vite-core-environment-api

Configure per-environment SSR in Vite 6 by introducing explicit environments blocks in your vite.config.js, defining named environments like server and edge with their own consumer, build, and resolve options to isolate runtime settings.

Migrate Vite 5 projects to multiple runtime environments by adding an environments block with per-environment overrides while preserving top-level defaults, preventing silent configuration gaps and cross-environment conflicts during the transition.

You can isolate settings for edge workers and custom runtimes in Vite by defining named environments with explicit consumer declarations, provider integration, and dedicated output paths to ensure deterministic behavior across environments.

Explicit output paths are needed for multi-environment Vite apps to prevent cross-environment conflicts, ensuring that builds for different runtimes like client, server, and edge remain isolated and deterministic.

Vite 6 supports provider-based environments that encapsulate runtime specifics, allowing you to align client and server runtimes and ensure deterministic behavior across custom environments without relying on silent defaults.