What is the purpose of NinjaTrader.Vendor.dll?

[tcdouglas]

Please can someone explain the purpose of NinjaTrader.Vendor.dll? I can't find any mention of this dll in the NinjaTrader help.

I can see that third-party add-ons reference NinjaTrader.Vendor.dll instead of NinjaTrader.Custom.dll, and that Vendor.dll contains a 'duplicate' declaration of the Indicator base class with a reduced set of predefined indicators:

private NinjaTrader.NinjaScript.Indicators.CurrentDayOHL[] cacheCurrentDayOHL;
private NinjaTrader.NinjaScript.Indicators.EMA[] cacheEMA;
private NinjaTrader.NinjaScript.Indicators.LinReg[] cacheLinReg;
private NinjaTrader.NinjaScript.Indicators.SMA[] cacheSMA;
private NinjaTrader.NinjaScript.Indicators.SUM[] cacheSUM;
private NinjaTrader.NinjaScript.Indicators.Swing[] cacheSwing;
private NinjaTrader.NinjaScript.Indicators.OrderFlowCumula tiveDelta[] cacheOrderFlowCumulativeDelta;
private NinjaTrader.NinjaScript.Indicators.OrderFlowMarket DepthMap[] cacheOrderFlowMarketDepthMap;
private NinjaTrader.NinjaScript.Indicators.OrderFlowTradeD etector[] cacheOrderFlowTradeDetector;
private NinjaTrader.NinjaScript.Indicators.OrderFlowVWAP[] cacheOrderFlowVWAP;
private NinjaTrader.NinjaScript.Indicators.WisemanAlligato r[] cacheWisemanAlligator;
private NinjaTrader.NinjaScript.Indicators.WisemanAwesomeO scillator[] cacheWisemanAwesomeOscillator;
private NinjaTrader.NinjaScript.Indicators.WisemanFractal[] cacheWisemanFractal;
private NinjaTrader.NinjaScript.Indicators.WoodiesCCI[] cacheWoodiesCCI;
private NinjaTrader.NinjaScript.Indicators.WoodiesPivots[] cacheWoodiesPivots;

Why don't third-party vendors just reference NinjaTrader.Custom.dll in their add-ons?

[bltdavid]

That DLL contains the indicators that come with the platform
that are closed source.

The open source indicators you see in there (such as EMA,
Swing, etc) are 'duplicated' because they are being used by
those closed source indicators.

'Vendor' in this case refers to NinjaTrader itself and/or the
internal relationships that allow it to provide 3rd party closed
source indicators (such as Wiseman and Woodies) as a
standard part of the platform.