Riff buildpacks with provides/requires interface

idea.toml

[[order]]
  [[order.group]]
  id = "cloudfoundry/openjdk-jre"
  version = "1.0.0"
  optional = true

  [[order.group]]
  id = "cloudfoundry/jvm-application"
  version = "1.0.0"
  optional = true

  [[order.group]]
  id = "cloudfoundry/nodejs"
  version = "1.0.0"
  optional = true

  [[order.group]]
  id = "cloudfoundry/npm"
  version = "1.0.0"
  optional = true

  [[order.group]]
  id = "cloudfoundry/riff-function"
  version = "1.0.0"

  [[order.group]]
  id = "projectriff/java-function-buildpack"
  version = "1.0.0"
  optional = true

  [[order.group]]
  id = "projectriff/node-function-buildpack"
  version = "1.0.0"
  optional = true


# cloudfoundry/java buildplan
  [[provides]]
  name = "openjdk-jre"

# cloudfoundry/jvm-application buildplan
  [[provides]]
  name = "jvm-application"

# cloudfoundry/nodejs buildplan
  [[provides]]
  name = "node"

# cloudfoundry/npm buildplan
  [[provides]]
  name = "node_modules"

# cloudfoundry/riff-function buildplan
  [[requires]]
  name = "openjdk-jre"

  [[requires]]
  name = "jvm-application"

  # I think this buildpack could look for any matching language requirements it finds and provide the interface for riff
  [[or.requires]]
  name = "node"

  [[or.requires]]
  name = "node_modules"

  [[provides]]
  name = "riff-java-function" # it detects it'll be java and RIFF=1 or riff.toml w/e
  stuff_from_riff_toml = "something"

  [[or.provides]]
  name = "riff-node-function" 
  function_uri = "/workspace/custom.js" # from riff.toml or package.json

# projectriff/java-function-buildpack buildplan
  [[requires]]
  name = "riff-java-function"

# projectriff/node-function-buildpack buildplan
  [[requires]]
  name = "riff-node-function"