ActionScript and MXML in Visual Studio Code

  • An extension for Microsoft's free editor, Visual Studio Code
  • Supports both Adobe AIR/Flash and Apache FlexJS workflows
  • Runs everywhere — including Windows, macOS, and Linux
  • Open source and supported by the community

Install VSCode Extension

Screenshot of NextGen ActionScript extension for Visual Studio Code

Code Intelligence

Enjoy the comforts of a fully-fledged ActionScript and MXML development environment.

  • Completion of types and members
  • Automatic imports of classes
  • Function parameter hints
  • Find all references
  • Ctrl+click jump to symbol
  • Search all symbol names in the workspace
Screenshot of IntelliSense
Screenshot of debugger stopped at a breakpoint


A debugger with all the bells and whistles that supports many runtimes.

  • Debug SWFs in Adobe AIR and Flash Player
  • Debug Apache FlexJS apps running in web browsers
  • Add breakpoints to ActionScript or MXML
  • Pause, step in/out/over, restart, and stop
  • See trace() calls in the debug console
  • Navigate the function call stack
  • Inspect an object's variables
  • Automatically stop at uncaught exceptions

Cross-platform, Cross-runtime

Build and debug on more platforms than most commercial ActionScript IDEs.

  • Runs on Windows, macOS and... yes, even Linux
  • Transpile to JavaScript with Apache FlexJS or build SWF files for Adobe AIR and Flash Player
  • Use the asconfigc utility for more consistent builds — share the exact same settings on the command line and Visual Studio Code
Microsoft Windows, Linux, Apple macOS, Apache FlexJS, Adobe Flash Player, and Adobe AIR logos
Photo of Harbs
I've switched over to VS Code already for most of my FlexJS development. Between the improvements to VS Code itself and your extension, things are getting better and better!
Harbs, Apache FlexJS contributor
Screenshot of search for NextGen ActionScript extension


To install the extension, open up Visual Studio Code and follow these quick steps:

  1. Open the Extensions view.
  2. Search for NextGen ActionScript.
  3. Click the Install button.

To configure an SDK, see the complete installation instructions for details.

A big thank you to the following sponsors for their generous support: