Development Environments platforms provide consistent, reproducible dev-time runtime infrastructure — replacing 'works on my machine' drift with version-controlled environment definitions that work identically for every developer. Core capabilities include container-based environment definition (devcontainer.json, Nix, or similar), cloud-hosted dev VMs or containers accessible through the browser or local IDE, per-project templates, fast spin-up and teardown, credential and cloud-access brokerage, and integration with IDEs and SCM for seamless developer onboarding. The category has expanded from local dev-environment managers (Docker Desktop, dev containers) to cloud-hosted dev platforms (GitHub Codespaces, Gitpod, Coder) that decouple the development experience from the physical laptop.