Good ol’ Prometheus and Grafana stack (Loki for logs, Tempo for traces) is perfect for smaller projects. You can also explore having OpenTelemetry collectors in the middle for more sophisticated processing and if you want to keep an eye on its ecosystem.

This is still the goto OSS stack, and I wouldn’t really recommend looking into smaller projects (usually backed by a single vendor) that are claiming better performance/lower resource usage for the same capabilities, because that always comes with a cost.

Logs: log files, logrotate and grep.

Metrics: Prometheus, Grafana and prometheus-client (Python library for Prometheus expoters).

Shynet is a good very light visitor tracking system for websites. Super simple.

Victoriametrics for metrics (7x ram reduction vs prom), Loki for logs but evaluating Victorialogs. Then grafana for ui. Cannot recommend vm enough, it’s fantastic.

logrotate, systemd, `journalctl -u server-name | grep whatever`