print a message when a key is pressed

enable subscribing to an interrupt and set up the PIC

end tasks when they trigger an exception

enable freeing of memory

add passing data to a syscall

use registers for passing data to system calls

add the ability to create multiple services and repair inter-service communication

add port IO syscalls

clean up syscall code

add basic cross-calling of service providers

organize services and their providers

enter usermode for user processes and start with some memory protection

first steps in services that can be run by the os

add basic kernel page management