The persistent underrepresentation of First Peoples in computing education reflects enduring legacies of colonialism embedded in curricula, pedagogies, and digital infrastructures. This position paper introduces the emph{Decolonial Mindset Stack (DMS)}—a seven-layer conceptual framework that scaffolds computing educators through stages of mindset transformation: textit{Recognition, Reflection, Reframing, Reembedding, Reciprocity, Reclamation}, and textit{Resurgence}. Each layer is grounded in Freirean critical pedagogy and Indigenous methodologies, aligning with relational lenses such as “About Me,” “Between Us,” and “By Us.” Together, these dimensions foster self-reflexivity, relational accountability, and Indigenous sovereignty in computing education. The DMS reframes underrepresentation as an outcome of systemic exclusion and a call to action for reimagining how computing education can be co-developed with and led by Indigenous communities. We present the theoretical grounding, illustrate implementation pathways, and argue that indigenisation is not an endpoint but a sustained ethical commitment to transformative justice in computing education.