mikutter PKGBUILD error

makepkg -si
==> Making package: mikutter 3.8.7-1 (Tue 14 May 2019 03:59:20 PM EEST)
==> Checking runtime dependencies...
==> Checking buildtime dependencies...
==> Retrieving sources...
  -> Found mikutter.3.8.7.tar.gz
  -> Found mikutter.desktop
  -> Found config.patch
==> Validating source files with md5sums...
    mikutter.3.8.7.tar.gz ... Passed
    mikutter.desktop ... Passed
    config.patch ... Passed
==> Extracting sources...
  -> Extracting mikutter.3.8.7.tar.gz with bsdtar
==> Starting prepare()...
patching file core/config.rb
==> Removing existing $pkgdir/ directory...
==> Starting build()...
Ignoring do_sqlite3-0.10.17 because its extensions are not built. Try: gem pristine do_sqlite3 --version 0.10.17
Ignoring eventmachine-1.0.9.1 because its extensions are not built. Try: gem pristine eventmachine --version 1.0.9.1
Ignoring json-1.8.6 because its extensions are not built. Try: gem pristine json --version 1.8.6
Ignoring nokogiri-1.8.4 because its extensions are not built. Try: gem pristine nokogiri --version 1.8.4
Ignoring thin-1.7.2 because its extensions are not built. Try: gem pristine thin --version 1.7.2
Successfully installed rake-12.3.2
1 gem installed
Ignoring do_sqlite3-0.10.17 because its extensions are not built. Try: gem pristine do_sqlite3 --version 0.10.17
Ignoring eventmachine-1.0.9.1 because its extensions are not built. Try: gem pristine eventmachine --version 1.0.9.1
Ignoring json-1.8.6 because its extensions are not built. Try: gem pristine json --version 1.8.6
Ignoring nokogiri-1.8.4 because its extensions are not built. Try: gem pristine nokogiri --version 1.8.4
Ignoring thin-1.7.2 because its extensions are not built. Try: gem pristine thin --version 1.7.2
Fetching gem metadata from https://rubygems.org/...........
Resolving dependencies...
Using public_suffix 3.0.3
Using addressable 2.5.2
Using native-package-installer 1.0.7
Using pkg-config 1.3.7
Using glib2 3.3.2
Fetching atk 3.3.2
Installing atk 3.3.2 with native extensions
Gem::Ext::BuildError: ERROR: Failed to build gem native extension.

    current directory: /home/pant/git/arch/mikutter/src/mikutter/vendor/bundle/ruby/2.6.0/gems/atk-3.3.2/dependency-check
rake RUBYARCHDIR\=/home/pant/git/arch/mikutter/src/mikutter/vendor/bundle/ruby/2.6.0/extensions/x86_64-linux/2.6.0/atk-3.3.2
RUBYLIBDIR\=/home/pant/git/arch/mikutter/src/mikutter/vendor/bundle/ruby/2.6.0/extensions/x86_64-linux/2.6.0/atk-3.3.2
/usr/lib/ruby/2.6.0/rubygems.rb:283:in `find_spec_for_exe': can't find gem rake (>= 0.a) with executable rake (Gem::GemNotFoundException)
	from /usr/lib/ruby/2.6.0/rubygems.rb:302:in `activate_bin_path'
	from /home/pant//gems/bin/rake:23:in `<main>'

rake failed, exit code 1

Gem files will remain installed in /home/pant/git/arch/mikutter/src/mikutter/vendor/bundle/ruby/2.6.0/gems/atk-3.3.2 for inspection.
Results logged to /home/pant/git/arch/mikutter/src/mikutter/vendor/bundle/ruby/2.6.0/extensions/x86_64-linux/2.6.0/atk-3.3.2/gem_make.out

An error occurred while installing atk (3.3.2), and Bundler cannot continue.
Make sure that `gem install atk -v '3.3.2' --source 'https://rubygems.org/'` succeeds before bundling.

In Gemfile:
  gtk2 was resolved to 3.3.2, which depends on
    atk
==> ERROR: A failure occurred in build().
    Aborting...