msc not found

[ShalokShalom]

➜  mono-addins which mcs
/usr/bin/mcs

➜  mono-addins LC_ALL=C makepkg -si
==> Making package: mono-addins 1.1-1 (Sat Sep  2 13:41:29 CEST 2017)
==> Checking runtime dependencies...
==> Checking buildtime dependencies...
==> Retrieving sources...
  -> Found mono-addins-1.1.tar.gz
==> Validating source files with md5sums...
    mono-addins-1.1.tar.gz ... Passed
==> Extracting sources...
  -> Extracting mono-addins-1.1.tar.gz with bsdtar
==> Removing existing $pkgdir/ directory...
==> Starting build()...
I am going to run ./configure with no arguments - if you wish 
to pass any to it, please specify them on the ./autogen.sh command line.
Running aclocal -I .  ...
Running automake --gnu  ...
configure.ac:88: warning: omit leading './' from config file names such as './mono-addins.spec';
configure.ac:88: remake rules might be subtly broken otherwise
configure.ac:88: warning: omit leading './' from config file names such as './Mono.Addins/mono-addins.pc';
configure.ac:88: remake rules might be subtly broken otherwise
configure.ac:88: warning: omit leading './' from config file names such as './Mono.Addins.Gui/mono-addins-gui.pc';
configure.ac:88: remake rules might be subtly broken otherwise
configure.ac:88: warning: omit leading './' from config file names such as './Mono.Addins.Setup/mono-addins-setup.pc';
configure.ac:88: remake rules might be subtly broken otherwise
configure.ac:88: warning: omit leading './' from config file names such as './Mono.Addins.MSBuild/mono-addins-msbuild.pc';
configure.ac:88: remake rules might be subtly broken otherwise
configure.ac:88: warning: omit leading './' from config file names such as './Makefile';
configure.ac:88: remake rules might be subtly broken otherwise
configure.ac:88: warning: omit leading './' from config file names such as './policy.config';
configure.ac:88: remake rules might be subtly broken otherwise
configure.ac:88: warning: omit leading './' from config file names such as './Mono.Addins.Gui/Makefile';
configure.ac:88: remake rules might be subtly broken otherwise
configure.ac:88: warning: omit leading './' from config file names such as './Mono.Addins.Setup/Makefile';
configure.ac:88: remake rules might be subtly broken otherwise
configure.ac:88: warning: omit leading './' from config file names such as './Mono.Addins/Makefile';
configure.ac:88: remake rules might be subtly broken otherwise
configure.ac:88: warning: omit leading './' from config file names such as './Mono.Addins.CecilReflector/Makefile';
configure.ac:88: remake rules might be subtly broken otherwise
configure.ac:88: warning: omit leading './' from config file names such as './Mono.Addins.MSBuild/Makefile';
configure.ac:88: remake rules might be subtly broken otherwise
configure.ac:88: warning: omit leading './' from config file names such as './mautil/Makefile';
configure.ac:88: remake rules might be subtly broken otherwise
configure.ac:88: warning: omit leading './' from config file names such as './mautil/mautil';
configure.ac:88: remake rules might be subtly broken otherwise
configure.ac:88: warning: omit leading './' from config file names such as './docs/Makefile';
configure.ac:88: remake rules might be subtly broken otherwise
configure.ac:88: warning: omit leading './' from config file names such as './Test/HelloWorldExtension/Makefile';
configure.ac:88: remake rules might be subtly broken otherwise
configure.ac:88: warning: omit leading './' from config file names such as './Test/FileContentExtension/Makefile';
configure.ac:88: remake rules might be subtly broken otherwise
configure.ac:88: warning: omit leading './' from config file names such as './Test/UnitTests/Makefile';
configure.ac:88: remake rules might be subtly broken otherwise
configure.ac:88: warning: omit leading './' from config file names such as './Test/CommandExtension/Makefile';
configure.ac:88: remake rules might be subtly broken otherwise
configure.ac:88: warning: omit leading './' from config file names such as './Test/SystemInfoExtension/Makefile';
configure.ac:88: remake rules might be subtly broken otherwise
configure.ac:88: warning: omit leading './' from config file names such as './Test/FileExtender/Makefile';
configure.ac:88: remake rules might be subtly broken otherwise
configure.ac:88: warning: omit leading './' from config file names such as './Test/Makefile';
configure.ac:88: remake rules might be subtly broken otherwise
xbuild.include:59: warning: EXTRA_DIST multiply defined in condition TRUE ...
./Mono.Addins.CecilReflector/Makefile.am:8:   'xbuild.include' included from here
Makefile.include:30: ... 'EXTRA_DIST' previously defined here
./Mono.Addins.CecilReflector/Makefile.am:7:   'Makefile.include' included from here
xbuild.include:59: warning: EXTRA_DIST multiply defined in condition ENABLE_GUI ...
./Mono.Addins.Gui/Makefile.am:12:   'xbuild.include' included from here
Makefile.include:30: ... 'EXTRA_DIST' previously defined here
./Mono.Addins.Gui/Makefile.am:11:   'Makefile.include' included from here
xbuild.include:59: warning: EXTRA_DIST multiply defined in condition TRUE ...
./Mono.Addins.MSBuild/Makefile.am:10:   'xbuild.include' included from here
Makefile.include:30: ... 'EXTRA_DIST' previously defined here
./Mono.Addins.MSBuild/Makefile.am:9:   'Makefile.include' included from here
xbuild.include:59: warning: EXTRA_DIST multiply defined in condition TRUE ...
./Mono.Addins.Setup/Makefile.am:9:   'xbuild.include' included from here
Makefile.include:30: ... 'EXTRA_DIST' previously defined here
./Mono.Addins.Setup/Makefile.am:8:   'Makefile.include' included from here
xbuild.include:59: warning: EXTRA_DIST multiply defined in condition TRUE ...
./Mono.Addins/Makefile.am:10:   'xbuild.include' included from here
Makefile.include:30: ... 'EXTRA_DIST' previously defined here
./Mono.Addins/Makefile.am:9:   'Makefile.include' included from here
xbuild.include:59: warning: EXTRA_DIST multiply defined in condition TRUE ...
./mautil/Makefile.am:9:   'xbuild.include' included from here
Makefile.include:30: ... 'EXTRA_DIST' previously defined here
./mautil/Makefile.am:8:   'Makefile.include' included from here
Running autoconf ...
Running ./configure ...
checking for a BSD-compatible install... /usr/bin/install -c
checking whether build environment is sane... yes
checking for a thread-safe mkdir -p... /usr/bin/mkdir -p
checking for gawk... gawk
checking whether make sets $(MAKE)... yes
checking whether make supports nested variables... yes
checking whether UID '1000' is supported by ustar format... yes
checking whether GID '1001' is supported by ustar format... yes
checking how to create a ustar tar archive... gnutar
checking whether to enable maintainer-specific portions of Makefiles... yes
checking for pkg-config... /usr/bin/pkg-config
checking for gmcs... no
configure: error: mcs Not found
==> ERROR: A failure occurred in build().
    Aborting...

This is the build script is used: https://gist.github.com/ShalokShalom/ca5a1950aba64101bdeb99a1fada5596