Bundler: You Must Use Bundler 2 Or Greater With This Lockfile
Answer : I had a similar experience. Here's how I solved it Display a list of all your local gems for the bundler gem gem list bundler N/B : The command above is for rbenv version manager, the one for rvm might be different This will display the versions of the bundler gem installed locally bundler (2.1.4, default: 1.17.2) if you don't have bundler version 2 installed locally, then run gem install bundler OR gem install bundler -v 2.1.4 if you have bundler version 2 already installed locally or just installed it, then you need to simply install an update for RubyGems Package Manager locally. To do this, run gem update --system And then finally run bundle update --bundler For Docker projects in Ruby on Rails If you're experiencing this issue when trying to build your application using Docker, simply do this: Delete the Gemfile.lock file Please don't create it again by running bundle install . Run your docker build or docker-compose build comm...