KD Kieran Duff
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Systematic Portfolio Manager · Live since April 2025

Process over conviction. Built one rule at a time.

I manage systematic strategies through a regulated partnership, $3.7M+ in live capital, and I write about how the work actually gets done. No hot takes. No PnL screenshots. Just the process.

Capital at risk. Past performance is not indicative of future results.
$3.7M+ Live capital
Apr 2025 Strategy inception
+47.34% All-time return (gross)
Performance · XAQP As of 1 June 2026 · Before fees (gross) · USD
Jun (MTD) +0.37%
YTD 2026 +8.21%
All-time (since inception) +47.34%
Max DD (12m) −6.20%
Sharpe (since incept.) 4.09
Sortino (since incept.) 5.68
Capital at Risk. Past performance is not indicative of future results. Figures are before fees (gross), denominated in USD, and reflect the live track record of XAQP since inception on 28 April 2025, as managed under Darwinex (Tradeslide Technologies Ltd). Returns are gross of costs; actual investor returns will be lower after fees. Where a monthly return is shown, the corresponding YTD return is shown alongside it.
Latest Letter 008 · 1 Jun 2026

Time under water: the metric your backtest ignores.

Systematic books model max drawdown but almost never model recovery time. Time-under-water reveals what allocators actually experience, and it belongs in your monthly reporting.

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Letters View all →
007 29 May Where AI actually helps in systematic strategy work 006 28 May Is your Sharpe ratio lying to you? 005 27 May The correlation trap most quants walk into 004 26 May The maths of ruin: position sizing from first principles 003 25 May Correlation: the silent killer of systematic portfolios 002 22 May Don't trust your backtest 001 21 May Your trading strategy will fail. Here is how to plan for it.
What people are saying

Thanks man. Really appreciate it. You're a big inspiration for why I went into algo trading.

D. Martin @dmartin_nq · via X

I've followed you since I learned you were also a Dante student. I really appreciate the time you take with everyone and Darwinex. You inspired me to re-open my old folders from 2018 and get back into automation alongside my discretionary trading. Trading is an insular game and I place zero faith in 99% of what I see, but I know a real one when I come across it.

Anonymous via X DM

Found you through @Trader_XO and immediately loved the content. I wish I could filter good content on X and avoid the noise!

Floppy22 @Sup2022a · via X
About

A systematic approach, in writing.

I'm Kieran Duff. I manage systematic strategies through a regulated partnership, with $3.7M+ in live capital. The strategy went live on 28 April 2025. I'm starting to write the things I wish someone had told me at the start of my career, because they were not, anywhere, written down.

If you can't write it down, you don't have a system.

The letter covers what I actually do: position sizing, risk allocation, drawdown management, regime detection, at the level of detail I'd want from someone twenty years ahead of me. You won't find calls, screenshots, or hot takes. You'll find process.

$3.7M+ Live capital
Apr 2025 Live since
4.09 Sharpe (since incept.)
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The letter, every Tuesday.

One long-form piece on how I run the book. No promotions, no third parties, no upsells.

By subscribing you agree to receive the letter. Capital at risk. Past performance is not indicative of future results. Nothing in this letter constitutes investment advice or a solicitation.