[03] Designing a Personal Commitment Line — Two Loans, One Defense System

This is Part 3 of a 6-part series: Building Investment Systems with Python

The Corporate Playbook

Every major corporation maintains a revolving credit facility — a pre-arranged borrowing line they can draw from instantly during a crisis. They pay a commitment fee for the privilege of having this standby capacity, even when they don't use it.

The logic is simple: the time you most need to borrow is exactly when borrowing becomes hardest.

This applies to individuals too. A securities-backed loan shrinks when your portfolio drops. You need a second source — one that's independent of market conditions.

Correlated vs.…