Free · B4 Signal API v1 · NinjaTrader 8

Build indicators that speak B4.

The free B4 Signal API, three ready-to-learn demo indicators and the B4 NinjaTrader 8 skill library for AI-assisted development. Everything you need to publish entry and confirmation signals the B4 way.

Download the free kit ↓Browse the repository

OnBarUpdate()

// reset, then publish for the current bar
b4BuySignal[0]  = false;
b4SellSignal[0] = false;
b4ConfirmationDirection[0] = 0;

if (B4UseEntrySignals) {
    b4BuySignal[0]  = CrossAbove(fast, slow, 1);
    b4SellSignal[0] = CrossBelow(fast, slow, 1);
}
if (B4UseConfirmations)
    b4ConfirmationDirection[0] =
        fast[0] > slow[0] ? 1 : -1;

B4 Signal API v1

Five members. One clear contract.

Add these members to any NinjaTrader 8 indicator and its signals can be read by B4 tools and by any other NinjaScript, exactly like built-in indicator series. The API publishes signals only; it never places orders.

MemberTypeMeaning

B4UseEntrySignalsbool settingTurns entry signals on or off (default on)

B4UseConfirmationsbool settingTurns the confirmation series on or off (default on)

B4BuySignalsSeries<bool>true only on the bar that produced a buy signal

B4SellSignalsSeries<bool>true only on the bar that produced a sell signal

B4ConfirmationDirectionsSeries<int>1 long bias, -1 short bias, 0 none, for the current bar

Pulse, then reset

Reset every bar to false / false / 0, then publish. A signal is true only on the bar it happened.

Exact names, exact attributes

Tools match by name. Keep the types, the settings group "B4 CoPilot Pro Integration" and the empty setters.

Signals, never orders

API indicators publish information only. Execution stays with a strategy or tool the trader controls.

Full API guide Copy-paste API block (.cs)

Free demo projects

Three indicators to learn from.

Simple, readable NinjaScript written from scratch, each with the B4 Signal API built in. Every signal-affecting value is an adjustable setting.

B4ApiDemoEmaCross.cs

EMA Cross

A fast EMA crossing a slow EMA publishes buy and sell signals; the confirmation series reports the trend side.

Settings: fast period, slow period
Confirmation: 1 while fast > slow, -1 while below

Download .cs

B4ApiDemoRsiReversal.cs

RSI Reversal

RSI climbing back out of oversold publishes a buy; falling back out of overbought publishes a sell.

Settings: period, smoothing, oversold, overbought, midline
Confirmation: RSI above or below the midline

Download .cs

B4ApiDemoDonchianBreakout.cs

Donchian Breakout

A close beyond the previous N-bar channel publishes a breakout signal in that direction.

Settings: channel period
Confirmation: direction of the most recent breakout

Download .cs

Download all three demos (.zip)

B4 NinjaTrader 8 skill library

Teach your AI assistant to build NT8 the right way.

Seven skills for Claude Code and compatible AI coding tools. Each one turns hard-won NinjaTrader 8 engineering practice into a procedure, with templates and checklists.

Indicator Foundations

nt8-indicator-foundations

Lifecycle states, plots, Series<T>, properties, bar guards, Calculate modes, anti-repaint and hot-path performance, plus a starter template.

Use when: creating or editing any NT8 indicator.

B4 Signal API

nt8-b4-signal-api

Add the five-member B4 Signal API v1 to any indicator, with a copy-paste block and a test checklist.

Use when: an indicator should publish B4 entry and confirmation signals.

Adjustable Parameters

nt8-adjustable-parameters

No hard-wired trading values. Turn every threshold, period and offset into a setting without changing behavior.

Use when: writing new code or removing magic numbers.

Build Verification

nt8-build-verification

Eight verification gates, real compiles, an error database and an honest build report. No "should work".

Use when: finishing any change, or a compile fails.

Drawing & Rendering

nt8-drawing-and-rendering

Draw.* overloads and tags, when to move to OnRender with SharpDX, resource lifetime and keeping visuals out of logic.

Use when: adding arrows, zones, labels or custom visuals.

Order Flow & Data

nt8-order-flow-and-data

OnMarketData trade classification, Tick Replay, Level II depth, multiple series and keeping real versus estimated order flow honest.

Use when: building footprint, delta, CVD, profile or DOM tools.

Safe Deployment

nt8-safe-deployment

Back up, deploy only when flat, understand the automatic compile, reload charts and keep a rollback path.

Use when: installing or updating NinjaScript on a live platform.

Download the skill library (.zip)

New · B4 Indicator AI

Build smarter. Learn faster. Research with AI.

Browse the B4 Indicators repository, build your own indicators with an AI coding assistant, and follow what is coming next. B4 proprietary technology stays protected.

Available now

Repository

A GitHub-style browser for every public project: the B4 Signal API, the demo indicators and the skill library, with source, documentation and downloads.

Open the repository

Available now

Build with B4

Describe an indicator in plain language; your AI coding assistant builds and verifies it with the skill library and the public API.

Open the Studio

Preview

Ask and Test with B4

An assistant grounded in data you authorize, and reproducible research on your own ideas. In development; not yet available.

Learn more

New · Free developer edition

B4 CoPilot Dev. Your tools, our execution shell.

A stripped-down, free edition of the B4 execution shell for developers. No B4 filters and no order-flow signals: you plug in your own signal, filter and exit tools through the B4 Signal API and test them in simulation.

Plug in by name: a signal tool, up to three filter tools and an exit tool, each a normal NT8 indicator with the B4 Signal API.
Seed pack: blank signal, filter and exit templates with the wiring done. Replace the example logic with yours.
Built-in order handling: stop and target in ticks, trading hours, max trades per day, exit on opposite signal.
Simulation accounts only: Sim101, Playback and Strategy Analyzer. It never places an order on a live account.

Get the free seed pack Browse the seeds

B4 CoPilot Dev itself ships as a protected NinjaTrader import, coming soon. Join with the form and you will be emailed when it is ready. It contains no B4 proprietary logic, and B4 CoPilot Pro remains a separate product.

How your tools connect

Signal tool: B4BuySignals / B4SellSignals pulses are the entries.
Filter tools: B4ConfirmationDirections must agree with the signal, or not oppose it.
Exit tool: its sell pulse exits a long, its buy pulse exits a short.
Type each class name into the B4 CoPilot Dev settings. That is all.

B4 Signals memberships · Black Friday 2026

Ready for the full B4 toolkit?

The developer kit is free. B4 memberships add the complete B4 indicator suite, B4 CoPilot Pro, the NinjaTrader 8 toolkit and the full B4 AMP education program.

Monthly

$150 / month

The full B4 toolkit plus B4 Tape, B4 L2 DOM Pro and B4 Scanner, billed monthly.

Buy now ↗

Quarterly

$397 / 3 months

Save $53 versus paying monthly. Everything in Monthly.

Buy now ↗

Best value

Annual

$897 / year

Best value: save $903 versus paying monthly. Everything in Monthly.

Buy now ↗

One-Time

$1,200 one-time

A single payment for the current B4 membership products. Not a subscription.

Buy now ↗

Compare memberships on B4Signals.com ↗B4 Funding evaluations ↗

Secure checkout on members.b4signals.com. For educational purposes only. Not trading advice. Trading involves substantial risk.

Install

Up and running in minutes.

Demo indicators (NinjaTrader 8)

Make sure you are flat, ideally with the market closed.
Copy the .cs file into Documents\NinjaTrader 8\bin\Custom\Indicators\.
Open the NinjaScript Editor and compile (F5); check for errors.
Add "B4 API Demo - ..." to a chart. The B4 settings sit under B4 CoPilot Pro Integration.

Skill library (Claude Code)

Unzip the library.
Copy a skill folder into %USERPROFILE%\.claude\skills\ for personal use, or .claude\skills\ inside a project.
Ask for NinjaTrader 8 work as usual; the matching skill loads automatically from its description.

The demos place no orders, read no account data and write no files. They are learning material, not trading systems. Community projects built with this kit are third-party work unless B4 reviews and supports them.