Usage of ~ (tilde) changed in Ruby or Rails?

Usage of ~ (tilde) changed in Ruby or Rails?
I am migrating some code from Rails 4 to Rails 5.

My current environment is:

Rails 5.2.0

ruby 2.5.1p57 (2018-03-29 revision 63029) [x86_64-linux]

In my previous Rails 4 environment during initialization when environment.rb is being loaded I could require a file and in that file I had

require ‘~/app/models/ralph_lib/ralph_sql’

and the file would load.

Now, when I invoke webrick, I get the error

/home/mydomain/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bootsnap-1.3.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:32:in `require’: cannot load such file – ~/app/models/ralph_lib/ralph_sql (LoadError)

If, instead, I use

require ‘/home/mydomain/app/models/ralph_lib/ralph_sql’

or

require_relative ‘…/app/models/ralph_lib/ralph_sql’

then ralph.sql loads successfuly

Am I overlooking some initialization in order to get tilde to work?

Ralph Shnelvar