Documenting Legacy Code with LLMs

Approach 1: A Streamlined Approach

Challenge:

Legacy codebases often exceed LLM context windows, making comprehensive documentation difficult.

Solution:

  1. Create an Index – Outline key areas such as: Setup, File Structure, Business Logic, Database, Framework.
  2. On-Demand Generation – Generate documentation sections only when requested by users.
  3. Improve AI Understanding – Use vector embeddings of the codebase and implement Retrieval-Augmented Generation (RAG).

Role of Git History and LLM Access:

  • Version Tracking: Git history provides context for code changes, aiding in documentation.
  • Code Evolution: Helps LLMs understand why and how the codebase has evolved.
  • Enhanced Retrieval: Improves accuracy when combined with RAG-based documentation.

Approach 2: AI-Assisted Developer Communication

Concept:

Similar to how human developers understand code by discussing it with teammates, an AI system can learn through conversations with developers.

Implementation:

  1. Integration with Chatbots & Voice Assistants – Connect AI to project developers for real-time code understanding.
  2. Contextual Understanding – The AI system listens to and analyzes discussions in team meetings and chat groups.
  3. Adaptive Learning – The AI continuously refines its knowledge based on discussions and code changes.

This approach enables a dynamic and human-like understanding of legacy code while ensuring accurate and up-to-date documentation.

Approach 3: Code Visualization & Flow Mapping

Concept:

Visualizing code flow and relationships can help developers understand complex systems.

View Architecture on Figma