How to auto-create preview environments on every PR

Preview environments are temporary, isolated setups created on demand to test code changes within a specific branch before merging into the main branch, triggered by Git events like opening a pull request. They provide a clean, production-like environment for testing, avoiding the bottlenecks and inconsistencies found in traditional shared staging environments. These environments are automated, isolated, and ephemeral, automatically destroyed once the pull request is resolved, which helps keep costs low. On platforms like Northflank, preview environments can be provisioned as full-stack setups, including databases, queues, and microservices, and can be managed using a blueprint system for automation and control. This approach enhances software delivery by speeding up the feedback loop, catching integration bugs early, and eliminating deployment queues, while also offering cost management features such as automatic teardown and idle shutdown policies.