6.3. Infrastructure as Code

Infrastructure as Code (IaC) means configuring cloud services and infrastructure using code, rather than manually pointing and clicking in a web console.

The configuration lives in version-controlled code, right alongside the application or model code it supports.

This makes your infrastructure repeatable, auditable, and automated.

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Why use IaC?

• Consistency – ensure every environment (dev, test, prod) is set up identically.
• Automation – spin up or tear down infrastructure with a single command.
• Speed – new environments for models, APIs, or experiments can be created in minutes.
• Versioning – infrastructure changes are tracked in Git, just like application code.
• Collaboration – analysts and engineers can share the same definitions for how systems should run.

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Example in Pricing

A pricing team wants to deploy a new LightGBM model into production:

• With IaC, the cloud resources (compute instance, container registry, storage, networking) are defined in code.
• The same code can create a test environment for validation, and later a production environment for live deployment.
• If more compute power is needed for a large impact analysis, the configuration file can be updated and reapplied - no manual reconfiguration required.

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Terraform

Terraform is one of the most popular IaC tools. It uses configuration files (.tf) to define infrastructure in a cloud-agnostic way.

You declare what you want (e.g. a container, function, or database), and Terraform figures out how to build it.

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Example Terraform File

# Define the provider (Azure in this case)
provider "azurerm" {
  features {}
}

# Resource group for pricing models
resource "azurerm_resource_group" "pricing" {
  name     = "pricing-rg"
  location = "UK South"
}

# Container instance to run our model API
resource "azurerm_container_group" "pricing_model" {
  name                = "pricing-model-api"
  location            = azurerm_resource_group.pricing.location
  resource_group_name = azurerm_resource_group.pricing.name
  os_type             = "Linux"

  container {
    name   = "model"
    image  = "myregistry.azurecr.io/pricing-model:latest"
    cpu    = "2"
    memory = "4"

    ports {
      port     = 8080
      protocol = "TCP"
    }
  }

  ip_address {
    type = "Public"
    ports {
      port     = 8080
      protocol = "TCP"
    }
  }
}