This study examines whether technology-based performance tasks can mediate communicating in English and enhance language learner engagement. This study investigated how low-proficiency Japanese English-language learners could change their attitude toward communicating in their target language by completing a performance task that involved making and presenting a digital portfolio, requiring linguistic and contextual self-mediation. The study adopted a questionnaire with two types of questions: one type was scored on a three-point Likert scale and the other included open-ended questions about the performance task; the questionnaire was completed by 33 and 28 students in the first and second semesters, respectively. Data from the open-ended questions were analyzed qualitatively from a phenomenological perspective. Students' comments showed that they positively engaged in the performance task throughout the two semesters by reflecting on themselves as English learners, with some difficulty mediating in their first and second languages.