Over on his Outside The Box blog, Owen Wengerd has started a tutorial on how to write BRX programs for Briscad using Linux:
The next order of business was to build and load a BRX module. I started by installing Code::Blocks, an open source cross platform C/C++ IDE that can be used in both Windows and Linux. The IDE installed fine, but then things got interesting.
Read it all at BRX on Linux: Getting Started.