Write the indicator you actually want.

What you get

• 126 functions: moving averages, dispersion, correlation and beta, drawdown, Sharpe and Sortino, RSI and ATR, crossings and state helpers
• Multi-line expressions with `let` bindings, so an idea can be built in steps instead of one unreadable line
• The same formula works in three places: plotted on the chart, as a screener condition, and as a computed column in a sheet
• Series for open, high, low, close, volume and returns, referenced by name
• Errors point at the expression rather than failing silently, so a wrong formula is visible instead of plausible

Why this is usually paid for

Custom indicators normally mean learning a vendor’s scripting language, and the useful parts of it — alerts on your own script, more than a couple on one chart, publishing — tend to sit on paid tiers.

A formula is a smaller idea than a language: no compilation step, no plot declarations, no boilerplate. Most of what people write scripts for is one expression, and that is what this is for.

How to use it

1. 1

   Start from what you would say out loud

   Most custom indicators are a sentence: "volume relative to its own twenty-bar average", or "how far price is from VWAP in ATRs". Write the sentence first, then translate it — `volume / sma(volume, 20)` and `(close - vwap()) / atr(14)` respectively.

2. 2

   Build it in steps with `let`

   A long single line is hard to check and harder to fix. Bind the parts — `let dist = close - vwap()`, `let unit = atr(14)`, then `dist / unit` — and each piece can be read on its own.

3. 3

   Plot it before you trust it

   Put the formula on the chart and look at it across a range you already understand. A normalisation error usually shows up immediately as a line that never leaves zero or never comes back to it.

4. 4

   Then screen with the same expression

   Once the formula reads correctly on one instrument, it can filter the whole venue. That is the point of it being one expression in three places: the thing you validated is the thing that scans.

Questions

Also free