This repository implements a threshold-based vertical autoscaling system for Proxmox VE virtual machines. It runs as a systemd service that periodically polls VM CPU and RAM usage via SSH commands (qm, pvesh) and adjusts CPU cores and RAM by 1 core or 512 MB when configurable high/low thresholds are crossed. The system includes host resource safety limits, per-VM threshold overrides, independent cooldowns for CPU and RAM, and optional billing tracking with CSV export and webhook notifications. It also provides a lightweight Prometheus metrics endpoint built on stdlib, supports Gotify and SMTP notifications, and offers a dry-run mode for safe evaluation. The architecture is a single-threaded polling loop with in-memory state, designed for simplicity and reliability rather than horizontal scaling or predictive analytics. The codebase is well-tested with over 290 unit tests and end-to-end tests against real Proxmox nodes, and includes comprehensive documentation via a VitePress site. Key reusable components include a generic SSH client with retry/backoff and host key policies, a thread-safe Prometheus metrics registry without external dependencies, and a configuration validation module that reports all errors at once.