Strategies

What a strategy is, how revisions work, and how to create your first one.

A strategy is a piece of Java code that reacts to market data and emits trading signals. Every save creates a new revision — strategies are versioned, and every backtest points at exactly one revision, so a result always names the exact code that produced it.

Create your first strategy

Open Strategies → New (or the “New” action on the Strategies card on the dashboard). The flow is a four-step wizard, and you can go back to any earlier step without losing what you entered.

1. Idea

Give the strategy a title and a description. The title identifies it across every future revision — letters, numbers, spaces, and . , _ / ( ) + & : - are allowed. The description is free text: what the strategy is trying to do and the reasoning behind it.

2. Generate

You don’t have to write Java by hand. This step hands you a ready-made prompt — built from the title and description you just entered plus a link to QTSurfer’s official strategy skill (the engine’s API, signal format, and authoring conventions) — and three ways to turn it into code:

• Open Codex or Open Claude Code — opens the assistant with the prompt copied to your clipboard, or use Copy prompt to paste it into any AI assistant yourself.
• Advanced mode — skip the assistant and write or paste Java directly.

The AI runs outside QTSurfer: generate the code there, then come back and paste it into the next step.

3. Paste code

Paste the generated Java into the editor. Load example fills in a small working reference strategy if you want to see the expected shape first — an EMA crossover:

import com.wualabs.qtsurfer.engine.strategy.*;
import com.wualabs.qtsurfer.engine.strategy.event.signal.InfoStrategySignal;
import com.wualabs.qtsurfer.engine.indicators.helpers.WindowTimeRTIndicator.WindowTime;
import com.wualabs.qtsurfer.engine.indicators.helpers.group.InstrumentGroupRTIndicator;
import com.wualabs.qtsurfer.engine.core.state.StateStore;

public class EmaCrossStrategy extends AbstractTickerStrategy {

    @Override
    protected void setupIndicators(InstrumentGroupRTIndicator indicators) {
        indicators
            .addPrice()
            .ema("fast", 20)
            .ema("slow", 50)
            .window("fast", WindowTime.s1, new CrossListener(indicators));
    }

    private class CrossListener extends AbstractWindowListener {
        public CrossListener(InstrumentGroupRTIndicator indicators) {
            super(EmaCrossStrategy.this, indicators);
        }

        @Override
        public void onChange(StateStore store, double prev, double actual) {
            double price = indicators.getValue("price");
            double fast = indicators.getValue("fast");
            double slow = indicators.getValue("slow");

            InfoStrategySignal signal = createInfoSignal();

            boolean wasBullish = store.is("bullish");
            boolean isBullish = fast > slow;

            if (isBullish && !wasBullish) {
                store.set("bullish");
                signal.set("_m", "position", "belowBar", "shape", "arrowUp",
                    "color", "#26a69a", "text", "BUY");
                emitBuy(price);
            } else if (!isBullish && wasBullish) {
                store.unset("bullish");
                signal.set("_m", "position", "aboveBar", "shape", "arrowDown",
                    "color", "#ef5350", "text", "SELL");
                emitSell(price);
            }

            emitSignal(signal);
        }
    }
}

4. Review

The strategy is only saved once the code validates and compiles. This step sends it to the backend compiler; a failed compile keeps you on this step with the error message and the offending line highlighted in the editor, so you can fix it and retry without losing your work.

After creation

• Revisions — editing a strategy again produces a new revision, never overwrites the old one. Every backtest and every marketplace listing points at a specific revision.
• Share — from your strategy list, Share opens the publishing flow for a revision: visibility, access model, and an optional price. See Marketplace.
• Reference copies — a strategy you picked up from the Marketplace is a read-only reference copy (no source, no edit/clone/new-revision) unless you bought a CODE listing — see Marketplace for the distinction.