For joint effort/contribution, these steps are necessary to create a workable (minimum) build environment
as of 6.2-release
curl-7.55.1 get files from FTP, Gopher, HTTP or HTTPS servers
git-2.14.2 GIT - Tree History Storage Tool
ruby-2.3.5 object oriented script language with threads
ruby23-bundler-1.15.1 ruby application dependency manager
vmm-firmware-1.10.2p4 firmware binary images for vmm(4) driver
You might feel like rbenv or something, or just straight on:
ln -sf /usr/local/bin/ruby23 /usr/local/bin/ruby
ln -sf /usr/local/bin/erb23 /usr/local/bin/erb
ln -sf /usr/local/bin/irb23 /usr/local/bin/irb
ln -sf /usr/local/bin/rdoc23 /usr/local/bin/rdoc
ln -sf /usr/local/bin/ri23 /usr/local/bin/ri
ln -sf /usr/local/bin/rake23 /usr/local/bin/rake
ln -sf /usr/local/bin/gem23 /usr/local/bin/gem
ln -sf /usr/local/bin/bundler23 /usr/local/bin/bundler
ln -sf /usr/local/bin/bundle23 /usr/local/bin/bundle
git clone https://github.com/double-p/vagrant-openbsd.git
cd vagrant-openbsd
bundle install # install (many) GEM dependecies
rake build # build vagrant + plugin
bundle exec vagrant plugin install pkg/vagrant-openbsd-0.1.0.gem
bundle exec vagrant plugin list
bundle install --binstubs