need help with rookie mistake

[G. Branden Robinson]

I'm making a rookie mistake here, but I can't figure out which one.

ncurses seems not to be exposing the opaque functions.

cc -D_DEFAULT_SOURCE -D_XOPEN_SOURCE=600 simple.c -o simple -lncurses -ltinfo
simple.c: In function ‘main’:
simple.c:21:6: warning: implicit declaration of function ‘is_cbreak’; did you 
mean ‘nocbreak’? [-Wimplicit-function-declaration]
   21 |  if (is_cbreak())
      |      ^~~~~~~~~
      |      nocbreak
simple.c:23:6: warning: implicit declaration of function ‘is_echo’ 
[-Wimplicit-function-declaration]
   23 |  if (is_echo())
      |      ^~~~~~~
simple.c:25:6: warning: implicit declaration of function ‘is_nl’ 
[-Wimplicit-function-declaration]
   25 |  if (is_nl())
      |      ^~~~~
simple.c:27:6: warning: implicit declaration of function ‘is_raw’; did you mean 
‘is_pad’? [-Wimplicit-function-declaration]
   27 |  if (is_raw())
      |      ^~~~~~
      |      is_pad
/usr/bin/ld: /tmp/branden/cc4pIV6R.o: in function `main':
simple.c:(.text+0x51): undefined reference to `is_cbreak'
/usr/bin/ld: simple.c:(.text+0x7a): undefined reference to `is_echo'
/usr/bin/ld: simple.c:(.text+0xa3): undefined reference to `is_nl'
/usr/bin/ld: simple.c:(.text+0xcc): undefined reference to `is_raw'
collect2: error: ld returned 1 exit status
make: *** [Makefile:14: simple] Error 1

Source and Makefile attached.

Regards,
Branden

simple.c
Description: simple.c

Makefile
Description: Makefile

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