The Katokkon chili, an important Toraja cash crop, is increasingly threatened by climate change, necessitating climate-resilient soil management strategies. This study assessed the synergy of biochar and compost in enhancing soil carbon sequestration and improving Katokkon chili performance within low-emission farming systems. A farmer-led field experiment was conducted in Ullin Rembon Village in 2024 involving 12 farmers cultivating 150 m² plots. A split-plot design was applied, with two genotypes—L1 (Limbong) and L2 (Leatung), as main plots and six compost–biochar ratios (R0–R5) as subplots, replicated four times. The L1R4 treatment (20% compost + 80% biochar) resulted in the highest improvement in plant performance, producing 2.511 g plant⁻¹, a 54.60% increase over L1R0. Soil carbon stock increased across treatments compared to the initial value of 33.82 ton ha⁻¹. The highest carbon stock was recorded under R5 (100% biochar) at 51.93 ton ha⁻¹, followed closely by R4 (20% compost + 80% biochar) at 51.06 ton ha⁻¹, reflecting substantial carbon accumulation consistent with the graph. These results, supported by an R² of 0.791 explaining 79.1% of yield variability, confirm that compost–biochar synergy effectively enhances soil carbon storage, improves plant growth, and strengthens the climate resilience of Katokkon chili production systems.