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Cal.com on Cloud Run — Lab Guide

📖 Configuration Guide

Overview​

Estimated time: 45–90 minutes

Cal.com is an open-source scheduling platform — the self-hosted Calendly alternative — built with Next.js and Prisma on PostgreSQL. This lab takes you through the full operational lifecycle of the Cal.com on Cloud Run module on Google Cloud: deploy it, access and verify it, run it day-to-day, observe it, diagnose common problems, and tear it down.

The lab focuses on operating the Cloud Run module and the Google Cloud platform, not on Cal.com product features. For the complete list of provisioned services and every configuration input (organised by group), see the Configuration Guide — this lab deliberately does not duplicate that detail so it stays accurate over time.

Objectives​

By the end of this lab you will be able to:

  • Deploy the module from the RAD platform and locate the resources it provisions.
  • Access and verify the running service and complete Cal.com's onboarding.
  • Perform day-2 operations — inspect, scale, update, and manage secrets and backups.
  • Observe the service with Cloud Logging and Cloud Monitoring.
  • Diagnose and resolve the most common deployment and runtime issues.
  • Tear the deployment down cleanly.

Prerequisites​

  • Services_GCP deployed in the target project (provides the VPC, Cloud SQL, Artifact Registry, and shared service accounts this module depends on).
  • A Google Cloud project with billing enabled.
  • gcloud CLI authenticated: gcloud auth login and gcloud auth application-default login.
  • Project Owner (or equivalent) IAM on the project.
  • RAD platform access with permission to deploy modules into the project.

Set these shell variables once; every task below reuses them:

export PROJECT="<your-gcp-project-id>"
export REGION="us-central1"          # the region you deploy into

Task 1 — Deploy the module [Automated]​

  1. Click Deploy in the RAD platform top navigation, open Cal.com (Cloud Run) from the Platform Modules list to start configuration, set project_id, and review the inputs. Configure only what you need — the Configuration Guide documents every input by group, with defaults. Review the estimated cost (if credits are enabled) and click Deploy, which opens the deployment status page with real-time logs.

  2. The platform provisions the Cloud Run service (Next.js on port 3000), a Cloud SQL (PostgreSQL 15) database with its Secret Manager secrets (DB password plus auto-generated NEXTAUTH_SECRET and CALENDSO_ENCRYPTION_KEY), mirrors the Cal.com image into Artifact Registry, and runs a one-shot database-initialisation job that creates the empty database and role. No GCS bucket is created — Cal.com keeps all state in PostgreSQL. First deploys take roughly 20–35 minutes (Cloud SQL creation dominates).

  3. When it completes, discover the resources with name-agnostic filters (so the commands keep working regardless of the deployment suffix):

    SERVICE=$(gcloud run services list --project="$PROJECT" --region="$REGION" \
      --filter="metadata.name~calcom" --format="value(metadata.name)" --limit=1)
    SERVICE_URL=$(gcloud run services describe "$SERVICE" \
      --project="$PROJECT" --region="$REGION" --format="value(status.url)")
    echo "Service: $SERVICE"
    echo "URL:     $SERVICE_URL"

Task 2 — Access & verify [Manual]​

  1. Confirm the service is healthy. Cal.com's health path is /, which returns HTTP 200 once the app has finished running its Prisma migrations on first boot — the schema is created on boot, not by the init job, so allow several minutes on a fresh deploy (the startup probe window is ~8 minutes for exactly this reason):

    curl -s -o /dev/null -w "%{http_code}\n" "$SERVICE_URL/"

  2. Open $SERVICE_URL in a browser and complete Cal.com's onboarding to create the initial administrator/owner account, then connect at least one calendar. Immediate hardening note: self-hosted Cal.com allows self-service sign-up by default — restrict it (or front the service with IAP) if the instance should not be public. The database password can be retrieved if needed:

    DB_SECRET=$(gcloud secrets list --project="$PROJECT" \
      --filter="name~calcom" --format="value(name)" --limit=1)
    gcloud secrets versions access latest --secret="$DB_SECRET" --project="$PROJECT"

  3. Note the URL discipline: NEXT_PUBLIC_WEBAPP_URL / NEXTAUTH_URL default to the deterministic run.app URL. Before sharing booking links on a custom domain, set webapp_url — the public URL is baked into every booking and OAuth link.

Task 3 — Operate & keep it running (Day-2) [Manual]​

  1. Inspect the service and its revisions (each deploy creates an immutable revision; traffic shifts to the newest healthy one):

    gcloud run services describe "$SERVICE" --project="$PROJECT" --region="$REGION"
    gcloud run revisions list --service="$SERVICE" --project="$PROJECT" --region="$REGION"

  2. Scale by changing the min/max instance inputs and clicking Update on the deployment details page — the module owns the service spec, so scaling is a configuration change, not a manual gcloud edit (a manual edit would be reverted on the next apply). The default is scale-to-zero (min = 0, max = 1, request-based billing); set min_instance_count = 1 if cold starts bother your bookers.

  3. Update the application version by changing the version input via Update on the deployment details page; the new image tag is mirrored and a new revision rolls out, applying any pending Prisma migrations on its first boot.

  4. Manage secrets and jobs — and know which secrets are immutable:

    gcloud secrets list --project="$PROJECT" --filter="name~calcom"
    gcloud run jobs list --project="$PROJECT" --region="$REGION"   # db-init job

    CALENDSO_ENCRYPTION_KEY encrypts stored calendar/OAuth credentials and NEXTAUTH_SECRET signs sessions — never rotate either after first boot outside a planned maintenance window (rotation orphans every connected calendar or logs out every user, respectively).

  5. Open a database session for inspection or maintenance:

    INSTANCE=$(gcloud sql instances list --project="$PROJECT" --format="value(name)" --limit=1)
    gcloud sql connect "$INSTANCE" --user=calcom --project="$PROJECT"

Task 4 — Observe: Logging & Monitoring [Manual]​

  1. Logs — from the CLI or the Logs Explorer:

    gcloud run services logs read "$SERVICE" --project="$PROJECT" --region="$REGION" --limit=50

    Logs Explorer filter: resource.type="cloud_run_revision" AND resource.labels.service_name="<service>".

  2. Monitoring — open the Cloud Run dashboard for the service and review request count, request latency (P50/P95/P99), instance count (scaling behaviour, including scale-to-zero periods), and CPU / memory utilisation. The module also provisions an uptime check against /; confirm it is green under Monitoring → Uptime checks, and review Alerting → Policies.

Task 5 — Troubleshoot & debug [Manual]​

Durable techniques for the failure modes you are most likely to hit. These are platform-level diagnostics and do not change with Cal.com releases.

  • Revision unhealthy / service won't serve: Cal.com runs prisma migrate deploy on every start, and the startup probe allows roughly 8 minutes for first-boot migrations. Inspect the latest revision and its logs before concluding the service has failed: 
    gcloud run revisions list --service="$SERVICE" --project="$PROJECT" --region="$REGION"
    gcloud run services logs read "$SERVICE" --project="$PROJECT" --region="$REGION" --limit=100
  • OOM crash at startup: memory_limit must be ≥ 2 GiB — Next.js 16 OOM-crashes below it and the revision never becomes Ready.
  • Database connection errors: confirm the Cloud SQL (PostgreSQL 15) instance is RUNNABLE, the DB password secret exists, and enable_cloudsql_volume = true — direct private-IP TCP fails Prisma's certificate verification against Cloud SQL's CA; the Auth Proxy socket is required.
  • Initialisation job failed: list executions and read the failed one's logs: 
    gcloud run jobs executions list --job="${SERVICE}-db-init" \
      --project="$PROJECT" --region="$REGION"
  • Server refuses to boot / URL errors: Cal.com validates its public URL at startup. Verify webapp_url (or the injected default) is a real URL — the image's localhost:3000 default is rejected.
  • 403 / permission errors: verify the runtime service account's IAM roles; if IAP is enabled, remember it blocks all unauthenticated requests — including public booking pages and embeds.

See the Configuration Guide's Configuration Pitfalls section for setting-specific gotchas.

Task 6 — Tear down [Automated]​

On the Deployments page, open the deployment and click the Trash icon (Delete). Delete runs terraform destroy and is irreversible (the deployment record is retained for history). If a deployment is stuck and the RAD platform can no longer manage it (for example after manual changes that conflict with the Terraform state), use Purge instead — it removes the deployment from RAD's records without destroying the cloud resources (it makes RAD forget the project). This removes everything the module created — the Cloud Run service, Cloud SQL database (all users, event types, and bookings), Secret Manager secrets (including NEXTAUTH_SECRET and CALENDSO_ENCRYPTION_KEY), and Artifact Registry images. Resources owned by Services_GCP (the VPC, shared Cloud SQL, registry) are managed separately and are not removed here.

Summary​

TaskTypeOutcome
1 — DeployAutomatedModule provisions Cloud Run, Cloud SQL (PostgreSQL 15), secrets, mirrors the image, and runs DB init
2 — Access & verifyManualHealth check passes; complete onboarding, restrict open sign-up, set webapp_url
3 — OperateManualInspect revisions, scale, update version, respect immutable secrets, DB access
4 — ObserveManualQuery Cloud Logging; review Cloud Monitoring metrics and uptime check
5 — TroubleshootManualDiagnose revision, OOM, database, init-job, URL-validation, and IAM issues
6 — Tear downAutomatedDelete (Trash) removes all module resources

By · Google Cloud certified: ACE · PCA · PCD · PDE · PSE · CDL

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