The following features of ES5 cannot be shimmed.
Using Object.defineProperty if you define a non-enumerable property on an object then for..in loops over that object will behave correctly in modern browsers but enumerate over that property in legacy browsers.
This means that code that works in modern browsers, breaks in legacy browsers.
There a times when you need to build something from the nix unstable channel. For example the master contains a new package you need, but the next nixpkgs release is somewhere in the future, and you need this package now. In this guide I want to show how to install packages from unstable by using nix-env. Furthermore I hope to give a basic understanding of the channels concept.
A channel is a set of expressions which includes severall build, installation and configuration instructions for packages, services and the system itself. The repository normaly used here is nixpkgs. It is developed at https://github.com/NixOS/nixpkgs.
The unstable channel is a copy of the NixOS/nixpkgs master. It is pulled from github once in a while and will be available from a mirror under https://nixos.org/channels/nixpkgs-unstable. Since NixOS uses half-anual released stable channels, some changes (especially new f
