BreadcrumbsOnRails::JsonLd provides a custom builder for BreadcrumbsOnRails.

Pass builder: BreadcrumbsOnRails::JsonLd::Builder option to render_breadcrumbs and enclose them with script type="application/ld+json" tag as follows:

<script type="application/ld+json">
  <%= render_breadcrumbs builder: BreadcrumbsOnRails::JsonLd::Builder %>
</script>

Add this line to your application's Gemfile:

gem 'breadcrumbs_on_rails-json_ld'

And then execute:

$ bundle

Or install it yourself as:

$ gem install breadcrumbs_on_rails-json_ld

The gem is available as open source under the terms of the MIT License.