Made a simple pulse / heartbeat monitor in Rust. It support monitoring Redis, MySQL, MariaDB and PostgreSQL databases.
Basically it is a middle man that will send a pulse / heartbeat to existing uptime monitor providers like BetterStack, UptimeRobot, HealthChecks..., as long as monitored services (Redis, MySQL, MariaDB, PostgreSQL) respond to simple SELECT 1 query and for Redis PING command.