Michal Sokolowski developed runtime configuration file support for stack deployment and preview in the spacelift-io/spacectl repository. He introduced a new CLI flag to accept user-defined runtime configuration files, encapsulated settings in a dedicated Go struct, and updated the run trigger logic to read and pass these configurations to the GraphQL mutation layer. This approach enabled flexible, reproducible deployments across different environments by reducing manual configuration steps and potential errors. Michal’s work demonstrated depth in CLI development, configuration management, and GraphQL integration, delivering a targeted feature that improved deployment workflows without addressing bug fixes during the development period.