The Evolution of Infrastructure as Code: From Scripting to Platform Engineering

Abstract

Infrastructure as Code (IaC) has transformed significantly since the late 1960s when it was first conceptualised. I have been fortunate enough to witness and benefit from this transformation personally throughout my career, from being a principal software engineer in 1993 to being an Enterprise Architect now.

Following is a brief history of how IaC has transformed through its various stages, mentioning the tools and methods that characterised contemporary infrastructure management. The focus of this post is to go through the history of IaC in four different eras: the Unix/Distributed Era (1960s–1990s), the Virtualisation Era (2000s), the Cloud Era (2010s), and the Platform as a Service (PaaS) & Internal Developer Platform (IDP) Era (late 2010s–today). With each passing era, it had game-changing tools and trends which shape up the world of infrastructure management nowadays. The article concludes with an analysis of future trends, including platform engineering, GitOps, and the rise of Kubernetes-native tooling.

1. Introduction

Infrastructure as Code (IaC) has revolutionised how organisations manage and provision IT infrastructure. By treating infrastructure configuration as code, IaC enables automation, reproducibility, and scalability. This article traces the evolution of IaC from its roots in the Unix era to the modern platform engineering landscape. I have identified key milestones, tools, and methodologies that have defined each era and discuss emerging trends that will shape the future of IaC.

2. The Unix/Distributed Era (1960s–1990s)

The foundation of IaC was laid during the Unix/Distributed Era, which introduced fundamental concepts of automation and scripting.

Key Milestones

1. UNIX (1969): The birth of modern operating systems, emphasising modularity and scripting. The UNIX operating system laid the groundwork for many concepts used in modern infrastructure.
2. Make (1976): One of the earliest build automation tools, introducing declarative workflows. A build automation tool, demonstrating early steps toward automating software construction and deployment.
3. Bourne Shell (1976): Enabled shell scripting for system automation. A command-line interpreter that enabled scripting and automation of tasks.
4. Bash (1989): Enhanced scripting capabilities with the "Bourne Again Shell." Bourne Again Shell, a more advanced command-line interpreter that further enhanced scripting capabilities.
5. Compaq Smart Start (1990s): Server configuration tool for Compaq hardware.
6. CFengine (1993): The first configuration management system, introducing desired state configuration. One of the earliest configuration management tools, automating system configuration. https://cfengine.com/
7. SUN JET (1994): Sun Java Enterprise Tools for server management.
8. PXE Boot 2 (1998): Facilitated network-based system deployment.

This era established the building blocks for automation, with tools like Make and CFengine paving the way for modern configuration management.

3. The Virtualisation Era (2000s)

The Virtualisation Era marked a shift toward managing virtualised infrastructure at scale.

Key Milestones

1. VMware (2002): Revolutionised enterprise computing with hardware virtualisation. Revolutionised server virtualisation, enabling multiple virtual machines on a single physical server. https://www.vmware.com/
2. Puppet (2005): Introduced infrastructure as code with version control and repeatability. An open-source configuration management tool for automating infrastructure provisioning and configuration. https://www.puppet.com/
3. Chef (2009): Advanced configuration management with reusable "recipes" and "cookbooks." Another configuration management tool focused on defining infrastructure as code using Ruby. https://www.chef.io/

Virtualisation and configuration management tools like Puppet and Chef enabled organisations to manage complex, distributed systems efficiently.

4. The Cloud Era (2010s)

The Cloud Era brought about a paradigm shift with the advent of cloud computing and containerisation.

Key Milestones

1. AWS CloudFormation (2011): Introduced infrastructure templating for cloud resources. Amazon's service for defining and provisioning AWS infrastructure as code. AWS CloudFormation
2. Ansible (2012): Simplified automation with an agentless architecture. An open-source automation tool that uses a simple, agentless architecture. Ansible
3. GitLab (2012): A web-based DevOps lifecycle tool that provides Git repository management, CI/CD, and more. GitLab
4. Terraform (2014): Offers cloud-agnostic infrastructure provisioning with a declarative syntax. HashiCorp's infrastructure-as-code tool that supports multiple cloud providers. Terraform
5. Kubernetes (2014): Revolutionised container orchestration.An open-source container orchestration platform for automating deployment, scaling, and management of containerised applications. Kubernetes
6. Microsoft Azure (2014): Expanded enterprise cloud capabilities.

Cloud-native tools like Terraform and Kubernetes enabled multi-cloud and hybrid infrastructure management, addressing the scalability and portability challenges of modern applications.

5. The PaaS & IDP Era (Late 2010s–Present)

The current era focuses on platform engineering, developer experience, and abstraction of infrastructure complexity.

Key Milestones

1. GitOps (2017): Introduced version control as the single source of truth for infrastructure.
2. Pulumi (2018): Enabled infrastructure definition using general-purpose programming languages. A modern infrastructure-as-code tool that allows using familiar programming languages to define infrastructure. Pulumi
3. Crossplane (2018): Control plane for managing infrastructure across cloud providers. https://www.crossplane.io/
4. AWS CDK (2019): Combined CloudFormation benefits with multi-language support. Cloud Development Kit, a framework for defining cloud infrastructure in code and provisioning it through CloudFormation. AWS CDK
5. Backstage (2020): Pioneered developer portals for platform engineering Backstage
6. Kratix (2021): Platform-as-a-Product framework for building internal platforms.
7. CNCF (2023): Cloud Native Computing Foundation's growing influence on IaC tools.
8. OpenTofu (2024): An open-source alternative to Terraform, emphasising community-driven innovation. OpenTofu

This era emphasises developer self-service, infrastructure abstraction, and platform-as-a-product approaches, enabling organisations to deliver value faster.

6. Future Trends

Looking ahead, I see the evolution of IaC continues to accelerate, with several emerging trends shaping its future.

1. Platform Engineering

Platform engineering focuses on building internal developer platforms (IDPs) that abstract infrastructure complexity and provide self-service capabilities. Tools like Backstage and Kratix exemplify this trend.

2. GitOps

GitOps, which uses Git as the single source of truth for infrastructure, is becoming the de facto standard for continuous delivery and deployment.

3. Kubernetes-Native Tooling

As Kubernetes adoption grows, tools like Crossplane and OpenTofu are enabling Kubernetes-native infrastructure management.

4. Infrastructure as Actual Code

Tools like Pulumi and AWS CDK are blurring the lines between infrastructure and application code, enabling developers to define infrastructure using familiar programming languages.

5. Open Source and Community-Driven Innovation

The rise of open-source projects like OpenTofu and the growing influence of the Cloud Native Computing Foundation (CNCF) highlight the importance of community-driven innovation in IaC.

7. Conclusion

The evolution of Infrastructure as Code reflects the overall trajectory of IT infrastructure management, from basic scripting to sophisticated platform engineering. Each stage built on the successes of the last, addressing new issues and leveraging technology advancements. Moving forward, platform engineering, GitOps, and Kubernetes-native tooling will continue to be the innovation drivers, enabling organizations to manage infrastructure more efficiently and deliver value earlier.

This journey not only reflects the technology revolution but also the cultural shift in IT—spotlighting collaboration, automation, and innovation at every stage