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alpha = after all new features have been integrated. This version is run for a decade or more to look for instabilities not detected by short running development/integration testing. The first alpha tag is made after all the features from the feature freeze have been integrated to master.
beta = after alpha. Versions used for tuning. The first beta tag is made after the coupled simulation group says alpha testing is finished.
rc = release candidate. Near-final version. Checked for documentation, portability. The first rc tag is made after the coupled simulation group determines beta testing is finished AND after a code freeze. The rc versions and released versions are nearly identical.
Tag sequence before v1.0 may look like: v0.1, v0.2, .... v0.14, v0.15.....v1.0alpha1, v1.0alpha2, ...., v1.0beta1, v1.0beta2, ..., v1.0rc1,v1.0rc2, ...., v1.0
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