Gruntwork's GCP Landing Zone and GCP Fabric FAST both stand up a governed, multi-project Google Cloud foundation with Terraform. Fabric FAST is Google's open-source landing-zone toolkit: a design for a GCP organization plus a Terraform reference implementation you operate yourself. Gruntwork takes the best practices behind Fabric FAST and combines them with IaC best practices and opinionated defaults, delivered as OpenTofu/Terraform code you own, with support. The result is quick to onboard, fast to value, scalable, and maintainable.
What each one is
GCP Fabric FAST is the organization-wide landing zone toolkit inside Google's open-source cloud-foundation-fabric repository, licensed under Apache 2.0. It has two parts: a design of a GCP organization with the elements enterprises typically need, and a reference implementation of that design in Terraform. Fabric FAST is built as sequential stages: an organization-setup stage that bootstraps the organization and resource management, an optional VPC Service Controls stage, shared stages for security, networking, and a project factory, and an applications-and-operations tier. Each stage passes its outputs forward to the next through predefined contracts, and stages are typically owned by different teams, such as the security team and the networking team. Google expects users to customize Fabric FAST, modify the code, and keep only the stages they want, then operate it themselves.
Gruntwork's GCP Landing Zone is an opinionated landing zone delivered as OpenTofu/Terraform code you own. It stands up organization, folder, and project structure, identity and access management, network foundations, and guardrails, with code-driven project vending through a pull-request workflow and a GitOps platform run by Gruntwork Pipelines, Drift Detection, and Patcher. Gruntwork takes the best practices from Fabric FAST and combines them with IaC best practices and Gruntwork's opinionated defaults.
Gruntwork and GCP Fabric FAST at a glance
| Capability | Gruntwork GCP Landing Zone | GCP Fabric FAST |
|---|---|---|
| What it is | An opinionated GCP landing zone delivered as OpenTofu/Terraform code you own, with hands-on onboarding | An open-source design plus a Terraform reference implementation you clone and run yourself |
| IaC | OpenTofu/Terraform | Terraform for the reference implementation; the design could in theory use other tools |
| Deployment workflow | PR-driven GitOps with Gruntwork Pipelines: plans run on pull requests, applies run on merge, inside your own GitHub or GitLab runners | Sequential stages applied in order, where each stage's outputs feed the next; optional stages configure your CI/CD provider |
| Ongoing operation | Drift Detection opens a PR when live infrastructure drifts from code; Patcher raises PRs to keep modules up to date | You own operation, upgrades, and drift management for the code you customized |
How Gruntwork builds on Fabric FAST's best practices
Gruntwork is an alternative to Fabric FAST: you use one or the other to stand up your Google Cloud landing zone. At the same time, the best practices behind Fabric FAST carry straight into Gruntwork's landing zone. The organization design, the staged separation of security, networking, and project-factory concerns, and the Terraform patterns Fabric FAST encodes are the same practices Gruntwork builds on. On top of that, Gruntwork adds IaC best practices and opinionated defaults, then wires the landing zone into a ready-made GitOps platform: Gruntwork Pipelines for plan-on-PR and apply-on-merge, Drift Detection that opens remediation PRs, and Patcher for versioned module updates. A landing zone is not a one-time project, it is a product you own, and your team is responsible for every Google Cloud change, security update, module update, and standards drift. With Fabric FAST, that ownership is entirely yours: you adopt the reference implementation, customize the stages, and operate and upgrade them with your own team. Gruntwork delivers the same kind of code and keeps supporting it. The published GCP Landing Zone is positioned to cut time to production by 60%.
When to use each
GCP Fabric FAST
Use Fabric FAST directly when you want Google's open-source landing-zone design and its Terraform reference implementation, and your team is ready to adopt it, customize the stages, and own its operation and upgrades, for Google Cloud alone.
Gruntwork
Use Gruntwork when you want Fabric FAST best practices with opinionated defaults, delivered as OpenTofu/Terraform code you own and run through a GitOps platform with drift remediation and patching, with hands-on onboarding and migration support.
What is GCP Fabric FAST?
Fabric FAST is the open-source, organization-wide landing zone toolkit in Google's cloud-foundation-fabric repository. It combines a design for a GCP organization with a Terraform reference implementation, organized as sequential stages you deploy and operate yourself.
Is Gruntwork a replacement for Fabric FAST?
Yes. Gruntwork's GCP Landing Zone is an alternative way to deploy a Google Cloud landing zone: instead of adopting and operating Fabric FAST's Terraform reference implementation yourself, Gruntwork stands it up as OpenTofu/Terraform code you own. It takes the best practices behind Fabric FAST and combines them with IaC best practices and Gruntwork's opinionated defaults.
Does Fabric FAST use Terraform?
Yes. Fabric FAST pairs a design for a GCP organization with a Terraform reference implementation that Google expects you to customize, and you run it yourself in stages.
