Can I deactivate checks during deployments?

Yes. The cleanest way to handle deploys is to wrap them in a maintenance window, which tells Oh Dear "don't alert on failures during this period".

There are three ways to create one:

• In the app: open the monitor's settings and add a maintenance window manually. Good for one-off planned work.
• Through the API: perfect for wrapping your deploy script. Start a window before the deploy, stop it after.
• On a recurring schedule: if your deploys always happen at the same time, set up a repeating maintenance window once and forget about it.

While a maintenance window is active, failed uptime checks are recorded but don't count against your uptime percentage and don't trigger notifications. The second your deploy finishes, end the window and we're back to watching things normally.

Full walkthrough with examples: maintenance windows documentation.