TL;DR — the short answer

Terraform (or OpenTofu) is still the safest default for most teams in 2026: the largest provider ecosystem, the most modules and hiring pool, and one workflow that works across AWS, GCP, Azure and beyond. The tool is no longer open source, though — since 2023 it ships under the Business Source License, and the open-source continuation of the same codebase is OpenTofu .

Pulumi is the best fit when your team thinks like software developers: real programming languages (TypeScript, Python, Go, C#), real unit tests, and reusable abstractions built with loops and classes instead of a DSL. You pay for that power with a smaller ecosystem and a team that must actually be able to program.

CloudFormation is the right answer more often than the internet admits — if you are genuinely AWS-only. There is no state file to secure, no licence to think about, no per-resource SaaS bill, and new AWS services land here first.…