Abstract- The role of a Software Engineer Technical Lead (Tech Lead) has become increasingly critical asorganizations accelerate digital transformation and adopt emerging technologies. Beyondcodingexpertise, Tech Leads are expected to combine technical decision-making, architectural guidance, and problem-solving with leadership, mentorship, and cross-functional collaboration. This paper presents a systematic review conducted under PRISMA guidelines, synthesizing findings fromfour key studies published between 2010 and 2024. The review identifies five major domains of responsibility: (1) technical leadership and architecture decision-making, including technologyselection and coding standards; (2) team leadership and mentorship, with an emphasis onguidingjunior engineers and cultivating team culture; (3) stakeholder communication and collaboration, bridging technical and non-technical perspectives to align projects with business goals; (4) problem-solving and crisis management, addressing technical challenges and maintainingproject continuity; and (5) adaptation to emerging technologies, particularly in areas such as AI andcloud systems. The findings highlight that effective Tech Leads not only safeguard softwarequality but also drive organizational alignment, foster innovation, and sustain competitive advantage. This guide provides a comprehensive overview of the competencies and expectationsdefining the Tech Lead role, offering actionable insights for both practitioners and organizationsnavigating this vital leadership position.