error: command ['cmake', '-D', 'CMAKE_BUILD_TYPE=RelWithDebInfo', '-G', 'Ninja', '.'] failed

I have just installed yotta manually on my mac, using homebrew. I followed the getting started guide exactly. I was working through the blinky first application tutorial, but I get the following log:

Unknown-88-63-df-a3-2e-e9:blinky georgeedwards$ yotta build info: generate for target: nordic-nrf51822-armcc 1.0.0 at /Users/georgeedwards/Desktop/blinky/yotta_targets/nordic-nrf51822-armcc warning: subdirectory "test" of blinky 0.0.0 at /Users/georgeedwards/Desktop/blinky was ignored because it doesn't appear to contain any source files

ERROR: the arm toolchain program armcc could not be found.

Note that the armcc toolchain is not available for Max OS X.

**************************************************************************
CMake Error at /Users/georgeedwards/Desktop/blinky/yotta_targets/mbed-armcc/CMake/toolchain.cmake:42 (message):
  missing program prevents build
Call Stack (most recent call first):
  /Users/georgeedwards/Desktop/blinky/yotta_targets/mbed-armcc/CMake/toolchain.cmake:47 (arm_toolchain_program_notfound)
  toolchain.cmake:8 (include)
  /usr/local/Cellar/cmake/3.5.2/share/cmake/Modules/CMakeDetermineSystem.cmake:98 (include)
  CMakeLists.txt:83 (project)

CMake Error: CMAKE_C_COMPILER not set, after EnableLanguage
CMake Error: CMAKE_CXX_COMPILER not set, after EnableLanguage
-- Configuring incomplete, errors occurred!
error: command ['cmake', '-D', 'CMAKE_BUILD_TYPE=RelWithDebInfo', '-G', 'Ninja', '.'] failed

I have aded to my project:

Unknown-88-63-df-a3-2e-e9:blinky georgeedwards$ yotta target nordic-nrf51822-armcc 1.0.0 mbed-armcc 1.1.0

I followed the installation instructions for both windows and osx on my pc and mac, and both times I have faced the same issue. Not sure if this is an issue with the getting started guide, yotta, the nordic nrf51-DK, or most likely, my interpretation, but it is weird I have faced this using two separate machines and separate steps. I would really appreciate some guidance to get this up and running.

Similarly, If I try with the GCC target, I get this output:

Unknown-88-63-df-a3-2e-e9:blinky georgeedwards$ yotta build
info: generate for target: nordic-nrf51822-32k-gcc 0.1.3 at /Users/georgeedwards/Desktop/blinky/yotta_targets/nordic-nrf51822-32k-gcc
warning: subdirectory "test" of blinky 0.0.0 at /Users/georgeedwards/Desktop/blinky was ignored because it doesn't appear to contain any source files
GCC version is: 5.3.1
omit frame pointer for bootloader startup asm
suppressing warnings from nrf51-sdk
-- The ASM compiler identification is GNU
-- Found assembler: /usr/local/bin/arm-none-eabi-gcc
CMake Error at /Users/georgeedwards/Desktop/blinky/yotta_modules/mbed-hal-nrf51822-mcu/CMakeLists.txt:94 (message):
  Missing PLATFORM_SPECIFIC_HAL_LIB

-- Configuring incomplete, errors occurred!
See also "/Users/georgeedwards/Desktop/blinky/build/nordic-nrf51822-32k-gcc/CMakeFiles/CMakeOutput.log".
error: command ['cmake', '-D', 'CMAKE_BUILD_TYPE=RelWithDebInfo', '-G', 'Ninja', '.'] failed

It does however work with nrf51dk-gcc ...

ARMmbed / yotta

error: command ['cmake', '-D', 'CMAKE_BUILD_TYPE=RelWithDebInfo', '-G', 'Ninja', '.'] failed #771