This study implemented and evaluated the innovative use of a performance-based assessment platform to support the development of self-regulated learning (SRL) in senior primary students as they completed programming tasks. We embedded SRL support features into a performance-based assessment platform as scaffolding to help the students implement problem-solving strategies. A mixed-methods approach was adopted to evaluate the intervention. The students' perceptions of their SRL skills after working through the programming tasks were measured by a survey of 45 students. The quantitative results suggested that the students benefited from the performance-based assessment platform in developing their SRL skills. A thematic analysis of interview data from 20 students further indicated that the embedded SRL scaffolding and automatic marking function helped them to solve the programming tasks. The results demonstrate that a well-designed performance-based assessment platform with embedded SRL support can be an effective tool for developing students' SRL. The qualitative results further revealed that algorithmic thinking is an aspect of programming for which students need more SRL support.