Need help with CUPS installation on Mikrotik RBM33G with OpenWRT.
Can't find any work distributive.
I need CUPS becouse only CUPS can manipulate with printing documents images (size, contrast, rotation)
I'd recommend that you install a USB drive as CUPS will need to spool documents, and potentially rasterized. A microSD would be another option, though the USB "sticks" are a little more robust. Then again a few GB of microSD is relatively inexpensive these days when it fails.
There have been several posts on the forums here around CUPS that may lead you to success
Edit: Adding to what slh stated below, RAM may be an issue as well. I recall my HP printers failing miserably with their original memory even with the less demanding documents of around 10 years ago, not being functional until boosted to the roughly 256 MB that they could accommodate.
Rendering postscript is a pretty ressource intensive task (CPU and RAM, especially if the target printer doesn't speak postscript natively), it usually makes more sense not to use CUPS but p910nd instead (which leaves the rendering to the client CPU and just passes the data through to the printer); your router might just make the cut, but not spooling on the internal flash, as suggested by jeff, is strongly recommended.