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StatOasis · by Ali Casey

Stop guessing. Start building.

Research, build, test, combine, deploy: the loop that turns confidence into conviction.

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Is this you?

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Illustrative: a clean backtest is a hypothesis, not proof.
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  • 5,800+read OverFitnewsletter
  • 3,500+members inthe community
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  • 40+deep diveresearch articles

The loop most traders skip three steps of.

Five stages, running as a loop - every live strategy feeds the next round of research. The red shortcut is the one most traders take instead.

Most traders follow this path and call it done.
1

Research

Start from a behavioral hypothesis, not a prediction.

2

Build

Turn the hypothesis into rules, not a curve fit.

3

Robustness test

Out-of-sample, walk-forward, across regimes the optimizer never saw.

4

Portfolio construction

Combine strategies that fail at different times.

5

Live deployment

Size it, monitor it, plan the drawdown before it comes.

Most traders follow this path and call it done.

  1. 1

    Research

    Start from a behavioral hypothesis, not a prediction.

  2. 2

    Build

    Turn the hypothesis into rules, not a curve fit.

    ↷ Most traders follow this path and call it done.

  3. 3

    Robustness test

    Out-of-sample, walk-forward, across regimes the optimizer never saw.

  4. 4

    Portfolio construction

    Combine strategies that fail at different times.

  5. 5

    Live deployment

    Size it, monitor it, plan the drawdown before it comes.

back to research

Can you survive a decade of real markets?

A decade of markets. Five decisions. About eight minutes. See how your instincts hold up against the regimes that broke real strategies, then see the trading personality your choices reveal.

Start: Survive the Decade

I'm Ali Casey.

I build systematic trading strategies and teach the workflow behind them. Not a content creator. A system builder who happens to teach.

More about me →
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Happy Members

5.0
3.5K+

Algo trader since 2014

Here is how I can help you.

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Overfit - the newsletter

Skip the hype. Trust the data. One practical, evidence-driven takeaway per issue: strategy testing, portfolio construction, market structure, and the mechanics behind systematic trading - every claim with the backtest behind it. Publishing since 2024, formerly The AlgoTrader.

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Algo Trading Masterclass

The complete build-a-system workflow, taught end to end: finding an edge, testing it honestly, assembling strategies into a portfolio, and putting it live - the same process behind every study I publish. Currently open as a waitlist.

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Community

Where builders share strategies, code, and feedback. Get plugins, correlation book, indicators and more. Free to join today.

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Digital Products

Everything you can download and use the same day: books, strategy packs, and tools - starting with 36 Ways to Buy the Dip, backtested mean-reversion entries for systematic dip-buying, every variant tested, every result shown. New products land here as they ship.

Learn more→
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AlgoChef

The validation layer I built for the step most traders skip: pressure-testing a strategy before it risks real money. Launched 2026.

Learn more→

Latest from StatOasis YouTube channel

The "Dumb Money" Beat the Smart Money (4,889 Backtests)

The "Dumb Money" Beat the Smart Money (4,889 Backtests)

Aug 3, 2026

I Analyzed Every SPY Gap Since 1993. Here's What I Found.

I Analyzed Every SPY Gap Since 1993. Here's What I Found.

Jul 20, 2026

The Only Setup That Won 100% of Its Backtests (33 Years of Data)

The Only Setup That Won 100% of Its Backtests (33 Years of Data)

Jul 6, 2026

How This Part-Time Trader Stopped Doubting His System

How This Part-Time Trader Stopped Doubting His System

Jun 22, 2026

What you won't find here.

No trade calls. No daily predictions. No PnL screenshots. This is for traders who want to understand how to build trading systems, how they behave in different market regimes, when they break, and why. If that's not you, there are plenty of other places, and no hard feelings.

What traders say.

rodolfo berrocal's photo

rodolfo berrocal

Hello, my name is Rodolfo Berrocal, I'm from Lima, Peru. I just stopped by to thank you for all the great work you do. I'm doing my best to understand your videos since I don't speak English very well, but I'm still learning a lot from you. I'm just getting started in the world of algorithmic trading, and it's going well for me. Thank you again, and blessings.

Tommy's photo

Tommy

Dear Ali, your attention to detail - and people - was always bar none. No question, you are our Financial Guru, while also a loving/caring figure so you deserve our utmost respect! Thank you for all your shared experience and everyday hard work for our not-only-financial wellfare! :)

Chad's photo

Chad

I’ve been in the program since Feb, have found a way to create and find a lot of pretty good algos, but magic sauce happens when we combine the uncorrelated “pretty goods”. Happy to report since Feb, up 28pct and am now in maintenance mode working on the process instead of reflexively reacting to every draw down that I think is the end of the world. Biggest learnings. Test for worst case portfolio drawdown, size accordingly. Trade top strategies within that portfolio, cycle out worst performers every few months. Seems to be a winning recipe and am so excited to think about the next chapter in this journey I’ve been on for many many moons 😃

Read more →

StatOasis is calm, evidence-based algorithmic-trading education, founded by Ali Casey. Ali builds systematic trading strategies and teaches the workflow behind them: research, build, test, combine, deploy. He writes the Overfit newsletter, published since 2024, and runs the Algo Trading Masterclass.

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Products

  • Overfit - the newsletter
  • Algo Trading Masterclass ↗
  • StatOasis Community
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  • 36 Ways to Buy the Dip
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Reading & tools

  • Research
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  • Survive the Decade
  • Wall of Love

StatOasis

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