-lib_kernel_SRC += lib/kernel/list.c # Doubly-linked lists.
-lib_kernel_SRC += lib/kernel/bitmap.c # Bitmaps.
-lib_kernel_SRC += lib/kernel/hash.c # Hash tables.
-lib_kernel_SRC += lib/kernel/console.c # printf(), putchar().
+lib/kernel_SRC = lib/kernel/debug.c # Debug helpers.
+lib/kernel_SRC += lib/kernel/list.c # Doubly-linked lists.
+lib/kernel_SRC += lib/kernel/bitmap.c # Bitmaps.
+lib/kernel_SRC += lib/kernel/hash.c # Hash tables.
+lib/kernel_SRC += lib/kernel/console.c # printf(), putchar().
+
+# User process code.
+userprog_SRC = userprog/process.c # Process loading.
+userprog_SRC += userprog/pagedir.c # Page directories.
+userprog_SRC += userprog/exception.c # User exception handler.
+userprog_SRC += userprog/syscall.c # System call handler.
+userprog_SRC += userprog/gdt.c # GDT initialization.
+userprog_SRC += userprog/tss.c # TSS management.
+
+# No virtual memory code yet.
+#vm_SRC = vm/file.c # Some file.