Self-Hosted Terraform: Options for TFE, Spacelift & Scalr

Choosing the right Terraform orchestration platform is crucial, especially when security, control, and private network access are top priorities. This often leads to evaluating Terraform Enterprise (TFE), the self-hosted Spacelift instance, and the self-hosted components of Scalr. While full self-hosting offers maximum control, it brings significant operational overhead. Understanding the nuances of each platform's self-hosted capabilities is key.

Why Self-Host Terraform Components?

The core drivers for incorporating self-hosted elements into your Terraform strategy include:

• Data Sovereignty & Security: Keeping sensitive data, configurations, and credentials within your network.
• Execution Control: Dictating the precise environment (OS, dependencies, networking) where Terraform operations run.
• Private Network Access: Seamlessly connecting to internal resources like private Version Control Systems (VCS) (e.g., GitHub Enterprise, self-hosted GitLab) and internal infrastructure endpoints.

Examining Self-Hosted Platform & Component Options

Let's look at the self-hosted offerings for each platform:

1. Terraform Enterprise (TFE) - Fully Self-Hosted

• Nature of Self-Hosting: TFE is HashiCorp's comprehensive, fully self-managed Terraform platform. You deploy and operate the entire TFE instance within your own infrastructure (on-premises or private cloud).
• Pros:
  • Maximum control over all aspects: data, security, execution environment, and network.
  • Supports air-gapped deployments, ideal for highly regulated or isolated environments.
  • Full ownership of the platform's operational lifecycle.
• Cons:
  • High operational responsibility: requires dedicated resources for installation, upgrades, maintenance, monitoring, and scaling of the TFE infrastructure itself.
  • Can be complex to set up and manage.

2. Spacelift - Fully Self-Hosted Version

• Nature of Self-Hosting: Spacelift offers a fully self-hosted deployment option where the entire Spacelift platform is installed and runs within your own AWS account. This is distinct from its SaaS offering that can use private workers.
• Pros:
  • Strong control over the platform and its data within your AWS ecosystem.
  • Customizable to specific security and networking requirements within your AWS environment.
  • Avoids reliance on a third-party SaaS control plane for core platform operation.
• Cons:
  • Significant operational burden for installing, managing, and scaling the Spacelift instance and its underlying AWS infrastructure.
  • Feature updates or new integrations might have a different release cadence compared to Spacelift's primary SaaS offering.

3. Scalr - Self-Hosted Agents within a Hybrid SaaS Model

• Nature of Self-Hosting: Scalr does not offer a fully self-hosted platform in the same way as TFE or the self-hosted Spacelift version. Instead, Scalr's "self-hosted option" refers to its self-hosted agents, which operate as part of its hybrid SaaS architecture. The control plane remains SaaS, managed by Scalr.
  • Run Agents: Execute Terraform/OpenTofu runs on your infrastructure.
  • VCS Agents: Enable secure connection from the Scalr SaaS platform to your private, self-hosted VCS instances (e.g., GitHub Enterprise, GitLab Self-Managed) without exposing them to the public internet.
• Pros (of Self-Hosted Agents):
  • Provides critical execution control and security for Terraform runs within your network.
  • Enables secure access to private VCS without direct internet exposure of the VCS.
  • Reduces the operational overhead compared to managing a full platform, as the control plane is SaaS.
• Cons (from a full self-hosting perspective):
  • The control plane (UI, API, core orchestration logic) is SaaS and managed by Scalr, not self-hosted.
  • Reliance on Scalr for the availability and security of the SaaS control plane.

The Hybrid SaaS Model: A Balanced Alternative

For organizations that need the execution control and private access benefits of self-hosting but wish to avoid the overhead of managing an entire platform, the hybrid SaaS model is a strong alternative. This model combines a vendor-managed SaaS control plane with self-hosted agents/workers running in your environment.

Key Benefits of Hybrid SaaS:

• Enhanced Security for Execution: Runs occur within your network; infrastructure credentials stay local.
• Private Resource Access: Agents natively connect to internal VCS, registries, and infrastructure.
• Controlled Execution Environment: You define the agent's OS, dependencies, and network.
• Reduced Operational Overhead: The vendor manages the complex control plane.

How the Platforms Fit into Hybrid SaaS:

• Terraform Cloud with Self-Hosted Agents: This is Terraform Cloud's hybrid SaaS offering, providing execution control.
• Spacelift (SaaS) with Private Workers: Spacelift's primary SaaS offering can use private workers, functioning as its hybrid model, distinct from its fully self-hosted version.
• Scalr: Is inherently a hybrid SaaS platform, with its self-hosted agents being a core part of this design.

Conclusion

When considering self-hosted Terraform solutions:

• Terraform Enterprise offers complete, unparalleled control but demands the highest operational investment.
• Spacelift's fully self-hosted version provides strong control within your AWS environment, also with significant operational responsibility.
• Scalr's self-hosted agents (within its hybrid SaaS model) provide crucial execution and private VCS access control without the need to manage the entire platform.

The choice depends on your organization's specific requirements for control, security, operational capacity, and whether a fully self-managed platform or a hybrid approach with self-hosted execution components best meets your needs. The hybrid model is increasingly popular for balancing these factors effectively.