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netci.groovy Jenkins: Fix daily builds of ARM by building on Windows 8.1 for now. Jun 30, 2018


Join the chat at Licensed under the MIT License

ChakraCore is the core part of Chakra, the high-performance JavaScript engine that powers Microsoft Edge and Windows applications written in HTML/CSS/JS. ChakraCore supports Just-in-time (JIT) compilation of JavaScript for x86/x64/ARM, garbage collection, and a wide range of the latest JavaScript features. ChakraCore also supports the JavaScript Runtime (JSRT) APIs, which allows you to easily embed ChakraCore in your applications.

You can stay up-to-date on progress by following the MSEdge developer blog.

Build Status

Debug Test Release
Windows (x64) x64debug x64test x64release
Windows (x86) x86debug x86test x86release
Windows (ARM) armdebug armtest armrelease
Ubuntu 16.04 (x64)[a] linux_a_debug linux_a_test linux_a_release
Ubuntu 16.04 (x64)[s] linux_s_debug linux_s_test linux_s_release
Ubuntu 16.04 (x64)[s][n] * linux_sn_test *
OS X 10.9 (x64)[a] osx_a_debug osx_a_test osx_a_release
OS X 10.9 (x64)[s][n] * osx_sn_test *

[a] Static | [s] Shared | [n] NoJIT | * Omitted

Above is a table of our rolling build status. We run additional builds on a daily basis. See Build Status for the status of all builds and additional details.


If you believe you have found a security issue in ChakraCore, please share it with us privately following the guidance at the Microsoft Security TechCenter. Reporting it via this channel helps minimize risk to projects built with ChakraCore.


Building ChakraCore

You can build ChakraCore on Windows 7 SP1 or above, and Windows Server 2008 R2 or above, with either Visual Studio 2015 or 2017 with C++ support installed. Once you have Visual Studio installed:

  • Clone ChakraCore through git clone
  • Open Build\Chakra.Core.sln in Visual Studio
  • Build Solution

More details in Building ChakraCore.

Alternatively, see Getting ChakraCore binaries for pre-built ChakraCore binaries.

Using ChakraCore

Once built, you have a few options for how you can use ChakraCore:

  • The most basic is to test the engine is running correctly with the ch.exe binary. This app is a lightweight hosting of JSRT that you can use to run small applications. After building, you can find this binary in:
    • Build\VcBuild\bin\${platform}_${configuration}
    • (e.g. Build\VcBuild\bin\x64_debug)
  • You can embed ChakraCore in your applications - see documentation and samples.
  • Finally, you can also use ChakraCore as the JavaScript engine in Node. You can learn more by reading how to use Chakra as Node's JS engine

A note about using ChakraCore: ChakraCore is the foundational JavaScript engine, but it does not include the external APIs that make up the modern JavaScript development experience. For example, DOM APIs like document.write() are additional APIs that are not available by default and would need to be provided. For debugging, you may instead want to use print().


Contributions to ChakraCore are welcome. Here is how you can contribute to ChakraCore:

This project has adopted the Microsoft Open Source Code of Conduct. For more information see the Code of Conduct FAQ or contact with any additional questions or comments.

Please refer to Contribution Guidelines for more details.


Code licensed under the MIT License.


For details on our planned features and future direction please refer to our Roadmap.

Contact Us

If you have questions about ChakraCore, or you would like to reach out to us about an issue you're having or for development advice as you work on a ChakraCore issue, you can reach us as follows:

  • Open an issue and prefix the issue title with [Question]. See Question tag for already-opened questions.
  • Discuss ChakraCore with the team and the community on our Gitter Channel.
  • You can also start private messages with individual ChakraCore developers via Gitter.