YantraJS (Machine in Sanskrit)

Please visit GitHub repo at YantraJS


Yantra (Machine in Sanskrit) is a Managed JavaScript Engine for .NET Standard written completely in C#.


Name Package
YantraJS (With CSX Module Support) NuGet
YantraJS.Core (Compiler) NuGet
YantraJS.ExpressionCompiler (IL Compiler) NuGet
Yantra JS.ModuleExtensions (Fluent interface for module registration) Nuget


  1. Compiles JavaScript to .Net Assembly
  2. Strict Mode Only JavaScript*
  3. Arrow functions
  4. Classes
  5. Class members
  6. Enhanced object literals
  7. Template strings and tagged templates
  8. Destructuring
  9. let const
  10. Map, Set, WeakMap, WeakSet
  11. Symbols
  12. Subclassable built-ins
  13. Binary and Octal literals
  14. Module support
  15. Null coalesce
  16. Optional property chain identifier?.[], identifier?.(, identifier?.identifier
  17. Rest, Default and Spread Parameters
  18. Generators, iterators, for..of
  19. Async/Await
  20. Optional parameters
  21. Tail call optimization
  22. Many ES5 + ES6 features
  23. CommonJS & ES6 Module Support
  24. Easily marshal CLR Object to JavaScript and other way around
  25. CSX Module support
  26. Mixed module system, YantraJS supports require and import.

* Most JavaScript today is available in strict mode, we do not feel any need to support non strict mode as modules are strict by default.

Mixed modules

Currently YantraJS supports Both CommonJS and ES modules without any extra work, with little trick, module resolution is node like, it does not take .js extension into account. We are trying to make a workaround and we will update the product soon. Module loader loads module asynchronously, so import will work without any extra effort. However, require will run AsyncPump to wait till the module is loaded correctly, this may lead to some deadlocks.

Mixed Modules Roadmap

  1. Detect the loading order, first check if the same named file exists, if yes, load it, allow auto appending extension in the configuration, so module loader can load corresponding files accordingly.
  2. Create correct algorithm to resolve module name to support loading of CSX module in the mix. YantraJS supports loading module independent of the implementation. We can support other languages like python, php in the YantraJS. This is only possible to load modules without extension.


  1. Introduction
  2. Expression Compiler
  3. JavaScript Engine


We recommend using Github Discussion on this repository for any question regarding this product.

Special Thanks

  1. We are thankful to authors of Jurassic (we have incorporated number parser, promise and some unit tests from Jurassic.) https://github.com/paulbartrum/jurassic
  2. We are thankful to authors of EsprimaDotNet, we initially built prototype over EsprimaDotNet, but we chose to build our parser/scanner from scratch to support token spans. https://github.com/sebastienros/esprima-dotnet
  3. We are thankful to author of ILPack (we have incorporated saving IL to Assembly from this library.) https://github.com/Lokad/ILPack

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