diff --git a/decorations/meson.build b/decorations/meson.build
index ca337db..4f40751 100644
--- a/decorations/meson.build
+++ b/decorations/meson.build
@@ -7,7 +7,7 @@ foreach deco : ['background', 'stack', 'underline']
                   dependencies: deco_sdk,
                   name_prefix: 'decoration_',
                   install: true,
-                  install_dir: get_option('libdir') + '/f00bar')
+                  install_dir: join_paths(get_option('libdir'), 'f00bar'))
   else
     lib = static_library(
       'decoration_@0@'.format(deco), '@0@.c'.format(deco), dependencies: deco_sdk)
diff --git a/modules/meson.build b/modules/meson.build
index 523eb3b..0d899c9 100644
--- a/modules/meson.build
+++ b/modules/meson.build
@@ -37,7 +37,7 @@ foreach mod, data : deps
                   dependencies: [module_sdk] + dep,
                   name_prefix: 'module_',
                   install: true,
-                  install_dir: get_option('libdir') + '/f00bar')
+                  install_dir: join_paths(get_option('libdir'), 'f00bar'))
   else
     modules += [declare_dependency(
       sources: ['@0@.c'.format(mod)] + sources,
@@ -56,7 +56,7 @@ if enable_x11
                     dependencies: [module_sdk] + dep,
                     name_prefix: 'module_',
                     install: true,
-                    install_dir: get_option('libdir') + '/f00bar')
+                    install_dir: join_paths(get_option('libdir'), 'f00bar'))
     else
       modules += [declare_dependency(
         sources: ['@0@.c'.format(mod)] + sources,
diff --git a/particles/meson.build b/particles/meson.build
index 766b99e..5ca2804 100644
--- a/particles/meson.build
+++ b/particles/meson.build
@@ -7,7 +7,7 @@ foreach particle : ['empty', 'list', 'map', 'progress-bar', 'ramp', 'string']
                   dependencies: particle_sdk,
                   name_prefix: 'particle_',
                   install: true,
-                  install_dir: get_option('libdir') + '/f00bar')
+                  install_dir: join_paths(get_option('libdir'), 'f00bar'))
   else
     lib = static_library(
       'particle_@0@'.format(particle), '@0@.c'.format(particle),