diff --git a/src/kernel/emulation/linux/CMakeLists.txt b/src/kernel/emulation/linux/CMakeLists.txt
index 471388283..a354277e8 100644
--- a/src/kernel/emulation/linux/CMakeLists.txt
+++ b/src/kernel/emulation/linux/CMakeLists.txt
@@ -131,6 +131,7 @@ set(emulation_sources
 	signal/sigprocmask.c
 	signal/sig_restorer.S
 	signal/sigsuspend.c
+	misc/ptrace.c
 	misc/getentropy.c
 	misc/syscall.c
 	misc/shared_region_check_np.c
diff --git a/src/kernel/emulation/linux/misc/ptrace.c b/src/kernel/emulation/linux/misc/ptrace.c
new file mode 100644
index 000000000..0e34923c4
--- /dev/null
+++ b/src/kernel/emulation/linux/misc/ptrace.c
@@ -0,0 +1,88 @@
+#include "ptrace.h"
+#include "../base.h"
+#include "../simple.h"
+#include "../errno.h"
+#include <sys/errno.h>
+#include <stddef.h>
+#include <linux-syscalls/linux.h>
+#include <sys/signal.h>
+#include "../signal/kill.h"
+#include "../signal/duct_signals.h"
+
+#define LINUX_PTRACE_TRACEME	0
+#define LINUX_PTRACE_ATTACH	16
+#define LINUX_PTRACE_DETACH	17
+#define LINUX_PTRACE_CONT	7
+
+long sys_ptrace(int request, int pid, void* addr, int data)
+{
+	const char* cmd = NULL;
+
+	switch (request)
+	{
+		case PT_PTRACE_ME:
+		{
+			int ret = LINUX_SYSCALL(__NR_ptrace, LINUX_PTRACE_TRACEME, pid, addr, data);
+			
+			if (ret < 0)
+				ret = errno_linux_to_bsd(ret);
+			
+			return ret;
+			//cmd = "PT_PTRACE_ME"; break;
+		}
+		case PT_KILL:
+			return sys_kill(pid, SIGKILL, 1);
+			// cmd = "PT_KILL"; break;
+		case PT_ATTACH: // PT_ATTACH
+		case PT_ATTACHEXC: // PT_ATTACHEXC
+		{
+		//do_attach:
+			int ret = LINUX_SYSCALL(__NR_ptrace, LINUX_PTRACE_ATTACH, pid, addr, data);
+			
+			if (ret < 0)
+				ret = errno_linux_to_bsd(ret);
+			
+			return ret;
+			// cmd = "PT_ATTACH"; break;
+		}
+		case PT_DETACH:
+		{
+			int ret = LINUX_SYSCALL(__NR_ptrace, LINUX_PTRACE_DETACH, pid, addr, data);
+			
+			if (ret < 0)
+				ret = errno_linux_to_bsd(ret);
+			
+			return ret;
+			// cmd = "PT_DETACH"; break;
+		}
+		case PT_SIGEXC:
+			cmd = "PT_SIGEXC"; break;
+		case PT_CONTINUE:
+		// case PT_THUPDATE:
+		{
+			int signal = 0;
+			if (data != -1)
+				signal = signum_bsd_to_linux(data);
+			int ret = LINUX_SYSCALL(__NR_ptrace, LINUX_PTRACE_CONT, pid, NULL, signal);
+			
+			if (ret < 0)
+				ret = errno_linux_to_bsd(ret);
+			
+			return ret;
+			// cmd = "PT_THUPDATE"; break;
+		}
+		//case 14:
+		//{
+		//	goto do_attach;
+			// cmd = "PT_ATTACHEXC"; break;
+		//}
+	}
+
+	if (cmd != NULL)
+		__simple_printf("ptrace() req=%s\n", cmd);
+	else
+		__simple_printf("ptrace() req=%d\n", request);
+
+	return -ENOSYS;
+}
+
diff --git a/src/kernel/emulation/linux/misc/ptrace.h b/src/kernel/emulation/linux/misc/ptrace.h
new file mode 100644
index 000000000..85205de07
--- /dev/null
+++ b/src/kernel/emulation/linux/misc/ptrace.h
@@ -0,0 +1,16 @@
+#ifndef LINUX_PTRACE_H
+#define LINUX_PTRACE_H
+
+#define PT_PTRACE_ME 0
+#define PT_CONTINUE 7
+#define PT_KILL 8
+#define PT_ATTACH 10
+#define PT_ATTACHEXC 14
+#define PT_DETACH 11
+#define PT_SIGEXC 12
+#define PT_THUPDATE 13
+
+long sys_ptrace(int request, int pid, void* addr, int data);
+
+#endif
+
diff --git a/src/kernel/emulation/linux/process/wait4.c b/src/kernel/emulation/linux/process/wait4.c
index 4fa09bdbc..89ba6d06d 100644
--- a/src/kernel/emulation/linux/process/wait4.c
+++ b/src/kernel/emulation/linux/process/wait4.c
@@ -2,19 +2,28 @@
 #include "../base.h"
 #include "../errno.h"
 #include "../signal/duct_signals.h"
+#include "../misc/ptrace.h"
+#include <sys/signal.h>
+#include <stddef.h>
 #include <linux-syscalls/linux.h>
 
 long sys_wait4(int pid, int* status, int options, void* rusage)
 {
 	int ret, linux_options;
+	int mystatus;
+
+	// We always need status even if the caller doesn't
+	if (status == NULL)
+		status = &mystatus;
 
 	linux_options = waitopts_bsd_to_linux(options);
 
+restart:
 	ret = LINUX_SYSCALL(__NR_wait4, pid, status, linux_options, rusage);
 	if (ret < 0)
 		return errno_linux_to_bsd(ret);
 
-	if ((*status & 0x7f) != 0x7f)
+	if ((*status & 0x7f) != 0x7f) // process terminated
 	{
 		int signum;
 
@@ -24,6 +33,29 @@ long sys_wait4(int pid, int* status, int options, void* rusage)
 	}
 	else if (*status == 0xffff) // Linux: __W_CONTINUED
 		*status = 0x7f | (0x13 << 8);
+	else if ((*status & 0x7f) == 0x7f) // process stopped
+	{
+		int signal = *status >> 8;
+		signal = signum_linux_to_bsd(signal);
+		*status = (*status & 0x7f) | (signal << 8);
+
+		switch (signal)
+		{
+			case SIGCONT:
+			case SIGSTOP:
+			case SIGTSTP:
+			case SIGTTIN:
+			case SIGTTOU:
+				// It is standard behavior that these signals stop (resume) the process
+				break;
+			default:
+				// We are probably ptracing the target process.
+				// Allow the execution to continue so that the ptraced process can translate
+				// the signal into a Mach message.
+				sys_ptrace(PT_CONTINUE, ret, NULL, signal);
+				goto restart;
+		}
+	}
 
 	return ret;
 }
diff --git a/src/kernel/emulation/linux/syscalls.c b/src/kernel/emulation/linux/syscalls.c
index 9fcdf29bf..c782f9aab 100644
--- a/src/kernel/emulation/linux/syscalls.c
+++ b/src/kernel/emulation/linux/syscalls.c
@@ -98,6 +98,7 @@
 #include "process/getpriority.h"
 #include "process/setpriority.h"
 #include "misc/getentropy.h"
+#include "misc/ptrace.h"
 #include "misc/getlogin.h"
 #include "misc/setlogin.h"
 #include "misc/reboot.h"
@@ -209,6 +210,7 @@ void* __bsd_syscall_table[600] = {
 	[23] = sys_setuid,
 	[24] = sys_getuid,
 	[25] = sys_geteuid,
+	[26] = sys_ptrace,
 	[27] = sys_recvmsg,
 	[28] = sys_sendmsg,
 	[29] = sys_recvfrom,