FREE!
This is a lightweight IDE which is simple to use and fast.
Actually using your own tools to develop always makes the tools better. And our BASIC was written in C using our MakeItC IDE. That BASIC code base is over a dozen files and 3000 lines of code.
We don't believe in forcing a new text editor down your throat, so you can chose the one you like, or use the latest Notepad++ that we will install.
The make process is automated, so as long as your include paths cover all your files, you point it at the main file and it should find all the pieces. This will create both a .hex file for download and .bin file for mBed. We include a downloader for NXP using their ISP.