diff --git a/orbis-kernel/CMakeLists.txt b/orbis-kernel/CMakeLists.txt
index 979f67f31..5a3eeefae 100644
--- a/orbis-kernel/CMakeLists.txt
+++ b/orbis-kernel/CMakeLists.txt
@@ -5,6 +5,7 @@ add_library(obj.orbis-kernel OBJECT
   src/sysvec.cpp
   src/evf.cpp
   src/KernelContext.cpp
+  src/umtx.cpp
   src/sys/sys_acct.cpp
   src/sys/sys_audit.cpp
   src/sys/sys_capability.cpp
diff --git a/orbis-kernel/include/orbis/umtx.hpp b/orbis-kernel/include/orbis/umtx.hpp
new file mode 100644
index 000000000..5863cc0d5
--- /dev/null
+++ b/orbis-kernel/include/orbis/umtx.hpp
@@ -0,0 +1,31 @@
+#pragma once
+
+#include "error/ErrorCode.hpp"
+#include "orbis-config.hpp"
+
+namespace orbis {
+struct Thread;
+ErrorCode umtx_lock_umtx(Thread *thread, ptr<void> obj, std::int64_t val, ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_unlock_umtx(Thread *thread, ptr<void> obj, std::int64_t val, ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_wait(Thread *thread, ptr<void> obj, std::int64_t val, ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_wake(Thread *thread, ptr<void> obj, std::int64_t val, ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_trylock_umutex(Thread *thread, ptr<void> obj, std::int64_t val, ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_lock_umutex(Thread *thread, ptr<void> obj, std::int64_t val, ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_unlock_umutex(Thread *thread, ptr<void> obj, std::int64_t val, ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_set_ceiling(Thread *thread, ptr<void> obj, std::int64_t val, ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_cv_wait(Thread *thread, ptr<void> obj, std::int64_t val, ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_cv_signal(Thread *thread, ptr<void> obj, std::int64_t val, ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_cv_broadcast(Thread *thread, ptr<void> obj, std::int64_t val, ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_wait_uint(Thread *thread, ptr<void> obj, std::int64_t val, ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_rw_rdlock(Thread *thread, ptr<void> obj, std::int64_t val, ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_rw_wrlock(Thread *thread, ptr<void> obj, std::int64_t val, ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_rw_unlock(Thread *thread, ptr<void> obj, std::int64_t val, ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_wait_uint_private(Thread *thread, ptr<void> obj, std::int64_t val, ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_wake_private(Thread *thread, ptr<void> obj, std::int64_t val, ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_wait_umutex(Thread *thread, ptr<void> obj, std::int64_t val, ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_wake_umutex(Thread *thread, ptr<void> obj, std::int64_t val, ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_sem_wait(Thread *thread, ptr<void> obj, std::int64_t val, ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_sem_wake(Thread *thread, ptr<void> obj, std::int64_t val, ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_nwake_private(Thread *thread, ptr<void> obj, std::int64_t val, ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_wake2_umutex(Thread *thread, ptr<void> obj, std::int64_t val, ptr<void> uaddr1, ptr<void> uaddr2);
+}
\ No newline at end of file
diff --git a/orbis-kernel/src/sys/sys_umtx.cpp b/orbis-kernel/src/sys/sys_umtx.cpp
index f9290da73..7feaa5020 100644
--- a/orbis-kernel/src/sys/sys_umtx.cpp
+++ b/orbis-kernel/src/sys/sys_umtx.cpp
@@ -1,15 +1,64 @@
 #include "sys/sysproto.hpp"
+#include "umtx.hpp"
 
 orbis::SysResult orbis::sys__umtx_lock(Thread *thread, ptr<struct umtx> umtx) {
-  return ErrorCode::NOSYS;
+  return umtx_lock_umtx(thread, umtx, 0, 0, 0);
 }
 orbis::SysResult orbis::sys__umtx_unlock(Thread *thread,
                                          ptr<struct umtx> umtx) {
-  return ErrorCode::NOSYS;
+  return umtx_lock_umtx(thread, umtx, thread->tid, 0, 0);
 }
 orbis::SysResult orbis::sys__umtx_op(Thread *thread, ptr<void> obj, sint op,
                                      ulong val, ptr<void> uaddr1,
                                      ptr<void> uaddr2) {
-  std::printf("TODO: sys__umtx_op\n");
-  return {};
+  switch (op) {
+  case 0:
+    return umtx_lock_umtx(thread, obj, val, uaddr1, uaddr2);
+  case 1:
+    return umtx_unlock_umtx(thread, obj, val, uaddr1, uaddr2);
+  case 2:
+    return umtx_wait(thread, obj, val, uaddr1, uaddr2);
+  case 3:
+    return umtx_wake(thread, obj, val, uaddr1, uaddr2);
+  case 4:
+    return umtx_trylock_umutex(thread, obj, val, uaddr1, uaddr2);
+  case 5:
+    return umtx_lock_umutex(thread, obj, val, uaddr1, uaddr2);
+  case 6:
+    return umtx_unlock_umutex(thread, obj, val, uaddr1, uaddr2);
+  case 7:
+    return umtx_set_ceiling(thread, obj, val, uaddr1, uaddr2);
+  case 8:
+    return umtx_cv_wait(thread, obj, val, uaddr1, uaddr2);
+  case 9:
+    return umtx_cv_signal(thread, obj, val, uaddr1, uaddr2);
+  case 10:
+    return umtx_cv_broadcast(thread, obj, val, uaddr1, uaddr2);
+  case 11:
+    return umtx_wait_uint(thread, obj, val, uaddr1, uaddr2);
+  case 12:
+    return umtx_rw_rdlock(thread, obj, val, uaddr1, uaddr2);
+  case 13:
+    return umtx_rw_wrlock(thread, obj, val, uaddr1, uaddr2);
+  case 14:
+    return umtx_rw_unlock(thread, obj, val, uaddr1, uaddr2);
+  case 15:
+    return umtx_wait_uint_private(thread, obj, val, uaddr1, uaddr2);
+  case 16:
+    return umtx_wake_private(thread, obj, val, uaddr1, uaddr2);
+  case 17:
+    return umtx_wait_umutex(thread, obj, val, uaddr1, uaddr2);
+  case 18:
+    return umtx_wake_umutex(thread, obj, val, uaddr1, uaddr2);
+  case 19:
+    return umtx_sem_wait(thread, obj, val, uaddr1, uaddr2);
+  case 20:
+    return umtx_sem_wake(thread, obj, val, uaddr1, uaddr2);
+  case 21:
+    return umtx_nwake_private(thread, obj, val, uaddr1, uaddr2);
+  case 22:
+    return umtx_wake2_umutex(thread, obj, val, uaddr1, uaddr2);
+  }
+
+  return ErrorCode::INVAL;
 }
diff --git a/orbis-kernel/src/umtx.cpp b/orbis-kernel/src/umtx.cpp
new file mode 100644
index 000000000..32d608d34
--- /dev/null
+++ b/orbis-kernel/src/umtx.cpp
@@ -0,0 +1,140 @@
+#include "umtx.hpp"
+
+orbis::ErrorCode orbis::umtx_lock_umtx(Thread *thread, ptr<void> obj,
+                                       std::int64_t val, ptr<void> uaddr1,
+                                       ptr<void> uaddr2) {
+  return ErrorCode::NOSYS;
+}
+
+orbis::ErrorCode orbis::umtx_unlock_umtx(Thread *thread, ptr<void> obj,
+                                         std::int64_t val, ptr<void> uaddr1,
+                                         ptr<void> uaddr2) {
+  return ErrorCode::NOSYS;
+}
+
+orbis::ErrorCode orbis::umtx_wait(Thread *thread, ptr<void> obj,
+                                  std::int64_t val, ptr<void> uaddr1,
+                                  ptr<void> uaddr2) {
+  return ErrorCode::NOSYS;
+}
+
+orbis::ErrorCode orbis::umtx_wake(Thread *thread, ptr<void> obj,
+                                  std::int64_t val, ptr<void> uaddr1,
+                                  ptr<void> uaddr2) {
+  return ErrorCode::NOSYS;
+}
+
+orbis::ErrorCode orbis::umtx_trylock_umutex(Thread *thread, ptr<void> obj,
+                                            std::int64_t val, ptr<void> uaddr1,
+                                            ptr<void> uaddr2) {
+  return ErrorCode::NOSYS;
+}
+
+orbis::ErrorCode orbis::umtx_lock_umutex(Thread *thread, ptr<void> obj,
+                                         std::int64_t val, ptr<void> uaddr1,
+                                         ptr<void> uaddr2) {
+  return ErrorCode::NOSYS;
+}
+
+orbis::ErrorCode orbis::umtx_unlock_umutex(Thread *thread, ptr<void> obj,
+                                           std::int64_t val, ptr<void> uaddr1,
+                                           ptr<void> uaddr2) {
+  return ErrorCode::NOSYS;
+}
+
+orbis::ErrorCode orbis::umtx_set_ceiling(Thread *thread, ptr<void> obj,
+                                         std::int64_t val, ptr<void> uaddr1,
+                                         ptr<void> uaddr2) {
+  return ErrorCode::NOSYS;
+}
+
+orbis::ErrorCode orbis::umtx_cv_wait(Thread *thread, ptr<void> obj,
+                                     std::int64_t val, ptr<void> uaddr1,
+                                     ptr<void> uaddr2) {
+  return ErrorCode::NOSYS;
+}
+
+orbis::ErrorCode orbis::umtx_cv_signal(Thread *thread, ptr<void> obj,
+                                       std::int64_t val, ptr<void> uaddr1,
+                                       ptr<void> uaddr2) {
+  return ErrorCode::NOSYS;
+}
+
+orbis::ErrorCode orbis::umtx_cv_broadcast(Thread *thread, ptr<void> obj,
+                                          std::int64_t val, ptr<void> uaddr1,
+                                          ptr<void> uaddr2) {
+  return ErrorCode::NOSYS;
+}
+
+orbis::ErrorCode orbis::umtx_wait_uint(Thread *thread, ptr<void> obj,
+                                       std::int64_t val, ptr<void> uaddr1,
+                                       ptr<void> uaddr2) {
+  return ErrorCode::NOSYS;
+}
+
+orbis::ErrorCode orbis::umtx_rw_rdlock(Thread *thread, ptr<void> obj,
+                                       std::int64_t val, ptr<void> uaddr1,
+                                       ptr<void> uaddr2) {
+  return ErrorCode::NOSYS;
+}
+
+orbis::ErrorCode orbis::umtx_rw_wrlock(Thread *thread, ptr<void> obj,
+                                       std::int64_t val, ptr<void> uaddr1,
+                                       ptr<void> uaddr2) {
+  return ErrorCode::NOSYS;
+}
+
+orbis::ErrorCode orbis::umtx_rw_unlock(Thread *thread, ptr<void> obj,
+                                       std::int64_t val, ptr<void> uaddr1,
+                                       ptr<void> uaddr2) {
+  return ErrorCode::NOSYS;
+}
+
+orbis::ErrorCode orbis::umtx_wait_uint_private(Thread *thread, ptr<void> obj,
+                                               std::int64_t val,
+                                               ptr<void> uaddr1,
+                                               ptr<void> uaddr2) {
+  return ErrorCode::NOSYS;
+}
+
+orbis::ErrorCode orbis::umtx_wake_private(Thread *thread, ptr<void> obj,
+                                          std::int64_t val, ptr<void> uaddr1,
+                                          ptr<void> uaddr2) {
+  return ErrorCode::NOSYS;
+}
+
+orbis::ErrorCode orbis::umtx_wait_umutex(Thread *thread, ptr<void> obj,
+                                         std::int64_t val, ptr<void> uaddr1,
+                                         ptr<void> uaddr2) {
+  return ErrorCode::NOSYS;
+}
+
+orbis::ErrorCode orbis::umtx_wake_umutex(Thread *thread, ptr<void> obj,
+                                         std::int64_t val, ptr<void> uaddr1,
+                                         ptr<void> uaddr2) {
+  return ErrorCode::NOSYS;
+}
+
+orbis::ErrorCode orbis::umtx_sem_wait(Thread *thread, ptr<void> obj,
+                                      std::int64_t val, ptr<void> uaddr1,
+                                      ptr<void> uaddr2) {
+  return ErrorCode::NOSYS;
+}
+
+orbis::ErrorCode orbis::umtx_sem_wake(Thread *thread, ptr<void> obj,
+                                      std::int64_t val, ptr<void> uaddr1,
+                                      ptr<void> uaddr2) {
+  return ErrorCode::NOSYS;
+}
+
+orbis::ErrorCode orbis::umtx_nwake_private(Thread *thread, ptr<void> obj,
+                                           std::int64_t val, ptr<void> uaddr1,
+                                           ptr<void> uaddr2) {
+  return ErrorCode::NOSYS;
+}
+
+orbis::ErrorCode orbis::umtx_wake2_umutex(Thread *thread, ptr<void> obj,
+                                          std::int64_t val, ptr<void> uaddr1,
+                                          ptr<void> uaddr2) {
+  return ErrorCode::NOSYS;
+}