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IntroductionCustom container images Custom containersPrivate registriesGPUs and other resources GPU accelerationReserving CPU and memoryScaling out Scaling outDicts and queuesJob processingConcurrent inputs on a single container (beta)Secrets and environment variables SecretsEnvironment variablesDeployment Managing deploymentsInvoke deployed functionsContinuous deploymentScheduling and cron jobsWeb endpoints Web endpointsStreaming endpointsWeb endpoint URLsRequest timeoutsTunnels (beta)Data sharing and storage Passing local dataVolumesMounting local files and directoriesStoring model weightsCloud bucket mounts (Beta)Network file systems (superseded)Dynamic sandboxes (beta)Reliability and robustness Failures and retriesPreemptionTimeoutsTroubleshootingSecurity and privacyIntegrations Connecting Modal to your Vercel accountOkta SSOOther topics File and project structureDeveloping and debuggingCold start performanceMemory Snapshot (beta)Modal user account setupWorkspacesEnvironmentsJupyter notebooksAsynchronous API usageGlobal variablesContainer lifecycle and parametersApps, Stubs, and entrypoints

Environment variables

Runtime environment variables

The Modal runtime sets several environment variables during initialization. The keys for these environment variables are reserved and cannot be overridden by your function configuration.

The following variables provide information about the function runtime environment:

  • MODAL_IS_REMOTE - Set to ‘1’ to indicate that the function is running in a remote container.
  • MODAL_CLOUD_PROVIDER — Modal executes functions across a number of cloud providers (AWS, GCP, OCI). This variable specifies which cloud provider the Modal function is running within.
  • MODAL_ENVIRONMENT — The name of the Modal Environment the function is running within.
  • MODAL_IMAGE_ID — The ID of the modal.Image used by the Modal Function.
  • MODAL_REGION — This will correspond to a geographic area identifier from the cloud provider associated with the function (see above). For AWS, the identifier is a “region”. For GCP it is a “zone”, and for OCI it is an “availability domain”. Example values are us-east-1 (AWS), us-central1 (GCP), us-ashburn-1 (OCI).
  • MODAL_TASK_ID — The ID of the container running the Modal Function.

Container image environment variables

Container image layers used by a Modal function’s modal.Image will set environment variables which will be present within your function’s runtime environment. For example, the debian_slim image sets the GPG_KEY variable.

To override image variables or set new ones, use the .env method provided by modal.Image.