diff --git a/lib/theme-and-appearance.zsh b/lib/theme-and-appearance.zsh
index 12bcd2849..039a59d2a 100644
--- a/lib/theme-and-appearance.zsh
+++ b/lib/theme-and-appearance.zsh
@@ -6,11 +6,11 @@ export LSCOLORS="Gxfxcxdxbxegedabagacad"
 
 if [[ "$DISABLE_LS_COLORS" != "true" ]]; then
   # Find the option for using colors in ls, depending on the version
-  if [[ "$(uname -s)" == "NetBSD" ]]; then
+  if [[ "$OSTYPE" == netbsd* ]]; then
     # On NetBSD, test if "gls" (GNU ls) is installed (this one supports colors);
     # otherwise, leave ls as is, because NetBSD's ls doesn't support -G
     gls --color -d . &>/dev/null && alias ls='gls --color=tty'
-  elif [[ "$(uname -s)" == "OpenBSD" ]]; then
+  elif [[ "$OSTYPE" == openbsd* ]]; then
     # On OpenBSD, "gls" (ls from GNU coreutils) and "colorls" (ls from base,
     # with color and multibyte support) are available from ports.  "colorls"
     # will be installed on purpose and can't be pulled in by installing
diff --git a/plugins/battery/battery.plugin.zsh b/plugins/battery/battery.plugin.zsh
index 0bb9e77f0..da229cf35 100644
--- a/plugins/battery/battery.plugin.zsh
+++ b/plugins/battery/battery.plugin.zsh
@@ -64,7 +64,7 @@ if [[ "$OSTYPE" = darwin* ]] ; then
     [[ $(ioreg -rc "AppleSmartBattery"| grep '^.*"IsCharging"\ =\ ' | sed -e 's/^.*"IsCharging"\ =\ //') == "Yes" ]]
   }
 
-elif [[ $(uname) == "Linux"  ]] ; then
+elif [[ "$OSTYPE" = linux*  ]] ; then
 
   function battery_is_charging() {
     ! [[ $(acpi 2>/dev/null | grep -c '^Battery.*Discharging') -gt 0 ]]
diff --git a/plugins/gitfast/git-completion.bash b/plugins/gitfast/git-completion.bash
index e3918c87e..8ce6b5c5f 100644
--- a/plugins/gitfast/git-completion.bash
+++ b/plugins/gitfast/git-completion.bash
@@ -2771,6 +2771,6 @@ __git_complete gitk __gitk_main
 # when the user has tab-completed the executable name and consequently
 # included the '.exe' suffix.
 #
-if [ Cygwin = "$(uname -o 2>/dev/null)" ]; then
+if [[ "$OSTYPE" = cygwin* ]]; then
 __git_complete git.exe __git_main
 fi
diff --git a/plugins/sublime/sublime.plugin.zsh b/plugins/sublime/sublime.plugin.zsh
index 75a39eab1..f84b7032a 100644
--- a/plugins/sublime/sublime.plugin.zsh
+++ b/plugins/sublime/sublime.plugin.zsh
@@ -1,4 +1,4 @@
-if [[ $('uname') == 'Linux' ]]; then
+if [[ "$OSTYPE" == linux* ]]; then
     local _sublime_linux_paths > /dev/null 2>&1
     _sublime_linux_paths=(
         "$HOME/bin/sublime_text"
diff --git a/plugins/zsh-navigation-tools/_n-kill b/plugins/zsh-navigation-tools/_n-kill
index 8a4ec9da7..6f5d47971 100644
--- a/plugins/zsh-navigation-tools/_n-kill
+++ b/plugins/zsh-navigation-tools/_n-kill
@@ -10,8 +10,8 @@ integer cygwin=0
 local IFS="
 "
 
-case "$(uname)" in
-    CYGWIN*) list=( `command ps -Wa` ); cygwin=1 ;;
+case "$OSTYPE" in
+    cygwin*) list=( `command ps -Wa` ); cygwin=1 ;;
     *) list=( `command ps -o pid,uid,command -A` ) ;;
 esac
 
diff --git a/plugins/zsh-navigation-tools/n-kill b/plugins/zsh-navigation-tools/n-kill
index 0d10565e4..76050f969 100644
--- a/plugins/zsh-navigation-tools/n-kill
+++ b/plugins/zsh-navigation-tools/n-kill
@@ -42,8 +42,8 @@ NLIST_NONSELECTABLE_ELEMENTS=( 1 )
 
 type ps 2>/dev/null 1>&2 || { echo >&2 "Error: \`ps' not found"; return 1 }
 
-case "$(uname)" in
-    CYGWIN*) list=( `command ps -Wa` )  ;;
+case "$OSTYPE" in
+    cygwin*) list=( `command ps -Wa` )  ;;
     *) list=( `command ps -o pid,uid,command -A` ) ;;
 esac