The present study reports on a collaborative writing project initiated and completed by 18 Iranian English language learners enrolled in an online writing course. Using a wiki as the core element of the project, the aim of the course was fostering learner autonomy in online settings based on the collaborative autonomous language learning framework proposed by Kessler and Bikowski (2010). The outcome of collaborative writing project was a text created in a wiki, which was manually analyzed from the very beginning of writing to the final revisions and reflections to find autonomous alterations made by student writers. The findings of the study revealed student-writers' autonomous contributions in the form of alterations to the text which were accomplished interdependently with peers through alterations such as "commenting" as an instance of scaffolding to reach a shared goal. Other types of autonomous alterations such as "adding new information;" "deleting existing information;" "correction of information;" "clarification;" "synthesis;" and "reflection" were observed in the final product. Frequent occurrence of peer correction with regard to content and form was a discriminating finding of the current study. Also, despite the initial goal which was completion of the project exclusively by learners, teacher intervention was witnessed throughout the process. To study the role of teacher in depth, a semi-structured interview about the roles of a teacher in a collaborative autonomous learning was conducted. The data from the interview went through a manual thematic analysis to find the themes related to the learners' perceptions of teacher's roles. The findings revealed a need for a teacher as a facilitator and resource, which highlighted students' demands for motivation and content knowledge from teacher in an autonomous contribution to completing a collaborative project.