Tools: How I Built a 1 GB Observability Stack for My Go Startup Using Prometheus, Loki, and Grafana

I needed observability for my Go Telegram bot running on a free VPS with only 4 GB of RAM, where the app already used ~2 GB. After comparing tools by RAM usage, I chose Prometheus (metrics), Loki (logs), Promtail (log collector), and Grafana (dashboards) — the entire stack fits in ~1 GB. The article covers structured logging with slog, exposing metrics via promauto, Docker Compose configs with memory limits, Loki/Promtail/Prometheus setup, and building Grafana dashboards stored as JSON in the repo.