Fidelity migrates to OpenTofu: 50,000 state files and 4 million resources

2025-10-06 · Publisher : OpenTofu · Domain : Cloud & DevOps

On 6 October 2025, the OpenTofu project publishes Fidelity Investments' migration story, which made OpenTofu its default engine. The estate covers over 2,000 applications, 50,000 state files and 4 million resources.

### What changes On 6 October 2025, the OpenTofu blog publishes an interview with David Jackson, VP of cloud automation and tooling at Fidelity Investments, on the company's migration from Terraform to OpenTofu. It is the testimony of a large financial account, published by the project itself: the statements are those of Fidelity's manager. ### Key facts - Estate cited: more than 2,000 applications on Terraform or OpenTofu, over 50,000 state files, more than four million cloud resources and over 4,000 state updates a day. - Trigger: Terraform's licence changes, which opened a discussion on open governance. - Method: proof of concept pushed to production, consultation of DevOps bodies, 70% adoption before the CLI switch. - OpenTofu is now the default for new deployments, and older Terraform versions are being phased out. - Lesson: switching the CLI is trivial; the difficulty lies in versions, CI/CD, governance and artifacts. ### Why it matters This is a quantified example of leaving Terraform in a large regulated organization, useful to consulting firms to size such a project. The effort lies less in code than in shared pipelines, module catalogue and governance. The testimony comes from the OpenTofu project itself: read it as a customer case, not an independent study. The figures are supplied by the company and were not independently verified in the article. ### Takeaway A large regulated account made OpenTofu its standard: the switch is feasible at scale when pipelines are shared.

Tags : Infrastructure as Code, Open Source, Plateforme engineering, DevOps