import reflex as rx

Deploy to GCP Cloud Run

The reflex cloud deploy --gcp command deploys a Reflex app to your own Google Cloud Run service.

The CLI fetches a Cloud Run-ready Dockerfile and deploy script, then submits the build through Cloud Build. Google Cloud stores the image in Artifact Registry and runs it on Cloud Run. The temporary deployment files do not modify your project tree.

# Enterprise tier only
Self-deploying to GCP Cloud Run is part of the **Enterprise tier** of Reflex Cloud. Contact [[email protected]](mailto:[email protected]) to upgrade.

# Self-service vs. managed GCP deploys

This page covers the **self-service** `reflex cloud deploy --gcp` command, which builds and deploys from your own machine using your local `gcloud`. If you'd rather connect a GCP account to your organization once and deploy with the normal `reflex deploy` command — keeping the managed lifecycle (history, rollback, scaling, logs) — see [Cloud Providers](/docs/hosting/cloud-providers/).

Prerequisites

Before running the command, install and authenticate the local tools the deploy script invokes:

• gcloud — install from the Google Cloud SDK docs, then run:
  • gcloud auth login
  • gcloud auth application-default login
• docker — required by gcloud builds submit for source upload.
• bash — used to run the deploy script.

You also need:

• A GCP project with billing enabled. Without it, gcloud services enable fails with UREQ_PROJECT_BILLING_NOT_FOUND.
• An Enterprise-tier Reflex Cloud subscription and a logged-in Reflex CLI (reflex login).

Quick start

From the root of your Reflex app:

reflex cloud deploy --gcp \
    --gcp-project my-gcp-project-id \
    --service-name my-reflex-app

The CLI will:

1. Authenticate with Reflex Cloud and fetch the deployment files.
2. Create a temporary cloudbuild.yaml.
3. Print the commands for review.
4. Ask for confirmation, then enable the required APIs, create the Artifact Registry repository, build the image, and deploy the Cloud Run service.
5. Delete the temporary file.

An existing Dockerfile in --source remains unchanged and is not used by this workflow.

When it's done, you'll get a service URL like https://my-reflex-app-<project-number>.us-central1.run.app.

Options

What gets created in your GCP project

The deploy script enables these APIs (if not already enabled):

• cloudbuild.googleapis.com
• run.googleapis.com
• artifactregistry.googleapis.com

It then creates (idempotently) and uses:

• An Artifact Registry Docker repository at ${REGION}-docker.pkg.dev/${GCP_PROJECT}/${AR_REPO}.
• A Cloud Build job that builds and pushes the image.
• A Cloud Run service named ${SERVICE_NAME}, deployed with --allow-unauthenticated, port 8080, 1 vCPU, 1 GiB memory, --min-instances 1, and --session-affinity.

Re-running the command pushes a new image tag and rolls the Cloud Run service forward.

How the build runs

The generated cloudbuild.yaml is a single Cloud Build step that:

1. Writes the Dockerfile into the build workspace via a single-quoted heredoc:
   yamlCopy

   - |
     cat > Dockerfile <<'REFLEX_DOCKERFILE_EOF'
     FROM python:3.13-slim
     ...
     REFLEX_DOCKERFILE_EOF
     docker build -t "$_IMAGE" .
     docker push "$_IMAGE"
   

2. Builds and pushes the image, tagging it with _IMAGE (passed to gcloud builds submit as --substitutions=_IMAGE=...).

Because Cloud Build runs its own substitution pass over args, every literal $ in the Dockerfile is doubled to $$ before embedding (e.g. ENV PATH="${UV_PROJECT_ENVIRONMENT}/bin:$PATH" becomes ENV PATH="$${UV_PROJECT_ENVIRONMENT}/bin:$$PATH" in the YAML). Cloud Build's parser converts $$ back to $ before bash runs, so the Dockerfile written into the workspace contains the original characters.

Security model

The CLI runs the deploy script under a restricted environment. Only an explicit allowlist of host variables is forwarded to bash — things like PATH, HOME, CLOUDSDK_*, DOCKER_*, and proxy/TLS variables. Unrelated host secrets such as AWS_*, GITHUB_TOKEN, or arbitrary user variables are not forwarded, so a tampered or compromised manifest cannot exfiltrate them.

You can preview the rewritten script, generated cloudbuild.yaml, and Dockerfile before anything runs by using --dry-run:

reflex cloud deploy --gcp \
    --gcp-project my-gcp-project-id \
    --dry-run

Non-interactive use (CI)

For automated pipelines, pass --no-interactive and an explicit --token:

reflex cloud deploy --gcp \
    --gcp-project "$GCP_PROJECT_ID" \
    --service-name my-reflex-app \
    --token "$REFLEX_TOKEN" \
    --no-interactive

In non-interactive mode the CLI will not prompt, and it will exit non-zero if a token cannot be resolved.

Troubleshooting

Reflex denied the request (403). GCP Cloud Run deploys require an Enterprise tier subscription. Your account is not on the Enterprise tier. Contact [email protected].

Billing must be enabled for activation of service(s) ... (UREQ_PROJECT_BILLING_NOT_FOUND) Attach a billing account to the GCP project, or use a different --gcp-project.

The value of '--project' flag was set to Project number. To use this command, set it to PROJECT ID instead. Pass the project ID (e.g. my-app-123456), not the numeric project number.

No active GCP account found. Run gcloud auth login and gcloud auth application-default login.

The 'gcloud' / 'docker' / 'bash' CLI was not found on PATH. Install the missing tool and ensure it's on PATH for the shell you're invoking the CLI from.

Dockerfile content contains the reserved heredoc marker 'REFLEX_DOCKERFILE_EOF'. Vanishingly unlikely — the Dockerfile from Reflex Cloud happens to contain a line that exactly matches the heredoc terminator the CLI uses to embed it. Re-run after the next CLI release, or open an issue.

Couldn't find 'gcloud builds submit' in the deploy script. The CLI rewrites the gcloud builds submit block in the Reflex-supplied deploy script to use --config=. If Reflex Cloud changes the shape of that script before the CLI is updated to match, you'll see this error — upgrade reflex-hosting-cli (uv tool upgrade reflex-hosting-cli or pip install -U reflex-hosting-cli).