I Built RepoGeist: An Open-Source AI That Uncovers the Ghosts in Your Git History

Description and use

RepoGeist lets teams explore repository history, detect deleted files, and explain their removal using a local AI model while preserving code privacy.

Problem

Developers lose visibility into deleted or abandoned code and decisions that are buried in Git history.

Outcome

RepoGeist enables teams to reconstruct and interrogate repository history locally, revealing deleted modules and undocumented motivations while preserving privacy.

Workflow

• 1. Configure RepoGeist with a repository root.
• 2. Run deterministic extraction to count commits, contributors, and trace file activity.
• 3. Identify deleted files and quiet branches via the Graveyard view.
• 4. Retrieve historical source of deleted files with Code Resurrection.
• 5. Use Ghost Chat, Commit Autopsy, or The Repository Speaks to generate explanations grounded in evidence.
• 6. Review AI responses that cite specific commits and files.
• 7. Optionally export investigation reports as Markdown or JSON.

Evidence

RepoGeist is a privacy‑first Git archaeology application that reconstructs a repository's past and lets you investigate it with a local open‑weight AI model.

Source

The deterministic half reads real Git objects. It counts commits and contributors, traces file activity, identifies quiet branches, finds files deleted from the analyzed HEAD, and retrieves their last historical versions without modifying the working tree.

Source

The generative half turns selected evidence into explanations. Ghost Chat answers questions about the repository. Commit Autopsy interprets a bounded diff. The Repository Speaks transforms factual milestones into a haunted chronicle, technical documentary, or developer retrospective.

Source

A real Ollama run with qwen2.5:3b produced a Ghost Chat answer citing the authentication deletion commit and auth/legacy.py while correctly acknowledging that the exact motivation was undocumented.

Source