RunbookInherit: Legacy Codebase Oral History Extractor & Bus-Factor Risk Scorer

The Problem

Solo developers and small engineering teams on HN and r/programming repeatedly describe the same dread when inheriting or acquiring a legacy codebase: undocumented tribal knowledge lives entirely in one person's head, and that person is leaving or has already left. RunbookInherit connects to a Git repo, analyzes commit authorship concentration, comment sparsity, and dependency age to produce a bus-factor risk score per module, then generates a structured 'oral history interview script' — a prioritized list of questions to ask the departing engineer before they go, mapped to the specific files and functions they alone have touched.

Target Audience

CTOs, solo developers, and micro-SaaS acquirers who are inheriting a codebase from a departing engineer or acquisition target

Monetization Angle

Freemium: free for repos under 50k lines; $29/mo for unlimited repos and PDF export; $99 one-time per acquisition due-diligence report

Recommended Tech Stack

Why Now

The micro-SaaS acquisition market (Acquire.com, MicroAcquire) has normalized small teams buying codebases they didn't write, making bus-factor risk a real pre-close concern for the first time.

MVP Scope

A CLI tool that takes a GitHub repo URL, outputs a per-file bus-factor score table, and generates a 10-question interview script for the top-risk author.

AI Angle

LLM reads the densest, least-commented modules and generates plain-English 'what does this actually do and why' questions targeted at the specific code patterns it finds confusing.

Primary Risk

Git history alone can be misleading if the repo has squashed commits or a single committer who was actually just merging others' PRs — requires a clear disclaimer and calibration step.

Validation Checklist

• Post 'What questions do you wish you'd asked before the last senior dev left?' in r/ExperiencedDevs and track response themes
• Find 5 recent Acquire.com buyers via LinkedIn and ask if bus-factor risk was a concern during due diligence
• Publish a free bus-factor scoring script on GitHub and measure stars and issues within 2 weeks
• Offer 3 free acquisition-readiness reports to founders selling on Acquire.com in exchange for testimonials

Who Would Pay For This

Likely buyers are engineering teams, platform leads, developer-experience teams, and technical founders. Start with CTOs, solo developers, and micro-SaaS acquirers who are inheriting a codebase from a departing engineer or acquisition target and look for teams already spending time or money on this workflow.

First 10 Users

Find the first 10 users by searching for recent complaints around "developer tools SaaS" in Hacker News, developer communities, GitHub issues, and niche Slack or Discord groups. Offer a concierge version first: manually solve the workflow for a few users, then automate only the repeated steps.

More Developer Search Paths

Why This Idea Has Legs

• Sourced from real discussions and complaints across Reddit and social media
• Cross-checked against recurring demand signals in the IdeaGenius archive
• Difficulty rated Medium — buildable by a solo developer or small team
• Clear monetization path from day one

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