diff --git a/pkgs/development/interpreters/guile/setup-hook-2.0.sh b/pkgs/development/interpreters/guile/setup-hook-2.0.sh
index c7fb4f70fc6a..6bb3910aaff4 100644
--- a/pkgs/development/interpreters/guile/setup-hook-2.0.sh
+++ b/pkgs/development/interpreters/guile/setup-hook-2.0.sh
@@ -1,12 +1,12 @@
 addGuileLibPath () {
     if test -d "$1/share/guile/site/2.0"
     then
-        export GUILE_LOAD_PATH="${GUILE_LOAD_PATH}${GUILE_LOAD_PATH:+:}$1/share/guile/site/2.0"
-        export GUILE_LOAD_COMPILED_PATH="${GUILE_LOAD_COMPILED_PATH}${GUILE_LOAD_COMPILED_PATH:+:}$1/share/guile/site/2.0"
+        export GUILE_LOAD_PATH="${GUILE_LOAD_PATH-}${GUILE_LOAD_PATH:+:}$1/share/guile/site/2.0"
+        export GUILE_LOAD_COMPILED_PATH="${GUILE_LOAD_COMPILED_PATH-}${GUILE_LOAD_COMPILED_PATH:+:}$1/share/guile/site/2.0"
     elif test -d "$1/share/guile/site"
     then
-        export GUILE_LOAD_PATH="${GUILE_LOAD_PATH}${GUILE_LOAD_PATH:+:}$1/share/guile/site"
-        export GUILE_LOAD_COMPILED_PATH="${GUILE_LOAD_COMPILED_PATH}${GUILE_LOAD_COMPILED_PATH:+:}$1/share/guile/site"
+        export GUILE_LOAD_PATH="${GUILE_LOAD_PATH-}${GUILE_LOAD_PATH:+:}$1/share/guile/site"
+        export GUILE_LOAD_COMPILED_PATH="${GUILE_LOAD_COMPILED_PATH-}${GUILE_LOAD_COMPILED_PATH:+:}$1/share/guile/site"
     fi
 }
 
diff --git a/pkgs/development/interpreters/guile/setup-hook-2.2.sh b/pkgs/development/interpreters/guile/setup-hook-2.2.sh
index 73e700bde026..4b3541fcc7f0 100644
--- a/pkgs/development/interpreters/guile/setup-hook-2.2.sh
+++ b/pkgs/development/interpreters/guile/setup-hook-2.2.sh
@@ -1,12 +1,12 @@
 addGuileLibPath () {
     if test -d "$1/share/guile/site/2.2"
     then
-        export GUILE_LOAD_PATH="${GUILE_LOAD_PATH}${GUILE_LOAD_PATH:+:}$1/share/guile/site/2.2"
-        export GUILE_LOAD_COMPILED_PATH="${GUILE_LOAD_COMPILED_PATH}${GUILE_LOAD_COMPILED_PATH:+:}$1/share/guile/site/2.2"
+        export GUILE_LOAD_PATH="${GUILE_LOAD_PATH-}${GUILE_LOAD_PATH:+:}$1/share/guile/site/2.2"
+        export GUILE_LOAD_COMPILED_PATH="${GUILE_LOAD_COMPILED_PATH-}${GUILE_LOAD_COMPILED_PATH:+:}$1/share/guile/site/2.2"
     elif test -d "$1/share/guile/site"
     then
-        export GUILE_LOAD_PATH="${GUILE_LOAD_PATH}${GUILE_LOAD_PATH:+:}$1/share/guile/site"
-        export GUILE_LOAD_COMPILED_PATH="${GUILE_LOAD_COMPILED_PATH}${GUILE_LOAD_COMPILED_PATH:+:}$1/share/guile/site"
+        export GUILE_LOAD_PATH="${GUILE_LOAD_PATH-}${GUILE_LOAD_PATH:+:}$1/share/guile/site"
+        export GUILE_LOAD_COMPILED_PATH="${GUILE_LOAD_COMPILED_PATH-}${GUILE_LOAD_COMPILED_PATH:+:}$1/share/guile/site"
     fi
 }
 
diff --git a/pkgs/development/interpreters/guile/setup-hook.sh b/pkgs/development/interpreters/guile/setup-hook.sh
index bf04fee1e893..d006b50ce8ef 100644
--- a/pkgs/development/interpreters/guile/setup-hook.sh
+++ b/pkgs/development/interpreters/guile/setup-hook.sh
@@ -1,7 +1,7 @@
 addGuileLibPath () {
     if test -d "$1/share/guile/site"
     then
-        export GUILE_LOAD_PATH="${GUILE_LOAD_PATH}${GUILE_LOAD_PATH:+:}$1/share/guile/site"
+        export GUILE_LOAD_PATH="${GUILE_LOAD_PATH-}${GUILE_LOAD_PATH:+:}$1/share/guile/site"
     fi
 }