A person who contributes to a project, cause, or field; neutral modern term.
彼はオープンソースプロジェクトの貢献者だ。
He is a contributor to the open-source project.
tributary person
Historical term for a person who pays tribute to a ruler or state; rare in modern usage.
古代中国では、周辺国の貢献者が皇帝に貢物を納めた。
In ancient China, tributary persons from neighboring countries offered tribute to the emperor.
Compound of 貢献 (contribution) + 者 (person). The historical sense derives from the older meaning of 貢献 as 'tribute'.