This report synthesises findings from 15 peer-reviewed papers addressing the following research question: What is the impact of replacing explicit reward models with Directional Preference Alignment on the pass@k accuracy of code generation models across low-resource programming languages. Large Language Models (LLMs) have garnered remarkable advancements across diverse code-related tasks, known as Code LLMs, particularly in code generation that generates source code with LLM from natural language descriptions. This burgeoning field has captured significant. 6 claims were extracted from source literature; 6 were independently verified against retrieved documents. An automated multi-reviewer quality assessment produced a score of 8.3/10. This report is a machine-generated literature synthesis and does not constitute original research.Research goal: What is the impact of replacing explicit reward models with Directional Preference Alignment on the pass@k accuracy of code generation models across low-resource programming languages?Autonomous literature synthesis. Automated review score: 8.3/10. Full text and citation available at Assignee Research.