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A. After the specified date, no code that introduces new scientific capabilities of the model can be introduced to the version being finalized. More specifically, a github "pull request" for completed code implementing the feature must be made before the feature freeze date/time. Example: all ACME v1 features must be have their coding complete and have a PR issued by 11:59:59 pm PT, .
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A. The integrators need time to bring all the new features to master including new tests. The coupled model team needs time for alpha and beta testing of the model.
Q. What's this about alpha and beta versions?
A. See the documentation at Branch, Tag, and Version name conventions. New science features are not introduced in alpha and beta tags in ACME.
Q. What if the feature is completed after the freeze but "turned off" and doesn't change answers and we'd like it in the v1 release?
A. You can still add such features to the code base but the testing must verify that the model is still bit-for-bit identical AND doesn't break the features that made it. If testing can not verify that, the feature requires Council approval This case is still under discussion.
Q. What about code for new diagnostics or new data sets?
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A. Wait until the maintenance branch has been established for the version being finalized. After that, master can accept answer- or climate-changing code for future versions.
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A. The build/test system will have a different feature freeze date but the same rules apply.
Q. When can I no longer make any changes at all to any part of the code base in the version being finalized?
A. That is the "code freeze" date and will happen shortly before the release.
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