ABSTRACT Organisations’ increasing adoption of lightweight automation, such as robotic process automation (RPA), raises concerns about the associated systems’ robustness and security, with data-security concerns becoming further accentuated when tools of this sort are deployed for handling of potentially sensitive data. However, literature on designing these tools in a manner mitigating risks related to organisational data security has remained scarce. This paper addresses this gap by presenting a study in which RPA was successfully designed for a process wherein the software robot handles sensitive personal data. Informed by work on the mindlessness of automation, sociotechnical envelopment, and security by design, this empirical study, employing action design research at Wärtsilä Corporation, pointed to three design principles, related to envelopment, access rights, and audit trails. By adhering to these, Wärtsilä created envelopes around the robot that afford the automation’s safe operation and processing of the sensitive data. This research advances the theory of sociotechnical envelopment’s design and deployment by introducing a novel approach in security by envelopment to elaborate on the security-oriented envelopment of mindless automation agents. The paper also discusses the practical utility of the artefact designed, in terms of both design and evaluation.