--- meson.build.orig	2026-09-22 11:50:27 UTC
+++ meson.build
@@ -22,7 +22,17 @@ swscale_dep = dependency('libswscale')
 avcodec_dep = dependency('libavcodec')
 avutil_dep = dependency('libavutil')
 swscale_dep = dependency('libswscale')
-libsystemd_dep = dependency('libsystemd')
+libsystemd_dep = dependency('libsystemd', required : false)
+if libsystemd_dep.found()
+  add_project_arguments('-DHAVE_LIBSYSTEMD', language : 'c')
+else
+  # Systems without systemd (e.g. FreeBSD) get sd-bus from basu; the
+  # sd-login session lookup falls back to $XDG_SESSION_ID.
+  libsystemd_dep = dependency('basu')
+endif
+if cc.has_function('sd_bus_close_unref', dependencies : libsystemd_dep)
+  add_project_arguments('-DHAVE_SD_BUS_CLOSE_UNREF', language : 'c')
+endif
 threads_dep = dependency('threads')
 
 wayland_scanner = find_program('wayland-scanner')