Run Triggers, Outputs, and Integrations

Scenario: An application workspace applies before the network workspace has published a compatible output.

Run triggers can queue downstream runs when an upstream workspace completes, while remote-state or output integrations share values. Dynamic provider credentials reduce standing secrets. VCS webhooks, notifications, run tasks, and APIs connect Terraform to review, security, cost, and deployment systems. Dependency automation does not solve compatibility: output contracts and staged releases still matter.

Analogy: A factory conveyor can move parts automatically, but the connector dimensions must still be versioned and compatible.

A worked configuration

# Upstream publishes a stable contract:
output "network_id" { value = fakecloud_network.shared.id }
# Downstream consumes only that contract.

Avoid long chains of automatically triggered applies that amplify one change across the estate. Make blast radius visible, support cancellation, and require stronger approval as changes approach production.

Note: Treat the plan as a change contract: understand every create, update, replacement, and destroy before approving it.

Goal: Reinforce this lesson in the tf-cross-state-outputs Terraform lab. Open /labs/terraform and choose slug tf-cross-state-outputs; the lab runs real Terraform against the offline FakeCloud provider.