The concept of an ePortfolio was introduced in 1999 as an electronic learning record and further developed to overcome the limitation of learning management systems lacking persistent storage for learning artifacts. Nowadays, educational platforms have evolved towards personal learning environments and social media platforms, enabling the creation, exploitation and archiving of activity traces, learning outcomes, and learning analytics thanks to built-in export and sharing features. This paper presents the design and implementation of archiving and sharing services in Graasp, a general-purpose learning platform. These features enable implementing Graasp as an ePortfolio platform, allowing students to archive learning artifacts as evidence of competences and activity traces for analytics-driven self-assessment. Additionally, we discuss user requirements for designing such general ePortfolio services elicited from the analysis of functionalities of the Mahara popular ePortfolio platform and from a participatory design session with expert users of Graasp.