`process.env.NEXT_PHASE` was moved in https://github.com/vercel/next.js/pull/20900 to be set during `staticCheckSpan.traceAsyncFn`. I believe this to be a mistake, the NEXT_PHASE should be set earlier in the code execution.
On a personal note, this impacts an application I am developing where we rely on the environment variable `NEXT_PHASE` to be set but is `undefined` when we check it.
Co-authored-by: JJ Kasper <jj@jjsweb.site>
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