Infrastructure as Code vs. Configuration as Code: What's the Difference?

Infrastructure as Code and Configuration as Code get used almost interchangeably in casual conversation, and it's easy to see why: both involve writing code instead of clicking through a console, both live in version control, both are core DevOps practices. But they solve different problems, sit at different layers of the stack, and mixing them up leads to real confusion when choosing tools or designing a pipeline.

Here's where the line actually falls, and why it matters more than it might seem.

The Short Answer

Infrastructure as Code (IaC) provisions and manages the underlying resources: servers, networks, databases, load balancers. Configuration as Code (CaC) sets up and manages what runs on top of that infrastructure once it exists: installed packages, application settings, feature flags, environment variables.

Put simply: IaC builds the thing. CaC configures the thing once it's built. In a well-run pipeline, they run sequentially, not interchangeably: IaC provisions an empty virtual machine, and CaC bootstraps it into a working server.

What Infrastructure as Code (IaC) Actually Does

IaC treats physical and virtual infrastructure the same way software engineers treat application code: as something you write, version, test, and deploy through a repeatable process, not something you click together by hand in a cloud console.

What IaC Manages

IaC operates at the hardware and virtualization layer. Typical responsibilities include:

• Virtual machines: defining instances with specific CPU, RAM, and storage constraints
• Networking: scripting firewalls, subnets, gateways, and load balancers
• Managed services: spinning up a managed database instance or a Kubernetes cluster

The output of an IaC run is infrastructure that exists: a VM is running, a subnet is created, a cluster is provisioned. But that infrastructure is typically still bare. It doesn't yet have your application installed, your configuration files in place, or your services running.

Popular IaC Tools

Terraform is the most widely used tool in this category, alongside OpenTofu (its open-source fork) and cloud-native options like AWS CloudFormation. These tools generally work in a declarative style: you describe the desired end state of your infrastructure, and the tool figures out how to get there.

What Configuration as Code (CaC) Actually Does

CaC, often used interchangeably with the broader term Configuration Management, picks up where IaC leaves off. It deals with what happens inside a piece of infrastructure once it exists, making sure the software running on it stays consistent, correctly configured, and doesn't drift out of its intended state over time.

What CaC Manages

CaC operates at the operating system and application layer. Typical responsibilities include:

• OS settings: opening internal system ports, adjusting registry or system-level configuration
• Package deployments: ensuring the right runtime versions, web servers, and security patches are installed
• Application properties: managing environment variables, API keys, and feature flag settings across dev, staging, and production

Where IaC answers "does this server exist," CaC answers "is this server actually set up the way it's supposed to be."

Popular CaC Tools

Ansible, Puppet, Chef, and SaltStack are the standard tools here. Most use an agent-based or agentless model to apply and continuously enforce a desired configuration state across a fleet of machines, catching and correcting drift when a system's actual state diverges from what it's supposed to be.

IaC vs. CaC: Side-by-Side Comparison

	Infrastructure as Code (IaC)	Configuration as Code (CaC)
Primary goal	Create, modify, and destroy infrastructure	Set up and maintain system/application state
Layer	Hardware, virtualization, network	Operating system and application
Key actions	Provisioning a VM, creating a VPC subnet	Installing packages, updating config files, managing feature flags
Popular tools	Terraform, OpenTofu, AWS CloudFormation	Ansible, Puppet, Chef, SaltStack

How IaC and CaC Work Together in a Deployment Pipeline

In practice, these aren't competing approaches; they're sequential stages of the same pipeline. A typical flow looks like:

• IaC runs first, provisioning the raw infrastructure: an empty virtual machine, a network, a managed database shell.
• CaC runs immediately after, bootstrapping that infrastructure into something usable: installing dependencies, applying configuration, and starting the application.

Skipping either step leaves a gap. IaC alone gets you infrastructure with nothing running on it. CaC alone has nothing to configure until the infrastructure exists. Mature DevOps pipelines treat both as essential, connected phases rather than alternative choices.

Common Points of Confusion

Is IaC Part of CI/CD?

Yes, typically as one of the earlier stages. IaC provisioning usually runs as part of a CI/CD pipeline's deployment phase, often gated behind approval steps for production environments, since infrastructure changes can have wide-reaching effects.

Are IaC and Terraform the Same Thing?

No. Terraform is one implementation of the IaC pattern, not the pattern itself. IaC is the practice; Terraform, OpenTofu, and CloudFormation are tools that implement it, each with different syntax and cloud-provider relationships.

Where Configuration Management Tools Fit

Configuration Management is the broader discipline that Configuration as Code implements. Some tools blur the boundary, since certain configuration management platforms include limited infrastructure-provisioning capability alongside their core configuration features, but the conceptual split above still holds: one layer is about what exists, the other is about how it's set up.

Beyond Servers: Applying CaC Principles to SaaS Platform Configuration

Most discussions of IaC and CaC assume a traditional infrastructure stack: VMs, containers, cloud networking. But the underlying idea behind Configuration as Code, treating configuration as versioned, testable, auditable code rather than manual changes, applies just as well to platforms that don't hand you servers at all.

Modern SaaS platforms, particularly complex ones like CCaaS (Contact Center as a Service) platforms, have deep, consequential configuration layers of their own: routing rules, integrations, permission structures, workflow logic. There's no VM to provision because the infrastructure is already managed by the vendor, but the configuration on top of it behaves exactly like the problem CaC was built to solve: it drifts, it changes without a clear record, and a bad change is hard to trace back to its source.

This is the space InProd operates in specifically for Genesys Cloud and Genesys Engage contact centers: applying CaC-style discipline (version control, environment promotion, drift detection, audit trails) to a SaaS platform's configuration layer, where traditional IaC tools like Terraform have no infrastructure to provision and traditional CaC tools like Ansible have no servers to configure. It's the same underlying philosophy, extended to a layer most IaC/CaC tooling was never built to reach.

FAQ

What is the difference between IaaS and IaC?

IaaS (Infrastructure as a Service) is a cloud computing model: a vendor like AWS or Azure providing virtualized infrastructure over the internet. IaC (Infrastructure as Code) is a practice for provisioning and managing that infrastructure through code rather than manual configuration. IaC is often used to provision resources within an IaaS platform, but the two terms describe different things: one is a delivery model, the other is a management practice.

Is IaC considered DevOps?

Yes. IaC is one of the foundational practices of DevOps, applying software development principles (version control, automated testing, code review) to infrastructure management. It supports the broader DevOps goals of faster, more reliable, more repeatable deployments.

Is IaC part of CI/CD?

Generally yes. IaC provisioning commonly runs as an automated stage within a CI/CD pipeline, particularly for spinning up or updating environments as part of a deployment process.

Book a call to see how InProd brings CaC-style version control, environment promotion, and audit trails to Genesys Cloud configuration.