updo

Updo is a command‑line utility that continuously checks the availability and performance of web sites. It reports real‑time metrics such as uptime percentage, response latency, and SSL certificate expiration, and can issue alerts through desktop notifications or webhooks to services like Slack and Discord. The tool supports custom HTTP headers, various request methods, SSL verification options, and response assertions, allowing flexible health checks.

It can monitor many URLs at once, either from the command line or via configuration files, and can be deployed to 13 AWS Lambda regions for global coverage. Metrics can be exported to Prometheus and visualized in Grafana, and output is available as an interactive text UI, plain text, or structured JSON logs.

The project is distributed as a stable binary for macOS, Linux, and Windows, with package manager integrations and a quick‑install script. Source code is written in Go and released under the MIT license.