Capistrano local asset precompile

deploy_local_assets.rb

set :local_path, Dir.pwd

namespace :deploy do
  namespace :assets do

    desc 'Run asset procompilation locally'
    task :precompile_locally, :roles => :web, :except => {:no_release => true} do
      run_locally("bundle exec rake assets:precompile")
    end

    desc 'Copy procompiled assets to servers'
    task :copy_local_assets, :roles => :web, :except => {:no_release => true} do
      servers = find_servers_for_task(current_task)
      port_option = port ? " -e 'ssh -p #{port}' " : ''
      servers.each do |server|
        run_locally "rsync --recursive --times --rsh=ssh --compress --human-readable #{port_option} --progress public/assets #{user}@#{server}:#{latest_release}/public"
      end
    end

    desc 'Overridden by config/deploy_local_assets.rb.rb'
    task :precompile, :roles => :web, :except => {:no_release => true} do
      # dont precompile, we already did a local precompile
    end

    desc 'Overridden by config/deploy_local_assets.rb.rb'
    task :symlink do
      # dont symlink the asset directory from shared - we just put them in the release dir
    end

    desc 'Remove temporary files from local precompilation'
    task :clean_up_local_precompile, :roles => :web, :except => {:no_release => true} do
      run_locally("rm -rf public/assets/*")
    end

  end
end

before 'deploy:update', 'deploy:assets:precompile_locally'
after  'deploy:update', 'deploy:assets:copy_local_assets'
after  'deploy:assets:copy_local_assets', 'deploy:assets:clean_up_local_precompile'
on_rollback { find_and_execute_task 'deploy:assets:clean_up_local_precompile' }

And add
load 'config/deploy_local_assets'
to your Cap file