Move the source, binaries and corresponding signature files to the release dist site: https://dist.apache.org/repos/dist/release/incubator/madlib/ .
See section above on committing artifacts to the dev dist site and follow the same process for the release dist site.
Update the main website with new version GA info (see previous examples already on the site): http://madlib.incubator.apache.org/
Update the wiki the user docs link to point to the correct version of the docs and also update any version numbers / links in the page content: http://madlib.incubator.apache.org/docs/latest/

Announce the Release

General Apache information regarding announcing a release may be found here.

Announce the release on user@ and dev@ mailing lists. See example email of past announcement.

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Miscellaneous

Some of the content of this page came from the Apache HAWQ project, which is another good guide for release process: https://cwiki.apache.org/confluence/display/HAWQ/Release+Process%3A+Step+by+step+guide

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