Web server

Guide for understanding and configuring a Web server stack

The Web server stack is a language-agnostic container-hosting environment intended for serving web-facing containerized applications. Developers bring their own container image and seamlessly injects it into the Webscale hosting platform.

A Web server stack consists of:

Webscale Application
Webscale scaling cluster
Supporting infrastructure (VPC, routing tables, security group, etc.)

Network Topology

The stack can be deployed in two modes:

Standalone: Automatically provisions its own complete network tier, including VPC, Internet Gateway, and public routing tables.
Add-On: Seamlessly creates the auto-scaling web cluster in the existing infrastructure’s public subnets. When creating the web server stack, if an array of public subnets are provided, the web server will use the existing networking infrastructure and act as an add-on. See Configuration for details.

Variables

Variable Name	Type	Description
`size`	`string`	(Required) Plan size. Must be one of “dev”, “small”, “medium”, “large”, or “xlarge”.
`region`	`string`	(Required) The region to deploy the stack resources.
`public_subnets`	`list(string)` or `string`	Array of subnet IDs [primary, secondary]. May also be a reference to another stack’s output. If provided, the cluster will deploy into the existing network.

Example:

{
  {
    "type": "web-server",
    "environment": "/v2/environments/tu8aovkn7waj",
    "service": "/v2/services/2tpkjj7e0b28",
    "name": "PWA Frontend",
    "variables": {
      "size": "medium",
      "region": "us-east-1",
      "public_subnets": "/v2/stacks/4d4d1d4koe12/outputs/public_subnets"
    }
  }
}

Cluster Metadata Variables

Cluster metadata is used to configure container runtime variables. The following keys dictate how the container environment is constructed:

Metadata Key	Default	Description
`CONTAINER_IMAGE_URI`		(Required) The URI of the container image to pull and run.
`CONTAINER_HTTP_PORT`	`3000`	The internal port your containerized application listens on.
`CONTAINER_ENVIRONMENT`		A space-separated list of environment variables to forward into the container environment. Any variables specified here must also be defined as keys in the cluster metadata.

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Last modified on August 24, 2026