An application can be converted to new programming language or framework. A source application written for a legacy framework is analyzed and divided into smaller segments of code. The smaller segments are evaluated for quality in view of best practices design for writing applications. A rubric is determined for each segment and compared to a best practice threshold. Segments can be evaluated for features that can be passed through a model. The model converts the features into new code adapted for target framework. Machine learning and rules databases are updated with details of the conversion.