AAppicLab

Blog

Notes on finance, tool development, and design.

9 min

Should Young People Lever Up Early? A Look at Lifecycle Investing

Lifecycle Investing argues that young people should run 2x leverage to spread risk across their whole lives. But even if you're convinced — to get 2x index exposure, should you use a 2x ETF, a lump-sum personal loan, or broker margin? The costs, decay, and blow-up risk of the three paths differ enormously.

Lifecycle InvestingLeverage2x ETF
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9 min

Lump Sum or Dollar-Cost Averaging? Use the Risk Report to See Your Real Odds

The scariest part of borrowing to invest isn't losing money — it's hitting a crash in year one. I added a Monte Carlo risk report to the loan-to-invest calculator: 100,000 paths per scenario, comparing lump sum vs. DCA, buying half, and phased entry — and I accidentally found that "buy half first" might really hold up.

Borrowing to InvestLump Sum InvestingDollar-Cost Averaging
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8 min

When did you last run a health check on your wallet? 6 ratios to test your financial fitness

We get a physical every year, yet we rarely give our finances a check-up. Use six metrics — debt ratio, current ratio, quick ratio, emergency fund, runway, and debt service ratio (DSR) — to see whether your financial fitness is healthy enough, and whether you can take on one more loan.

Financial HealthFinancial RatiosDSR
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8 min

Borrowing to Invest: Reckless Gamble or Rational Choice?

"Borrow cheap money, earn expensive returns" sounds like free money — but leverage magnifies both gains and losses. Use the calculator to compare a loan-funded lump sum vs. dollar-cost averaging, then look at the break-even return rate that decides who wins.

Borrowing to InvestPersonal LoanHome Equity Loan
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7 min

How Much Retirement Are You Drinking Away? The Latte Factor and the Power of Compounding Small Change

A daily $5 coffee could grow to nearly $180,000 in 30 years. The Latte Factor isn't about quitting coffee — it's about understanding the opportunity cost of every dollar you spend.

Latte FactorCompound InterestFinancial Independence
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8 min

Rent vs. Buy Calculator Guide: Break-Even Year, Net Wealth, and Hidden Costs

Buying vs. renting: hidden costs, opportunity costs, price-to-rent ratio, and a 30-year net worth simulation

Buying a HomeRentingReal Estate
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8 min

FIRE Calculator Guide: How to Calculate Financial Independence and Retire Early

How do you calculate financial freedom? 3 steps to break down the FIRE movement + a super useful retirement calculator

FIRERetirement PlanningFinancial Independence
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3 min

Taipei Food Library｜A Hub of Threads-Recommended Restaurants (Ongoing)

Taipei food recommendations from the Threads community, organized into a series: business lunches, group-dining spots, and no-time-limit cafés — one entry point to browse and work through at your own pace.

Taipei FoodFood MapBusiness Lunch
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7 min

Taipei No-Time-Limit Cafés｜Work & Study Spots That Won't Rush You Out (With Map)

A curated list of Taipei's weekday no-time-limit cafés from Threads recommendations — co-working spaces, library-quiet rooms, and late-night cafés — with a full map and my top 3 picks.

Taipei CafésNo Time Limit CafésWork-Friendly Cafés
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7 min

Taipei Business Lunch Guide｜Threads' Top Steak, Yakiniku & Sushi Picks (With Map)

A curated list of Taipei business lunches from Threads recommendations — steak, yakiniku, and sushi/Japanese all in one place — with an interactive map and the spots I most want to try.

Taipei FoodBusiness LunchTaipei Steak
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8 min

Taipei Must-Eat Food Guide｜Threads' Worth-Eating-Again Taipei Restaurant List (With Map)

A Taipei must-eat list curated by the Threads community — breakfast, hotpot, Japanese, international, street food, and bistros all in one place — with an interactive map and the spots I most want to try.

Taipei FoodFood MapTaipei Street Food
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