A language for people and AI

Your trading rules.
Written clearly.

Flowscript is ftw.trade's language for trading strategies. It reads market data, calculates signals and defines when a strategy acts.

Write it yourself or with your AI. Backtest on real history, inspect each decision, then start on paper.

Learn in five minutes Language reference

The guides and reference are public. No account needed.

crossover.flowPaper strategy

Flowscript

uses { bars: "^1", paper: "^1" }
const close = bars.close(market, interval);
const fast = ema(close, 12);
const slow = ema(close, 26);
when (crossover(fast, slow) && !inPosition()) { paper.buy({ quote: 100 }); }
when (crossunder(fast, slow) && inPosition()) { paper.sell({}); }
metric("fast", fast);
metric("slow", slow);

Two moving averages. Buy on a cross above; sell on a cross below. Use a spot price feed to try this example.

Read it line by line

01 / INPUT

Read the market

Closing prices arrive as a series: one value for each completed bar.

02 / SIGNAL

Describe the condition

Built-in indicators calculate the averages. A crossing becomes a signal.

03 / ACTION

Say when to act

when fires as a condition turns true. Metrics show the values behind the decision.

From stream to strategy

See the moment your rules take over.

Data keeps arriving. Your strategy waits for a completed bar, checks its rules, then acts or waits.

Interactive illustration

01 Receive data

02 Close the bar

Bar complete

Many incoming records. One completed bar.

03 Evaluate rules

Flowscript

Update fast & slow

crossover(fast, slow)

!inPosition()

Cross above · no position

The same rules as the example above.

04 Act or wait

Paper buyBoth conditions are truepaper.buy({ quote: 100 })

A paper buy needs both a cross above and no position.

Spot prices collect into market bars.

Illustrated events, not live data. Each cycle is an independent example on closed bars.

Start with the idea. Learn the details.

A short guide, then as deep as you need.

Follow the introduction from top to bottom, or go straight to the part you need.

START HERE

Flowscript in five minutes

Flowscript is a language for writing trading rules. Read a complete strategy, understand each line, then check it, backtest it and run it on paper in ftw.trade.

Values, series and na

The rules of Flowscript on one page: values and series, na, expressions, functions, folds, enums and match, phases and libraries.

Triggers and orders

When a strategy acts (when, while and the combinators) and every order it can place on spot, perps, liquidity and protocols.

Indicators and models

The indicators built into Flowscript, sessions and VWAP, market profile, and trained models that fit the same way in a backtest and live.

Modules and imports

A strategy's uses line names what it reads and does. Every module (market data, books, venues, protocols, std contracts and your own libraries) with the line that imports it and a working example.

Tests and risk limits

Write tests that prove a strategy buys the move it should and holds still when it should, and an invariants block that refuses entries once it loses too much.

Full language reference

Where to find every Flowscript function, rule and error code, and the module catalog, in full.

From reading to running

Try your first strategy.

Open the editor on ftw.trade, or connect your AI. Check the code, backtest it and run on paper before choosing to use real funds.

Build your first strategy Connect your AI Flowscript skill for agents

Your trading rules.Written clearly.