After creating a new project amber.js is undefined. You can recreate this issue by creating a new Amber project adding console.log(Amber) to the bottom of main.js
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Amber CLI (amberframework.org) - v0.11.3
Crystal 0.27.0 [c9d1eef8f] (2018-11-01)
Default target: x86_64-unknown-linux-gnu