Personal blog. I write about what I learn as I am learning it

Safe Withdrawal Rate by Age: Why 4% Isn’t One Number

The “4% rule” gets repeated like it’s one universal number, but the safe withdrawal rate by age isn’t actually flat — it moves depending on how long your money needs to last, which is another way of saying it depends heavily on your age when you start withdrawing. I built my own withdrawal calculator specifically because a flat percentage didn’t fit an early-retirement timeline, and the more I dug into the math, the more the “4%” felt like a rounding of something that should really be a curve.

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Dynamic Route Planning Software, Explained

“Dynamic route planning software” gets thrown around as a marketing word more than a technical one, and it’s worth pinning down what it actually means before you pay for it. I’ve built routing models for real operations for over twenty years, and the honest answer is: dynamic isn’t a feature you either have or don’t — it’s a spectrum, and most businesses searching for it don’t actually need the far end of it.

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How to Retire Early: The Math That Actually Matters

People ask me how to retire early like there’s a secret I’m withholding — some clever investment, a trick with real estate, a system nobody else knows about. There isn’t. I retired early, I still don’t have a boss more than a decade later, and the math behind it is boring enough to explain in two paragraphs. The hard part was never the math. Here’s the version I wish someone had handed me plainly, instead of making me piece it together from forum threads.

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Deputy Alternative: Free Staff Scheduling, No Per-User Fee

The search for a Deputy alternative almost always starts the same way: the roster grows, the per-user fee grows with it, and someone asks whether a scheduling tool should really cost as much as a part-time shift. After twenty-plus years building optimization models professionally, I built my own answer — my free staff scheduling optimizer — and made it free: no per-user fee, no account, and a real solver doing the actual scheduling work.

When I Work Alternative: A Free Scheduling Optimizer

Most people hunting for a When I Work alternative aren’t angry at the product — they’re doing per-user math. Multiply a monthly fee by every employee on the roster, add the time-tracking add-on, and a “cheap” tool quietly becomes a real line item. I’ve built scheduling optimization models for twenty-plus years, and my answer to that math is my free staff scheduling optimizer: it costs nothing, needs no account, and — unlike most scheduling apps — it actually builds the schedule instead of giving you a nicer grid to fill by hand.