diff --git a/rust/lib/mammoth/src/macros.rs b/rust/lib/mammoth/src/macros.rs
index 8313961..c977a91 100644
--- a/rust/lib/mammoth/src/macros.rs
+++ b/rust/lib/mammoth/src/macros.rs
@@ -50,18 +50,13 @@ macro_rules! debug {
 macro_rules! define_entry {
     () => {
         #[no_mangle]
-        pub extern "C" fn _start(init_port: mammoth::zion::z_cap_t) -> ! {
-            extern "C" {
-                fn main() -> z_err_t;
-            }
-            mammoth::init::parse_init_port(init_port);
-            mammoth::mem::init_heap();
-            unsafe {
-                let err = main();
-                let req = mammoth::zion::ZProcessExitReq { code: err };
-                let _ = mammoth::syscall::syscall(mammoth::zion::kZionProcessExit, &req);
-            }
-            unreachable!()
+        pub extern "C" fn _start(init_port: $crate::zion::z_cap_t) -> ! {
+            $crate::init::parse_init_port(init_port);
+            $crate::mem::init_heap();
+
+            let resp = main();
+
+            $crate::syscall::process_exit(resp);
         }
     };
 }
diff --git a/rust/lib/mammoth/src/syscall.rs b/rust/lib/mammoth/src/syscall.rs
index 3d029bc..0346e7f 100644
--- a/rust/lib/mammoth/src/syscall.rs
+++ b/rust/lib/mammoth/src/syscall.rs
@@ -7,7 +7,7 @@ use core::ffi::c_void;
 use core::panic::PanicInfo;
 
 #[must_use]
-pub fn syscall<T>(id: u64, req: &T) -> Result<(), ZError> {
+fn syscall<T>(id: u64, req: &T) -> Result<(), ZError> {
     unsafe {
         let resp = zion::SysCall1(id, req as *const T as *const c_void);
         if resp != 0 {
@@ -40,6 +40,12 @@ pub fn debug(msg: &str) {
     syscall(zion::kZionDebug, &req).expect("Failed to write");
 }
 
+pub fn process_exit(code: u64) -> ! {
+    let _ = syscall(zion::kZionProcessExit, &zion::ZProcessExitReq { code });
+
+    unreachable!()
+}
+
 pub fn thread_create(proc_cap: z_cap_t) -> Result<z_cap_t, ZError> {
     let mut cap = 0;
     syscall(