from another hand here is quite small approach which seems to wrok:

~ $ ps auxww | grep codex | grep app-server
~ $ codex app-server daemon start          
{"status":"started","backend":"pid","pid":49277,"managedCodexPath":"/usr/local/bin/codex","managedCodexVersion":"0.162.1","socketPath":"/home/catap/.codex/app-server-control/app-server-control.sock","cliVersion":"0.162.1","appServerVersion":"0.162.1"}
~ $ ps auxww | grep codex | grep app-server
catap    49277  1.6  0.1  945864  113476 ??  S      12:15AM    0:00.70 /usr/local/bin/codex app-server --listen unix:// --analytics-default-enabled --managed-daemon
~ $ codex app-server daemon version         
{"status":"running","backend":"pid","managedCodexPath":"/usr/local/bin/codex","managedCodexVersion":"0.162.1","socketPath":"/home/catap/.codex/app-server-control/app-server-control.sock","cliVersion":"0.162.1","appServerVersion":"0.162.1"}
~ $ codex app-server daemon stop    
{"status":"stopped","backend":"pid","managedCodexPath":"/usr/local/bin/codex","managedCodexVersion":"0.162.1","socketPath":"/home/catap/.codex/app-server-control/app-server-control.sock","cliVersion":"0.162.1"}
~ $ ps auxww | grep codex | grep app-server 
~ $ 

If you willing to test here prebuild amd64 packages:
https://kirill.korins.ky/pub/packages/codex-0.162.1p0.tgz

Index: Makefile
===================================================================
RCS file: /home/cvs/ports/devel/codex/Makefile,v
diff -u -p -r1.59 Makefile
--- Makefile	10 Oct 2026 12:50:48 -0000	1.59
+++ Makefile	14 Oct 2026 21:12:22 -0000
@@ -13,6 +13,7 @@ DPB_PROPERTIES =	parallel
 USE_WXNEEDED =		Yes
 
 V =			0.162.1
+REVISION =		0
 GH_ACCOUNT =		openai
 GH_PROJECT =		codex
 GH_TAGNAME =		rust-v${V}
Index: patches/patch-codex-rs_app-server-daemon_src_lib_rs
===================================================================
RCS file: patches/patch-codex-rs_app-server-daemon_src_lib_rs
diff -N patches/patch-codex-rs_app-server-daemon_src_lib_rs
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ patches/patch-codex-rs_app-server-daemon_src_lib_rs	14 Oct 2026 21:08:57 -0000
@@ -0,0 +1,25 @@
+Index: codex-rs/app-server-daemon/src/lib.rs
+--- codex-rs/app-server-daemon/src/lib.rs.orig
++++ codex-rs/app-server-daemon/src/lib.rs
+@@ -328,7 +328,7 @@ impl Daemon {
+             .as_path()
+             .to_path_buf();
+         let state_dir = codex_home.as_path().join(STATE_DIR_NAME);
+-        let managed_codex_bin = managed_codex_bin(codex_home.as_path());
++        let managed_codex_bin = std::env::current_exe()?;
+         // Old CLIs must not mistake a daemon-owned installation for their backend.
+         let (pid_file, update_pid_file) =
+             if managed_codex_bin.starts_with(codex_home.as_path().join("packages/standalone")) {
+@@ -941,6 +941,12 @@ impl Daemon {
+         ))
+     }
+ 
++    #[cfg(target_os = "openbsd")]
++    fn current_managed_codex_bin(&self) -> Result<PathBuf> {
++        Ok(self.managed_codex_bin.clone())
++    }
++
++    #[cfg(not(target_os = "openbsd"))]
+     fn current_managed_codex_bin(&self) -> Result<PathBuf> {
+         // An installer can move a legacy binary into bin/ while this updater runs.
+         let home = self
Index: patches/patch-codex-rs_app-server-daemon_src_prepare_install_rs
===================================================================
RCS file: patches/patch-codex-rs_app-server-daemon_src_prepare_install_rs
diff -N patches/patch-codex-rs_app-server-daemon_src_prepare_install_rs
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ patches/patch-codex-rs_app-server-daemon_src_prepare_install_rs	14 Oct 2026 21:08:53 -0000
@@ -0,0 +1,16 @@
+Index: codex-rs/app-server-daemon/src/prepare_install.rs
+--- codex-rs/app-server-daemon/src/prepare_install.rs.orig
++++ codex-rs/app-server-daemon/src/prepare_install.rs
+@@ -24,6 +24,12 @@ pub struct InstallRequest {
+     pub restart_required: bool,
+ }
+ 
++#[cfg(target_os = "openbsd")]
++pub(super) async fn prepare(daemon: &Daemon, _settings: &DaemonSettings) -> Result<()> {
++    daemon.ensure_managed_codex_bin()
++}
++
++#[cfg(not(target_os = "openbsd"))]
+ /// Prepare a missing package while the caller holds the daemon operation lock.
+ pub(super) async fn prepare(daemon: &Daemon, settings: &DaemonSettings) -> Result<()> {
+     let source = InstallContext::current().package_layout.as_ref();


-- 
wbr, Kirill