diff --git a/text/0000-target-tier-policy.md b/text/0000-target-tier-policy.md index 96f622f29b7..596199a9407 100644 --- a/text/0000-target-tier-policy.md +++ b/text/0000-target-tier-policy.md @@ -91,6 +91,15 @@ requirements.) A target proposal is encouraged to quote the corresponding requirements verbatim as part of explaining how the target meets those requirements. +Note that a target must have already received approval for the next lower tier, +and spent a reasonable amount of time at that tier, before making a proposal +for promotion to the next higher tier. This policy leaves the precise +interpretation of "reasonable amount of time" up to the approving teams; those +teams may scale the amount of time required based on their confidence in the +target and its demonstrated track record at its current tier. At a minimum, a +target should normally go through multiple stable releases of Rust before +seeking promotion to the next tier. + In this policy, the words "must" and "must not" specify absolute requirements that a target must meet to qualify for a tier. The words "should" and "should not" specify requirements that apply in almost all cases, but for which the