chruby vs SDKMAN!

chruby is a free, MIT-licensed shell utility for changing the Ruby version used in a session. Selecting a Ruby updates PATH and sets GEM_HOME and GEM_PATH for that installation. It can match installed Ruby names fuzzily and uses the system Ruby when no selection is made. Optional automatic switching checks the current and parent directories for a .ruby-version file. chruby supports bash 3 or later and zsh on Linux and macOS. Installation instructions cover a release tarball, Homebrew, Arch Linux AUR, Fedora Copr, and FreeBSD ports. Additional Ruby implementations can be installed with ruby-install or ruby-build. The project provides guidance for integrations including Capistrano, Chef, Cron, Emacs, Pow, Puppet, Sudo, Vim, and Fish. Releases are PGP signed, with verification instructions, and the codebase is described as about 100 lines with tests.

SDKMAN! is a command-line interface and API for managing Software Development Kits in the JVM ecosystem. It supports languages and tools including Java, Scala, Kotlin, Groovy, Ant, Gradle, Grails, Maven, SBT, Spark, Spring Boot, and Vert.x. From the CLI, users can install, uninstall, list, inspect, switch, upgrade, and set default SDK versions. A project can record its versions in an .sdkmanrc file, with automatic switching available when entering its directory. Java distributions are obtained through the Foojay DISCO API. SDKMAN! works on macOS and Linux; Windows use requires WSL or MSYS with MinGW, since it does not run natively there. Cygwin is no longer supported. The installer requires curl, zip, and unzip, and works with Bash and ZSH. Its CI mode answers prompts, disables colored output, and turns off self-updates. SDKMAN! is free, open source, and Apache 2.0 licensed. Security updates are provided only for the latest released CLI version. The project says Go, Rust, Node.js, Python, and Ruby toolchains are outside its intended scope.