This started after reading this thread and wondering: what if an ESP8266 behaved less like a single Arduino sketch and more like a tiny persistent UNIX box? https://news.ycombinator.com/item?id=47851630
KernelESP gives the ESP8266 a serial shell, LittleFS filesystem, scripts, pipes, cron, timers, relays, sensor rules, backups, diagnostics, JSON API, web UI, and SMTP email alerts. It is persistent across reboots: config, scripts, relays, rules, cron jobs, profiles, logs, web assets, and help files live in LittleFS.