Hello
Following the instructions on for installing Metacello into Squeak 6.0a-17230 (= most recent trunk version as of today) runs fine.
Regards Hannes
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// [1] https://github.com/dalehenrich/metacello-work
Copy/paste the code below into a workspace and 'do it'
"Get the Metacello configuration (for Squeak users)" Installer gemsource project: 'metacello'; addPackage: 'ConfigurationOfMetacello'; install.
"Bootstrap Metacello Preview, using mcz files (#'previewBootstrap' symbolic version" ((Smalltalk at: #ConfigurationOfMetacello) project version: #'previewBootstrap') load.
"Load the Preview version of Metacello from GitHub" (Smalltalk at: #Metacello) new configuration: 'MetacelloPreview'; version: #stable; repository: 'github://dalehenrich/metacello-work:configuration'; load.
"Now load latest version of Metacello" (Smalltalk at: #Metacello) new baseline: 'Metacello'; repository: 'github://dalehenrich/metacello-work:master/repository'; get. (Smalltalk at: #Metacello) new baseline: 'Metacello'; repository: 'github://dalehenrich/metacello-work:master/repository'; load.