track the appearance of this button and click it so that the product is actually added to the cart. Without this step, the addition to the cart will not occur.