diff --git a/update-completion-links.zsh b/update-completion-links.zsh
index 80f4c33..12a6102 100755
--- a/update-completion-links.zsh
+++ b/update-completion-links.zsh
@@ -11,7 +11,7 @@ for completion in $zsh_completions/src/_*; do
   # Remove existing completion file if it exists.
   [ -f $symlink ] && rm $symlink
   # Check if the command exists on the PATH.
-  if which ${name:1} &> /dev/null; then
+  if command -v ${name:1} &> /dev/null; then
     # Symlink the completion for the existing command.
     [ `uname` = Darwin ] && \
       ln -s $completion $symlink || ln -sr $completion $symlink
diff --git a/zshenv b/zshenv
index 43ef38b..1ec0d82 100644
--- a/zshenv
+++ b/zshenv
@@ -37,7 +37,7 @@ export CCACHE_CONFIGPATH=$HOME/.config/ccache
 export CCACHE_DIR=$HOME/.cache/ccache
 
 # Add default CMake generator
-which ninja &> /dev/null && \
+command -v ninja &> /dev/null && \
   export CMAKE_GENERATOR=Ninja
 
 # Remove duplicates from environment variables
@@ -47,8 +47,12 @@ typeset -U MANPATH;   export MANPATH
 typeset -U INFOPATH;  export INFOPATH
 
 # Set default editor.
-which vim &> /dev/null && \
-  export EDITOR=`which vim`
+if command -v nvim &> /dev/null; then
+  export EDITOR=`command -v nvim`
+elif command -v vim &> /dev/null; then
+  export EDITOR=`command -v vim`
+fi
+export GIT_EDITOR=$EDITOR
 
 # Use ~/.local for pip installs on macOS
 [ "`uname`" = "Darwin" ] && export PYTHONUSERBASE=$HOME/.local
@@ -77,24 +81,24 @@ export PYLINTHOME=~/.local/share/pylint
 export VIRTUAL_ENV_DISABLE_PROMPT=1
 
 # If pinentry-curses exists, use it for lastpass-cli
-which pinentry-curses &> /dev/null && \
+command -v pinentry-curses &> /dev/null && \
   export LPASS_PINENTRY=pinentry-curses
 
 # Teach these some XDG Base Directory Spec manners
 export IPYTHONDIR=$HOME/.config/ipython
-which cargo &> /dev/null && \
+command -v cargo &> /dev/null && \
   export CARGO_HOME=$HOME/.local/share/cargo
-if which ccache &> /dev/null; then
+if command -v ccache &> /dev/null; then
   export CCACHE_CONFIGPATH=$HOME/.config/ccache.conf
   export CCACHE_DIR=$HOME/.cache/ccache
 fi
-which conan &> /dev/null && \
+command -v conan &> /dev/null && \
   export CONAN_USER_HOME=$HOME/.local/share/conan
-which docker &> /dev/null && \
+command -v docker &> /dev/null && \
   export DOCKER_CONFIG=$HOME/.local/share/docker
 export GTK_RC_FILES=$HOME/.config/gtk/gtkrc
 export GTK2_RC_FILES=$HOME/.config/gtk-2.0/gtkrc
-which rustup &> /dev/null && \
+command -v rustup &> /dev/null && \
   export RUSTUP_HOME=$HOME/.local/share/rustup
 export PYLINTHOME=$HOME/.cache/pylint
 # TODO: terminfo
diff --git a/zshrc b/zshrc
index e99bbd0..7f16805 100644
--- a/zshrc
+++ b/zshrc
@@ -68,7 +68,7 @@ autoload -U compinit
 compinit
 
 # Add pip to the old completion engine if present
-if which pip &> /dev/null; then
+if command -v pip &> /dev/null; then
   function _pip_completion {
     local words cword
     read -Ac words
@@ -178,9 +178,9 @@ frequent-directory Projects="$HOME/Projects"
 
 # Aliases
 alias grep='grep --color=always'
-which cmake &> /dev/null && \
+command -v cmake &> /dev/null && \
   alias cninja='cmake -GNinja -DCMAKE_EXPORT_COMPILE_COMMANDS=ON'
-which ssh &> /dev/null && \
+command -v ssh &> /dev/null && \
   alias ssh='TERM=xterm-256color ssh'
 alias weather="curl wttr.in"
 alias cls="clear && printf '\e[3J'"
@@ -188,15 +188,15 @@ alias cls="clear && printf '\e[3J'"
 case `uname` in
   Linux)
     alias ls='ls -F --color=auto'
-    if which cgdb &> /dev/null; then
+    if command -v cgdb &> /dev/null; then
       alias debug='cgdb --args'
-    elif which gdb &> /dev/null; then
+    elif command -v gdb &> /dev/null; then
       alias debug='gdb --args'
     fi
     ;;
   Darwin)
     alias ls='ls -GFh'
-    which lldb &> /dev/null && \
+    command -v lldb &> /dev/null && \
       alias debug='lldb --'
     ;;
 esac