Triggers allows you to execute code during deployment of CDK apps. They are very useful to implement "self tests" or populate initial data. If a trigger fails, deployment fails.

Usage:

```ts
new Trigger(this, 'VerifySomething', {
  dependencies: [ scopes... ],
  handler: lambdaFunction
});
```

This is a productization of https://github.com/cdklabs/cdk-triggers.