Roost is an Environments as a Service (EaaS) platform that on-demand creates an ephemeral pre-production environment. By inspecting source-code repositories (e.g. GitHub, GitLab, BitBucket) the Roost platform auto-discovers and maps environment configuration then optimizes it using the power of machine learning. Engineers can effortlessly spin up an ephemeral environment on-demand, at a specific time, or at every pull request. Once created, a Roost preview environment URL can be shared with stakeholders to validate their deliverable. The whole release cycle gets accelerated using this fast feedback loop accelerating development velocity and pull request merge success.