memoize ruby_version_jruby?
memoize ruby_version_jruby?

rhomobile/heroku-buildpack-ruby,ndbroadbent/heroku-buildpack-turbo-sprockets,bskyb-commerce/help-heroku-buildpack,travis-ci/heroku-buildpack-ruby,wakermahmud/heroku-buildpack-jekyll,donnykurnia/heroku-buildpack-ruby,daltonrenaldo/heroku-buildpack-ruby,sgnpa/heroku-buildpack-cas,Scalingo/ruby-buildpack,sky-uk/ruby-buildpack,progrium/heroku-buildpack-ruby,rstacruz/heroku-buildpack-middleman,mattmanning/heroku-buildpack-ruby-jekyll,millie/heroku-buildpack-ruby-with-pdftk,reesio/heroku-buildpack-ruby,DigitalInnovation/heroku-buildpack-mslabs,wolfoo2931/heroku-buildpack-ruby-2a352ae,jonseaberg/heroku-buildpack-turbo-sprockets,gls1/heroku-buildpack-ruby-pdftk,sky-uk/ruby-buildpack,redhotvengeance/heroku-buildpack-deep-thought,icelab/heroku-buildpack-ruby,codykrieger/heroku-buildpack-jekyll,jglascoe/heroku-buildpack-ruby-jekyll,zunda/heroku-buildpack-ruby,Nedomas/heroku-buildpack-ruby-minus-node-with-node-paths,derrek/heroku-buildpack-ruby,ChefSteps/heroku-buildpack-ruby,adaptivelab/heroku-buildpack-adaptivelab-website-2,AdStage/heroku-buildpack-ruby,tpope/heroku-buildpack-ruby-tpope,simonnordberg/heroku-buildpack-ruby,joshco/heroku-buildpack-ruby,scottatron/moc-buildpack,packetmonkey/heroku-buildpack-ruby,daltonrenaldo/heroku-buildpack-ruby,sky-uk/ruby-buildpack,takii/db2rubybuildpack,fgbreel/heroku-buildpack-ruby,fcruxen/ruby-buildpack,KoanHealth/heroku-buildpack-marvin-setup,hausdorff/heroku-buildpack-ruby-jekyll,stolt45/heroku-buildpack-ruby-with-sqlite3,mattmanning/heroku-buildpack-ruby-jekyll,zoomer/heroku-buildpack-ruby-bower,swipesense/heroku-buildpack-ruby,WilliamDenniss/heroku-buildpack-ruby-imagemagick,dleavitt/heroku-buildpack-ruby,recursecenter/heroku-buildpack-ruby,crdschurch/heroku-buildpack-ruby,Jonty/ruby-buildpack,hellojustin/heroku-buildpack-custom-ruby,lemurheavy/heroku-buildpack-ruby,Jonty/ruby-buildpack,ltrademark/heroku-buildpack-ruby,hone/heroku-buildpack-ruby,pkgr/buildpack-ruby-precise-old,righi/instacart-heroku-buildpack,space150/heroku-buildpack-ruby,nicholasmott/heroku-buildpack-octopress,gbenedict/heroku-buildpack-ruby,moneyadviceservice/heroku-buildpack-ruby-bowndler,CPPWind/ruby-buildpack,thirdprestige/heroku-buildpack-ruby,shuber/heroku-buildpack-ruby,dtao/deft-buildpack-ruby,CPPWind/ruby-buildpack,wolfoo2931/heroku-buildpack-ruby-2a352ae,thewebguy/heroku-buildpack-ruby-ffmpeg-libsndfile,bskyb-commerce/ruby-buildpack,musicglue/heroku-buildpack-ruby,thewebguy/heroku-buildpack-ruby-ffmpeg-libsndfile,codykrieger/heroku-buildpack-jekyll,d-reinhold/cf-buildpack-ruby,mrhenry/heroku-buildpack-ruby,leonardykris/mos-ruby-buildpack,ericboehs/heroku-buildpack-ruby,heroku/heroku-buildpack-ruby,jcamenisch/heroku-buildpack-rgeo,firmhouse/heroku-buildpack-ruby-freetds,CPPWind/ruby-buildpack,jgable/buildpack-ruby-rack-setup-tasks,sky-uk/ruby-buildpack,sky-uk/help-heroku-buildpack,jasonlevens/heroku-buildpack-ruby,meskyanichi/heroku-buildpack-middleman,makifund/heroku-buildpack-ruby,tomwolfe/heroku-buildpack-gsl-ruby,bwaite-jaroop/heroku-buildpack-ruby,qstream/heroku-buildpack-ruby,mattwalters/heroku-buildpack-ruby,travis-ci/heroku-buildpack-ruby,samfrench/heroku-buildpack-ruby,darron/heroku-buildpack-ruby-jekyll,teodor-pripoae/heroku-buildpack-ruby,pcincalifornia/wdc-heroku-buildpack-middleman,pkgr/heroku-buildpack-ruby,WilliamDenniss/heroku-buildpack-ruby-imagemagick,recursecenter/heroku-buildpack-ruby,schu/buildpack-testing,jonasoberschweiber/heroku-buildpack-ruby,tpope/heroku-buildpack-ruby-tpope,ibmdb/db2rubybuildpack,pkgr/heroku-buildpack-ruby,orlando/heroku-buildpack-ruby,mperejda/heroku-buildpack-ruby,ekaranto/rails4-bluemix-buildpack,pcincalifornia/wdc-heroku-buildpack-middleman,progrium/heroku-buildpack-ruby,cloudn/buildpack-ruby,sgnpa/heroku-buildpack-cas,orlando/heroku-buildpack-ruby,derrek/heroku-buildpack-ruby,CPPWind/ruby-buildpack,progrium/heroku-buildpack-ruby,catalyzeio/buildpack-ruby,beydogan/ruby-buildpack,ericroberts/heroku-buildpack-ruby,michaelphines/alexa-nest,centresource/heroku-buildpack-turbo-sprockets-pmp-ffm,lemurheavy/heroku-buildpack-ruby,DouglasAllen/heroku-buildpack-ruby,mintybit/heroku-buildpack-ruby,12spokes/heroku-buildpack-ruby-imagemagick,pavgup/heroku-buildpack-ruby-lateslugignore,mperejda/heroku-buildpack-ruby,0x00evil/heroku-buildpack-ruby,allomov/fat-free-heroku-buildpack-ruby,lyoshenka/heroku-buildpack-ruby-jekyll,DigitalInnovation/heroku-buildpack-mslabs,stolt45/heroku-buildpack-ruby-with-sqlite3,righi/instacart-heroku-buildpack,ericboehs/heroku-buildpack-ruby,Altoros/ruby-buildpack,firmhouse/heroku-buildpack-ruby-freetds,hellojustin/heroku-buildpack-custom-ruby,zidekmat/buildpack-ruby,mattwalters/heroku-buildpack-ruby,AdStage/heroku-buildpack-ruby,ejholmes/heroku-buildpack-middleman,thirdprestige/heroku-buildpack-ruby,takii/heroku-buildpack-ruby,jumptvs/BP_Ruby,ruby/heroku-buildpack-www-ruby-lang,HYPERHYPER/heroku-buildpack-ruby,dtao/teeny-buildpack,rvizza/heroku-buildpack-gsl-ruby,ericroberts/heroku-buildpack-ruby,atmos/heroku-buildpack-ruby,iamjarvo/ruby-buildpack,jgarber/heroku-buildpack-ruby-octopress,swipesense/heroku-buildpack-ruby,cloudControl/buildpack-ruby,Numerico/heroku-buildpack-ruby,ndbroadbent/heroku-buildpack-turbo-sprockets,phusion/heroku-buildpack-ruby,takii/db2rubybuildpack,Jonty/ruby-buildpack,cloudn/buildpack-ruby,WilliamDenniss/heroku-buildpack-ruby-imagemagick,schu/buildpack-testing,electricobjects/heroku-buildpack-ruby,pkgr/buildpack-ruby-precise-old,catalyzeio/buildpack-ruby,takii/db2rubybuildpack,trumaker/heroku-buildpack-turbo-sprockets,rowanoulton/heroku-buildpack-ruby,cloudControl/buildpack-ruby,hixi/heroku-buildpack-ruby,Altoros/ruby-buildpack,anay/buildpack-ruby-with-oracle-jdk,zunda/heroku-buildpack-ruby,jumptvs/BP_Ruby,amaltson/heroku-buildpack-ruby,rvizza/heroku-buildpack-gsl-ruby,electricobjects/heroku-buildpack-ruby,ablease/custom-buildpack,bskyb-commerce/ruby-buildpack,awebneck/heroku-buildpack-canvas,fcruxen/ruby-buildpack,Genius/heroku-buildpack-ruby,cloudfoundry/ruby-buildpack,iamjarvo/ruby-buildpack,jgarber/heroku-buildpack-ruby-octopress,hpcloud/ruby-buildpack,blueapron/heroku-buildpack-ruby,Genius/heroku-buildpack-ruby,ascot21/heroku-buildpack-turbo-sprockets,centresource/heroku-buildpack-turbo-sprockets-pmp-ffm,tdenovan/heroku-buildpack-ruby,packetmonkey/heroku-buildpack-ruby,markaschneider/heroku-buildpack-ruby-ffmpeg-sox,dlorson/gentle-buildpack,jumptvs/BP_Ruby,travis-ci/heroku-buildpack-ruby,cmaggard/heroku-buildpack-turbo-sprockets,jgable/buildpack-ruby-rack-setup-tasks,donnykurnia/heroku-buildpack-ruby,bskyb-commerce/ruby-buildpack,davidjrice/heroku-buildpack-couchbase-ruby,leonardykris/mos-ruby-buildpack,zoomer/heroku-buildpack-ruby-bower,thirdprestige/heroku-buildpack-ruby,ekaranto/rails4-bluemix-buildpack,hone/heroku-buildpack-ruby,aarongray/heroku-buildpack-ruby,ekaranto/rails4-bluemix-buildpack,ablease/custom-buildpack,cordata/heroku-buildpack-ruby,andycroll/heroku-buildpack-jekyll,sanemat/heroku-buildpack-ruby-tachikoma,cloudfoundry/ruby-buildpack,instacart/heroku-buildpack-ruby,firmhouse/heroku-buildpack-ruby-freetds,dlorson/gentle-buildpack,awebneck/heroku-buildpack-canvas,bwaite-jaroop/heroku-buildpack-ruby,nthj/heroku-buildpack-mirror,sstelfox/buildpack-ruby,bskyb-commerce/help-heroku-buildpack,Numerico/heroku-buildpack-ruby,Dim25/heroku-buildpack-ruby-GSL,blueapron/heroku-buildpack-ruby,musicglue/heroku-buildpack-ruby,cloudn/buildpack-ruby,gls1/heroku-buildpack-ruby-pdftk-new,diasks2/heroku-buildpack-mecab,hatofmonkeys/ruby-testing-buildpack,HYPERHYPER/heroku-buildpack-ruby,jumptvs/BP_Ruby,gls1/heroku-buildpack-ruby-pdftk-new,DyegoCosta/heroku-buildpack-ruby,Jonty/ruby-buildpack,pietrop/heroku-buildpack-ruby,davidjrice/heroku-buildpack-couchbase-ruby,reesio/heroku-buildpack-ruby,jasonlevens/heroku-buildpack-ruby,ascot21/heroku-buildpack-turbo-sprockets,vhx/heroku-buildpack,ibmdb/db2rubybuildpack,zidekmat/buildpack-ruby,tomwolfe/heroku-buildpack-gsl-ruby,pilotcreative/heroku-buildpack-ruby,shuber/heroku-buildpack-ruby,lemurheavy/heroku-buildpack-ruby,ablease/custom-buildpack,hpcloud/ruby-buildpack,jayshreeanand/heroku-buildpack-ruby,dieze/heroku-buildpack-ruby-hooks,qstream/heroku-buildpack-ruby,dleavitt/heroku-buildpack-ruby,gbenedict/heroku-buildpack-ruby,pkgr/buildpack-ruby-precise-old,barakav/heroku-buildpack-ruby,Altoros/ruby-buildpack,cloudn/buildpack-ruby,davidjrice/heroku-buildpack-couchbase-ruby,instacart/heroku-buildpack-ruby,rhomobile/heroku-buildpack-ruby,brightbytes/heroku-buildpack-ruby-without-assets-precompile,ActiveState/heroku-buildpack-ruby,qnyp/heroku-buildpack-ruby-bower,orenyk/heroku-buildpack-ruby,sanemat/heroku-buildpack-ruby-tachikoma,tenjikinc/heroku-buildpack-ruby,dtao/teeny-buildpack,adaptivelab/heroku-buildpack-adaptivelab-website-2,iamjarvo/ruby-buildpack,beydogan/ruby-buildpack,Scalingo/ruby-buildpack,amaltson/heroku-buildpack-ruby,KoanHealth/heroku-buildpack-marvin-setup,fcruxen/ruby-buildpack,hpcloud/ruby-buildpack,jonseaberg/heroku-buildpack-turbo-sprockets,dieze/heroku-buildpack-ruby-hooks,vhx/heroku-buildpack,ActiveState/heroku-buildpack-ruby,ltrademark/heroku-buildpack-ruby,phusion/heroku-buildpack-ruby,anay/buildpack-ruby-with-oracle-jdk,aarongray/heroku-buildpack-ruby,rstacruz/heroku-buildpack-middleman,barakav/heroku-buildpack-ruby,ekaranto/rails4-bluemix-buildpack,jeremyvdw/heroku-buildpack-ruby-jekyll,Git-Host/prelang-buildpack,Nedomas/heroku-buildpack-ruby-minus-node-with-node-paths,mrhenry/heroku-buildpack-ruby,atmos/heroku-buildpack-ruby,jglascoe/heroku-buildpack-ruby-jekyll,gls1/heroku-buildpack-ruby-pdftk,guidance-guarantee-programme/heroku-buildpack-princexml-old,ejholmes/heroku-buildpack-middleman,stefansundin/heroku-buildpack-ruby,dtao/deft-buildpack-ruby,12spokes/heroku-buildpack-ruby-imagemagick,orenyk/heroku-buildpack-ruby,pavgup/heroku-buildpack-ruby-lateslugignore,michaelphines/alexa-nest,teodor-pripoae/heroku-buildpack-ruby,cloudfoundry/ruby-buildpack,rowanoulton/heroku-buildpack-ruby,ilpoldo/heroku-buildpack-ruby,jcamenisch/heroku-buildpack-rgeo,iamjarvo/ruby-buildpack,d-reinhold/cf-buildpack-ruby,mintybit/heroku-buildpack-ruby,ChefSteps/heroku-buildpack-ruby,cmaggard/heroku-buildpack-turbo-sprockets,ilpoldo/heroku-buildpack-ruby,tdenovan/heroku-buildpack-ruby,Dim25/heroku-buildpack-ruby-GSL,brightbytes/heroku-buildpack-ruby-without-assets-precompile,cloudfoundry/ruby-buildpack,ablease/custom-buildpack,hpcloud/ruby-buildpack,sanemat/heroku-buildpack-ruby-tachikoma,space150/heroku-buildpack-ruby,icelab/heroku-buildpack-ruby,sstelfox/buildpack-ruby,hatofmonkeys/ruby-testing-buildpack,Git-Host/prelang-buildpack,ibmdb/db2rubybuildpack,guidance-guarantee-programme/heroku-buildpack-princexml-old,schu/heroku-buildpack-ruby,engineyard/heroku-buildpack-ruby,Micka33/heroku-buildpack-ruby-liblua,scottatron/moc-buildpack,hpcloud/heroku-buildpack-ruby,hpcloud/heroku-buildpack-ruby,atmos/heroku-buildpack-ruby,schu/heroku-buildpack-ruby,lyoshenka/heroku-buildpack-ruby-jekyll,andycroll/heroku-buildpack-jekyll,nicholasmott/heroku-buildpack-octopress,allomov/fat-free-heroku-buildpack-ruby,pietrop/heroku-buildpack-ruby,bellycard/heroku-buildpack-ruby,samfrench/heroku-buildpack-ruby,sgnpa/heroku-buildpack-cas,jonasoberschweiber/heroku-buildpack-ruby,meskyanichi/heroku-buildpack-middleman,phusion/heroku-buildpack-ruby,moneyadviceservice/heroku-buildpack-ruby-bowndler,trumaker/heroku-buildpack-turbo-sprockets,heroku/heroku-buildpack-ruby,d-reinhold/cf-buildpack-ruby,qnyp/heroku-buildpack-ruby-bower,redhotvengeance/heroku-buildpack-deep-thought,markaschneider/heroku-buildpack-ruby-ffmpeg-sox,jgarber/heroku-buildpack-ruby-octopress,bellycard/heroku-buildpack-ruby,erintherad/heroku-buildpack-ruby,jeremyvdw/heroku-buildpack-ruby-jekyll,DyegoCosta/heroku-buildpack-ruby,fcruxen/ruby-buildpack,cloudfoundry/ruby-buildpack,diasks2/heroku-buildpack-mecab,Altoros/ruby-buildpack,sky-uk/help-heroku-buildpack,bskyb-commerce/ruby-buildpack,darron/heroku-buildpack-ruby-jekyll,pilotcreative/heroku-buildpack-ruby,stefansundin/heroku-buildpack-ruby,takii/db2rubybuildpack,crdschurch/heroku-buildpack-ruby,tenjikinc/heroku-buildpack-ruby,nthj/heroku-buildpack-mirror,Numerico/heroku-buildpack-ruby,0x00evil/heroku-buildpack-ruby,nicholasmott/heroku-buildpack-octopress,cordata/heroku-buildpack-ruby,hatofmonkeys/ruby-testing-buildpack,takii/heroku-buildpack-ruby,DouglasAllen/heroku-buildpack-ruby,centresource/heroku-buildpack-turbo-sprockets-pmp-ffm,erintherad/heroku-buildpack-ruby,wakermahmud/heroku-buildpack-jekyll,engineyard/heroku-buildpack-ruby,makifund/heroku-buildpack-ruby,joshco/heroku-buildpack-ruby,pavgup/heroku-buildpack-ruby-lateslugignore,Micka33/heroku-buildpack-ruby-liblua,simonnordberg/heroku-buildpack-ruby,AdStage/heroku-buildpack-ruby,jayshreeanand/heroku-buildpack-ruby,fgbreel/heroku-buildpack-ruby,millie/heroku-buildpack-ruby-with-pdftk,hausdorff/heroku-buildpack-ruby-jekyll,hixi/heroku-buildpack-ruby