PSL1GHT is a lightweight PlayStation 3 homebrew SDK, provided as a temporary way to compile user apps to run from the XMB using the open-source PS3 toolchains available.
PSL1GHT has moved to HACKERCHANNEL. This fork may or may not serve as my development branch, and may or may not be updated at all anymore. So go there instead for "official" releases.
A GCC toolchain that supports the PowerPC 64bit architecture is required to build PSL1GHT and its samples. It also requires the toolchain to provide a full newlib environment; at the moment only two toolchains do so:
The SDK also includes a few standalone tools to help compilation. A host gcc is required to build raw2h, and Python 2.x is required to run make_fself.py
Run make install in the psl1ght directory to build it all, and make sure to set the environment variable $PSL1GHT to the folder where you wish to install it to, for example...
cd /path/to/psl1ght.git export PSL1GHT=/path/to/psl1ght.git/build make make install
... for a local build of it. Ensure that $PSL1GHT is set when you are building any of the examples or other apps that use PSL1GHT.
At the moment, PSL1GHT has basic libc support, with stdout debugging, file access, etc. It doesn't have any way to access the screen/graphics. You can call lv2 syscalls and do some fun stuff with that, but it doesn't link to PS3 dynamic libraries yet which is where all the exciting functionality comes in.