Ansible vs Pulumi: What are the differences?

Introduction

Ansible and Pulumi are both automation tools used in software development and infrastructure management. However, they have key differences that set them apart from each other.

1. Execution Model: Ansible operates on a push-based execution model, where the control machine pushes the configurations and instructions to target machines. On the other hand, Pulumi uses a pull-based execution model, where the infrastructure resources are continuously monitored for changes and updates are automatically applied to ensure the desired state.

2. Language Support: Ansible is primarily based on YAML, which provides a simple and human-readable syntax for defining tasks and configurations. In contrast, Pulumi supports multiple programming languages such as Python, JavaScript, TypeScript, and Go, allowing developers to express infrastructure as code using their preferred language.

3. Cloud Provider Integration: Ansible has support for a wide range of cloud providers, enabling developers to manage and provision resources across different cloud environments. Whereas Pulumi takes a multi-cloud approach and allows developers to define infrastructure resources using a unified API that transparently supports multiple cloud providers, making it easier to deploy and manage applications across diverse cloud environments.

4. Resource Lifecycle Management: Ansible utilizes idempotent tasks to ensure that the desired state is achieved on target machines. It focuses on executing tasks only when required and performs automatic cleanup of any unwanted changes. Pulumi, on the other hand, provides a declarative approach to resource lifecycle management, where developers define desired resources and dependencies, and Pulumi automatically manages the creation, updating, and deletion of those resources.

5. Workflow and Versioning: Ansible employs playbooks to define and orchestrate complex deployment workflows. Playbooks can be versioned using source control tools like Git, allowing developers to track changes and roll back if necessary. Pulumi leverages modern development workflows through standard development tools like IDEs, Git, and CI/CD systems. By treating infrastructure as code, developers can leverage software development best practices, including testing frameworks, code reviews, and continuous integration.

6. Community and Ecosystem: Ansible has a large and active community with a vast collection of pre-built Ansible roles and modules available for various use cases and integrations with other tools. Pulumi, being a newer entrant, is rapidly growing its community and ecosystem, with a focus on collaborating with existing tools and frameworks to provide seamless integration and support.

In Summary, Ansible and Pulumi differ in their execution models, language support, cloud provider integration, resource lifecycle management, workflow and versioning capabilities, and community and ecosystem size.