# kerl > Build and install Erlang/OTP instances with ease. > More information: . - Build and install an Erlang/OTP version in a directory: `kerl build-install {{28.0}} {{28.0}} {{path/to/installation_directory}}/{{28.0}}` - Activate an Erlang/OTP installation: `. {{path/to/installation}}/activate` - Deactivate the current Erlang/OTP installation: `kerl_deactivate` - List all available Erlang/OTP releases: `kerl list releases` - List installed Erlang/OTP builds: `kerl list installations`