Pulling mail 
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Branched 2087 revisions.                                                                               
Skipping build granite (already ran)
'mail' has prerequisites that need to be staged: granite
Skipping pull granite (already ran)
Skipping build granite (already ran)
Skipping stage granite (already ran)
Preparing to build mail 
Building mail 
cmake /root/parts/mail/src -DCMAKE_INSTALL_PREFIX= -DCMAKE_INSTALL_PREFIX=/usr
-- The C compiler identification is GNU 5.3.1
-- Check for working C compiler: /usr/bin/cc
-- Check for working C compiler: /usr/bin/cc -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- Icon cache will be updated
-- Desktop database will be updated
-- Found PkgConfig: /root/parts/mail/bin/pkg-config (found version "0.29.1") 
-- Found Vala: /usr/bin/valac  
-- checking for Vala version of 0.22.1
--   found Vala, version 0.30.1
-- Found vapigen: /usr/bin/vapigen
-- Unity launcher support: ON
-- Targeting WebKitGTK 2.4
-- GTK+ 3.12 support: ON
-- Vala fatal warnings: ON
-- Checking for modules 'granite;gthread-2.0;glib-2.0>=2.40.0;gio-2.0>=2.28.0;gtk+-3.0>=3.10.0;gee-0.8>=0.8.5;libcanberra>=0.28;sqlite3>=3.7.4;gmime-2.6>=2.6.17;libsecret-1>=0.11;libxml-2.0>=2.7.8;gcr-3>=3.10.1;gobject-introspection-1.0;unity;webkitgtk-3.0>=2.3.0'
--   No package 'granite' found
Traceback (most recent call last):
  File "/root/parts/mail/bin/pkg-config", line 60, in <module>
    main()
  File "/root/parts/mail/bin/pkg-config", line 56, in main
    run_pkg_config(args, env=real_env)
  File "/root/parts/mail/bin/pkg-config", line 11, in run_pkg_config
    check_call(['/usr/bin/pkg-config'] + args, env=env)
  File "/usr/lib/python3.5/subprocess.py", line 581, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['/usr/bin/pkg-config', '--exists', '--print-errors', '--short-errors', 'granite']' returned non-zero exit status 1
CMake Error at /usr/share/cmake-3.5/Modules/FindPkgConfig.cmake:367 (message):
  A required package was not found
Call Stack (most recent call first):
  /usr/share/cmake-3.5/Modules/FindPkgConfig.cmake:532 (_pkg_check_modules_internal)
  src/CMakeLists.txt:518 (pkg_check_modules)


-- Configuring incomplete, errors occurred!
See also "/root/parts/mail/build/CMakeFiles/CMakeOutput.log".
Command '['/bin/sh', '/tmp/tmp3fij6rsf', 'cmake',
'/root/parts/mail/src', '-DCMAKE_INSTALL_PREFIX=',
'-DCMAKE_INSTALL_PREFIX=/usr']' returned non-zero exit status 1