Index: meson.build
--- meson.build.orig
+++ meson.build
@@ -29,6 +29,8 @@ add_project_arguments(
 cc = meson.get_compiler('c')
 
 is_freebsd = host_machine.system().startswith('freebsd')
+is_openbsd = host_machine.system().startswith('openbsd')
+
 datadir = get_option('datadir')
 sysconfdir = get_option('sysconfdir')
 prefix = get_option('prefix')
@@ -77,7 +79,7 @@ xcb = wlroots_features['xwayland'] ? dependency('xcb')
 drm = dependency('libdrm')
 libudev = wlroots_features['libinput_backend'] ? dependency('libudev') : null_dep
 math = cc.find_library('m')
-rt = cc.find_library('rt')
+rt = cc.find_library('rt', required: not is_openbsd)
 xcb_icccm = wlroots_features['xwayland'] ? dependency('xcb-icccm') : null_dep
 threads = dependency('threads') # for pthread_setschedparam and pthread_atfork
 
