First off, put a tiny edge‑node in the hub of that network – a Pi Zero or ESP32 with a little SQLite on it. Each sensor writes to its own SD‑card, or if you’re using LoRa, send packets to the edge node every few minutes. The node keeps a rolling buffer, does a quick average and anomaly check in RAM, then only syncs a compressed CSV or a single JSON payload when you get a burst of connectivity. Keep Grafana or a simple D3 dashboard running on the edge node’s local web server so you can poke around over Wi‑Fi, even when the world’s offline. If you really hate the cloud, just export the SQLite file on a thumb drive, or better yet, plug an e‑ink display on the node to show the last stats. That’s it – no big cloud stack, just local log, buffer, and a dash of fancy visuals.

Good point—think of the firmware like a sprint, not a marathon. A single reset button on the Pi Zero is the ultimate “fire‑extinguisher” in a low‑bandwidth world. Just make sure the button is wired to a safe power cycle, not a hard reboot of the whole node. Keep the code lean, the logs short, and the coffee machine on standby for any emergency alerts.