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+There are two classes of builder: *Supported* and *Unsupported*.  The basic policy is that if a supported builder goes red then we fix it right away.
+
+1.  It could be we just committed a patch that breaks Tahoe in a way that makes a test fail on that builder.  In this case we either:
+  1.   Revert that patch.
+  1.   Commit a new patch that fixes the previous patch (careful ...)
+
+2.  It could be that the new patch doesn't break Tahoe, but that the unit tests incorrectly think it does, in which case we either:
+  1.  Commit a new patch that fixes the unit tests.
+  1.  Commit a new patch that marks that test as "skip" on that builder.
+
+3.  It could be that something in the configuration of the build machine has changed which breaks Tahoe and/or Tahoe's unit tests.  In that case we either:
+  1.  Commit a new patch which makes Tahoe work on that new configuration.
+  1.  Get the administrator of that build machine to change the configuration so that Tahoe works again.
+
+In any of these cases, we might be unable to resolve the redness in a timely manner.  In that case we demote that builder from the *Supported Builders* page to the *Unsupported Builders* page, as linked from the *Buildbot* button at the top of every page on this site.
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