Linux x86_64 (64-bit) is a Unix-like and mostly POSIX-compliant computer operating system (OS) assembled under the model of free and open-source software development and distribution. Using host OS (Mac OS X or Linux 64-bit) you can build native application for Linux x86_64 platform.
For more detailed information please visit vendor site.
Examples are listed from Linux x86_64 development platform repository:
; Latest stable version [env:latest_stable] platform = linux_x86_64 board = ... ; Custom stable version [env:custom_stable] platform = email@example.com board = ...
[env:upstream_develop] platform = https://github.com/platformio/platform-linux_x86_64.git board = ...
GCC Toolchain for Linux x86_64 machines