Add a nix dotfile target.

Makefile

@@ -5,12 +5,12 @@ STOWOPTS=-target $(HOME) -d $(PWD)
 DOTGITCONFIG=~/.gitconfig
 DOTPROFILE=~/.profile
 
-.PHONY: mosh common emacs git ruby haskell perl tmux vim zsh list home osx linux ws
+.PHONY: mosh common emacs git ruby haskell perl tmux vim zsh list home osx linux ws nix
 
 home: $(DOTGITCONFIG) $(DOTPROFILE)
 	$(DOTDEE) $(DOTPROFILE)
 
-ws: common mosh git ruby haskell perl tmux vim zsh home
+ws: common emacs nix mosh git ruby haskell perl tmux vim zsh home
 
 all: home
 
@@ -64,3 +64,6 @@ haskell:
 
 perl:
 	$(STOW) $(STOWOPTS) perl
+
+nix:
+	$(STOW) $(STOWOPTS) nix

nix/.profile.d/20-functions-nix.sh

@@ -0,0 +1,8 @@
+# nix/.profile.d/20-functions-nix.sh
+mk_nix_shell()
+{
+  cabal2nix --sha256="0" . \
+    | perl -0777 -p -e 's/{.+}:/{ haskellPackages ? (import <nixpkgs> {}).haskellPackages }:/s' \
+    | sed -E -e 's/(cabal\.mkDerivation)/with haskellPackages; \1/' -e 'sXsha256 = "0";Xsrc = "./.";X' \
+          > shell.nix;
+}

nix/.profile.d/99-final-nix.sh

@@ -0,0 +1,8 @@
+# nix.profile.d/99-final-nix.sh
+
+# The nix installer put something like this into the .profile.
+# BAD INSTALLER NO COOKIE!
+if [ -e ${HOME}/.nix-profile/etc/profile.d/nix.sh ]; then
+    . ${HOME}/.nix-profile/etc/profile.d/nix.sh;
+    export NIX_PATH=${HOME}/Developer/github.com/NixOS/nixpkgs:nixpkgs=${HOME}/Developer/github.com/NixOS/nixpkgs
+fi