I am building a service that continuously checks a visa-appointment portal and confirms slots the instant they open. The job is to architect and code the entire automation workflow—from session management and scheduling logic to resilient, cloud-hosted execution—so it can run 24/7 without being detected or throttled. You must already operate at an expert level with large-scale automation; theoretical knowledge is not enough. Anti-bot security is my top concern, so your portfolio should include live, bypass-resistant systems that still function today under heavy scrutiny. Direct, verifiable references or screen-share walk-throughs of those projects will be required before we proceed. The project hinges on Cloudflare Turnstile integration. Whether you solve it through token generation, browserless challenges, or a hybrid farm of headless browsers is up to you, but the final design must slot seamlessly into the rest of the pipeline and survive future Turnstile updates. Core expectations • Highly concurrent backend (Python, Node, Go, or comparable) able to scale horizontally without single-point failures • Smart queueing and retry logic so no slot is wasted while avoiding brute-force patterns • Clean, well-documented code, containerised for simple deployment (Docker/Kubernetes preferred) • Real-time metrics and alerting to verify success rates and spot blocks early Acceptance criteria 1. System books at least 95 % of available slots in a controlled test window. 2. Turnstile challenge handling remains stable over 72 h of nonstop traffic. 3. Zero critical errors under a simulated peak of 10 000 concurrent requests. If you can demonstrate proven, production-ready experience that matches the above, let’s talk.