This tool stores seed phrases in a local directory (~/.grdn), and allows you to organize them hierarchically. Seeds are AES-128 encrypted with a password (the same one for all seeds), and stored in a tree structure. This allows organization by purpose, location, application, wallet, or anything else you can think of. They can be nested as deeply as you want. This tool is not recommended for security-critical usecases.
$ gem install grdn
To see usage information, run grdn help.
The gem is available as open source under the terms of the MIT License.