Bus Factor

The number of people who would have to be hit by a bus (or simply leave) before a project or company is in serious trouble because too much knowledge or access sits with too few. A low bus factor is a risk.

Why it matters

A bus factor of one, where only the founder knows the code, the accounts, or the key relationships, is a hidden fragility. Documenting knowledge and spreading access reduces risk and is scrutinized in diligence.

For example

Only the founder knows how the billing system works and holds the server passwords, a bus factor of one that scares investors in diligence.

Go deeper

Survive The Bus Factor: Strategies For Protecting Your Codebase Forbes Technology Council · article This names the exact risk you are worried about: when one person is the only human who understands your codebase, your bus factor is one, and a single resignation or bad month can freeze the whole product. It is written by Adam Tornhill, who built a company (CodeScene) around measuring this, so the advice is concrete rather than hand-wavy. Read it as a checklist for reducing dependence on one person, not as a blanket reason to never hire a solo developer. Open forbes.com →

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Also in Starting Up

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