Exclude jekyll-feed in development environment?

How did you reach to this conclusion?
Are you developing on Windows?

A few:

  • If you’re on Windows, ensure that you’ve listed   gem 'wdm' in your Gemfile.
  • Use the --incremental switch (shorthand:-I) to process only those files that change:
    bundle exec jekyll serve -I
    
    Now, when you make changes to a particular “post” or “page”, only those and their layouts / includes are “re-processed”. The feed will still be generated but the total build time will be much lesser.
  • You can always disable a plugin by commenting it out in the _config.yml
    plugins:
    # - jekyll-feed
    - jekyll-sitemap
    
    and uncomment before commiting changes.
  • You can maintain two separate config files if the above is tiresome. For example, a regular _config.yml for production builds on GitHub Pages and the other named a _config_dev.yml for local builds.
    Then simply use the latter as following:
    bundle exec jekyll serve --config _config_dev.yml
    

Note: For either of the last two options to work you’ve to ensure the following:

  • you’re not using a “theme” that has listed jekyll-feed as its dependency / runtime_dependency.
  • you’ve not listed jekyll-feed in the :jekyll_plugins group in your Gemfile.