--- meson.build.orig	2026-09-12 12:52:03 UTC
+++ meson.build
@@ -12,12 +12,16 @@ endif
     endif
 endif
 
+osname = build_machine.system()
+
 prefix = get_option('prefix')
 sysconfdir = get_option('sysconfdir')
 
 # If sysconfdir starts with prefix, strip the prefix.
-if sysconfdir.startswith(prefix) and not is_nixos
-  sysconfdir = sysconfdir.substring(prefix.length())
+if sysconfdir.startswith(prefix) and not is_nixos and osname != 'freebsd'
+  # this fails with: Unknown method "length" in object <[OptionStringHolder] holds [OptionString]
+  # sysconfdir = sysconfdir.substring(prefix.length())
+  sysconfdir = sysconfdir.replace(prefix, '')
   # Ensure sysconfdir is an absolute path.
   if not sysconfdir.startswith('/')
     sysconfdir = '/' + sysconfdir
@@ -72,9 +76,8 @@ c_args = [
   '-Wno-unused-function',
   '-Wno-unused-result',
   '-DWLR_USE_UNSTABLE',
-  '-D_POSIX_C_SOURCE=200809L',
   '-DVERSION="@0@"'.format(version_with_hash),
-  '-DSYSCONFDIR="@0@"'.format('/etc'),
+  '-DSYSCONFDIR="@0@"'.format(sysconfdir),
 ]
 
 # add debug args only when debug option is enabled