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In general a contributor that makes sustained, welcome contributions to the project may be invited to become a committer, though the exact timing of such invitations depends on many factors. Sustained contributions over 6 months is a welcome sign of contributor showing interest in the project. A contributor receptive to feedback and following development guidelines stated above is a good sign for being a committer to the project. We have seen contributors contributing 20-30 patches become committers but again this is very subjective and can vary on the patches submitted to the project. Ultimately it is the Ambari PMC that suggests and votes for committers in the project.
Contribution Flow