sandbox-migrate-to-next

Install @cloudflare/sandbox@next, switch the container image to cloudflare/sandbox:next, and rewrite code using the replacement map: exec returns a process handle instead of a buffered result, sessions are removed in favor of per-launch cwd/env, and terminals use createTerminal plus connect.

sandbox.exec now takes an argv array and returns a process handle immediately; process start no longer means command completion. Use handle.output(), waitFor* methods, logs, and kill with numeric signals to manage execution.

No. Stable and @next control protocols are incompatible both ways, so gradual rollout leaves a broken mixed window. Production cutover requires a single deploy with wrangler --containers-rollout=immediate, and pre-deploy process and terminal IDs become invalid.

No. Default and named sessions are removed; pass cwd and env per launch or use a shell script. gitCheckout is gone too—run git through argv-based exec, such as cloning with ["git", "clone", ...].

Do not use it for day-to-day work on stable (use sandbox-stable), for brand-new @next projects (use sandbox-next), or for deprecated-API cleanup that stays on stable. Self-deployed bridges should also remain on stable since they are not part of the preview line.