Worked on backend development for the lnbits/lnbits repository, focusing on improving payment processing reliability and numeric data handling. Addressed a bug in the lndrest API integration by explicitly converting fee_msat values from strings to integers, which prevented type-mismatch errors during payment status processing. Enhanced fee calculation logic by normalizing fee_reserve values to ensure all fees remained positive, reducing the risk of negative reserves. These targeted Python changes improved the stability and resilience of the payment system, reduced runtime errors, and simplified future maintenance. The work contributed to more accurate fee reporting and increased reliability for merchants and end users.