FDT IDE adds new project type for the ActionScript transpiler in Apache FlexJS
Good news, ActionScript community! The FDT IDE can now create projects that use the asjsc transpiler from Apache FlexJS 0.5. If you prefer an IDE over the command line, this will certainly be one of the easiest ways to get started transpiling ActionScript.

For full details, see the official announcement from the FDT team:

http://fdt.powerflasher.com/2015/12/flexjs-compiler-support/

I just gave it a try with the free version of FDT, and it was super easy to get started. I simply added Apache FlexJS 0.5 as an SDK, and then I created a new project using the "Web-JSC" template. Since it included some sample "Hello World" code, it was super easy to launch it in the browser right away! I made a few tweaks to the code and FDT showed all of the appropriate code hints. Great stuff!