Quant Journal

Notes from building QuantPrompt, the trading truths nobody tells you, stories from market history and rules tested against real traders. Free to read.

DiaryOct 9, 2026
Inside our backtest engine
A single-pass simulator we can read end to end, 46 indicators each tested for look-ahead, realistic fills and costs, and stress tests that check a result before you trust it.
5 min read
Hard truthsOct 9, 2026
10 trading truths nobody tells you
What a backtest can and can't tell you, why costs and a few lucky trades decide more than you think, and what the research says about active traders.
6 min read
Quant museumOct 9, 2026
Fortunes made with leverage: what set the winners apart was knowing how to lose
Livermore, Soros, Paul Tudor Jones and Bill Hwang all used leverage. The difference between the ones remembered as winners and the ones who lost everything was position size.
6 min read
Quant vs traderOct 9, 2026
Same 10 years, three approaches: SPY
Buy and hold, a 200-day trend rule and an RSI rule on SPY from October 2016 to September 2026, run through our engine with costs included.
5 min read

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