diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7852235..06c9b7b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -190,6 +190,8 @@ set(SOURCES
   src/stdlib/strtoll.c
   src/stdlib/strtoul.c
   src/stdlib/strtoull.c
+  # unistd
+  src/unistd/_exit.c
   # string
   src/string/memchr.c
   src/string/memcmp.c
diff --git a/include/unistd.h b/include/unistd.h
index faf2394..886fa4f 100644
--- a/include/unistd.h
+++ b/include/unistd.h
@@ -45,6 +45,10 @@ extern char *getcwd(char *__buf, size_t __size);
 
 extern int chdir(char const *__path);
 
+/* Exit immediately, bypassing exit handlers or signal handlers. */
+__attribute__((noreturn))
+extern void _exit(int __status);
+
 
 /* Kernel-style functions supported only by Vhex. */
 
diff --git a/src/unistd/_exit.c b/src/unistd/_exit.c
new file mode 100644
index 0000000..c7199fa
--- /dev/null
+++ b/src/unistd/_exit.c
@@ -0,0 +1,4 @@
+#include <unistd.h>
+
+/* Exit immediately, bypassing exit handlers or signal handlers. */
+void _exit(int status) __attribute__((alias("_Exit")));