The research paper examined the interaction effect between engagement and leadership style of employees and sustainable competitive advantage in FarmCAS, an agricultural and workforce management enterprise in Ado-Ekiti, Nigeria. This study is based on employee commitment, decisionmaking involvement, transformational leadership and participative leadership as major predictors of performance in an organisation in a resource-constrained SME environment. A quantitative crosssectional survey design was used, which was descriptive. Out of the total of 120 employees and managers, simple random sampling was used to send 92 structured five-point Likert-scale questionnaires, and of these questionnaires, 85 were found to be valid (92.4% effective response rate). Data were measured by the use of Partial Least Squares Structural Equation Modelling (PLS-SEM) in SmartPLS 4.0. The model used to measure was found to be highly reliable (Cronbach’s α > 0.80), composite reliable ( > 0.88), convergent valid (AVE = > 0.71), and discriminant valid (HTMT = < 0.85). The structural model showed important positive direct impacts on sustainable competitive advantage: Employee commitment (β ≈ 0.268, p = 0.001); Employee involvement (β ≈ 0.241, p = 0.003); Transformational leadership (β ≈ 0.312, p < 0.001); Participative leadership (β ≈ 0.289, p < 0.001) The model accounted for 61.4% of the variance in sustainable competitive advantage (R² = 0.614), with predictive relevance confirmed (Q² = 0.418 > 0). A robust synergistic interaction was observed between employee engagement and leadership style, with the overall interaction term (β ≈ 0.226, p < 0.001) and specific sub-interactions (β = 0.198–0.215, p = 0.004 to p = 0.002) all statistically significant. This indicates that leadership amplifies the impact of engagement on competitive advantage, and vice versa, producing stronger outcomes than when the factors are considered separately. This implies that leadership enhances the influence of engagement on competitive advantage and vice versa with greater results than the results of the factors individually. FarmCAS represents the way human capital factors are aligned to perform at a greater level, as a result of external restraints. There are the recommendations on the implementation of recognition programs, career development opportunities, and fair rewards to reinforce commitment, platforms of employee participation in decision-making to boost motivation and ownership