Development environment with nix-shell: Difference between revisions

If you already have a nix package definition of you project it's easy: Just use <code>nix-shell</code> instead of <code>nix-build</code> and you will end up in a bash shell that reproduce the build environment of your package. You can also override[https://nixos.org/nixpkgs/manual/#sec-pkg-override] your package in a <code>shell.nix</code> file to add test and coverage dependencies, that are not necessary for the actual build of the package, but that you want for your development environment.

But, if you don't (or you don't want to) have a package definition you can still use a nix-shell to provide a reproducible development environment. To do so, you have to create a <code>shell.nix</code> file at root of your repository. For example, if you want to have Ruby 2.3 and not the one of your system you can write:

One of the limitation of nix-shell is that you can't use an other shell then bash. Hopefully there is Direnv [[https://direnv.net/]] with the support of Nix[[https://github.com/direnv/direnv/wiki/Nix]] to overcome this limitation. Also Direnv provides some nice features like loading the environment automatically when you enter your project directory and show the loaded variables to you (explicit is always better;-)).

This happens due to a specialty in nix: <code>ld</code> is wrapped in a shell script which refuses to link against files not residing in the nix store, to ensure purity of builds. Obviously this is not useful when building locally, for example in your home directory. To disable this behavior simply set