diff --git a/src/bin/debug/ltrace/arch/x86_64/Jamfile b/src/bin/debug/ltrace/arch/x86_64/Jamfile
index f2844ebb89..3d30ffd8dc 100644
--- a/src/bin/debug/ltrace/arch/x86_64/Jamfile
+++ b/src/bin/debug/ltrace/arch/x86_64/Jamfile
@@ -1,3 +1,8 @@
 SubDir HAIKU_TOP src bin debug ltrace arch x86_64 ;
 
-# TODO: Implement!
+UsePrivateSystemHeaders ;
+
+StaticLibrary arch_ltrace_stub.a
+	:
+	arch_ltrace_stub.S
+;
diff --git a/src/bin/debug/ltrace/arch/x86_64/arch_ltrace_stub.S b/src/bin/debug/ltrace/arch/x86_64/arch_ltrace_stub.S
new file mode 100644
index 0000000000..056b9f4c14
--- /dev/null
+++ b/src/bin/debug/ltrace/arch/x86_64/arch_ltrace_stub.S
@@ -0,0 +1,72 @@
+/*
+ * Copyright 2019, Jérôme Duval, jerome.duval@gmail.com.
+ * Copyright 2008, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+
+#include <asm_defs.h>
+
+
+call_stub:
+	// push arguments on the stack
+	push	%r9
+	push	%r8
+	push	%rcx
+	push	%rdx
+	push	%rsi
+	push	%rdi
+	// pointer to ourself
+	lea		call_stub(%rip), %rdi
+	// pointer to first argument
+	mov		%rsp, %rsi
+
+	// call the wrapper function
+	movq	(call_stub_callback_address - call_stub)(%rdi), %rax
+	call	*%rax
+				// returns a pointer to the actual function
+	// restore arguments before calling
+	pop		%rdi
+	pop		%rsi
+	pop		%rdx
+	pop		%rcx
+	pop		%r8
+	pop		%r9
+	jmp		*%rax
+
+.align 8
+call_stub_callback_address:
+	.long	0
+call_stub_end:
+
+
+// size_t arch_call_stub_size();
+FUNCTION(arch_call_stub_size):
+	movq	$(call_stub_end - call_stub), %rax
+	ret
+FUNCTION_END(arch_call_stub_size)
+
+
+// void arch_init_call_stub(void* stub,
+//		void* (*callback)(const void* stub, const void* args),
+//		void* function);
+FUNCTION(arch_init_call_stub):
+	push	%rbp
+	movq	%rsp, %rbp
+
+	push	%rsi
+	push	%rdi
+
+	// copy the stub
+	movq	$(call_stub_end - call_stub), %rdx
+	lea		call_stub(%rip), %rsi
+	call	memcpy@plt
+
+	// set the callback address in the stub
+	pop		%rdi
+	pop		%rsi
+	movq	%rsi, (call_stub_callback_address - call_stub)(%rdi)
+
+	movq	%rbp, %rsp
+	pop		%rbp
+	ret
+FUNCTION_END(arch_init_call_stub)
diff --git a/src/bin/debug/ltrace/ltrace_stub.cpp b/src/bin/debug/ltrace/ltrace_stub.cpp
index f34949092b..28958da4ca 100644
--- a/src/bin/debug/ltrace/ltrace_stub.cpp
+++ b/src/bin/debug/ltrace/ltrace_stub.cpp
@@ -33,6 +33,7 @@ struct PatchEntry {
 
 	static PatchEntry* Create(const char* name, void* function)
 	{
+		// TODO memory should be executable, use mmap with PROT_EXEC
 		void* memory = malloc(_ALIGN(sizeof(PatchEntry))
 			+ arch_call_stub_size());
 		if (memory == NULL)
@@ -125,7 +126,7 @@ TRACE_PRINTF("function_call_callback(): CALLED FOR UNKNOWN FUNCTION!\n");
 	size_t bufferSize = sizeof(buffer);
 	size_t written = 0;
 
-	const uint32* args = (const uint32*)_args;
+	const ulong* args = (const ulong*)_args;
 	written += snprintf(buffer, bufferSize, "ltrace: %s(",
 		entry->functionName);
 	for (int32 i = 0; i < 5; i++) {
@@ -143,7 +144,7 @@ static void
 symbol_patcher(void* cookie, image_t* rootImage, image_t* image,
 	const char* name, image_t** foundInImage, void** symbol, int32* type)
 {
-	TRACE_PRINTF("symbol_patcher(%p, %p, %p, \"%s\", %p, %p, %ld)\n",
+	TRACE_PRINTF("symbol_patcher(%p, %p, %p, \"%s\", %p, %p, %" B_PRId32 ")\n",
 		cookie, rootImage, image, name, *foundInImage, *symbol, *type);
 
 	// patch functions only
@@ -188,8 +189,8 @@ ltrace_stub_init(rld_export* standardInterface,
 static void
 ltrace_stub_image_loaded(image_t* image)
 {
-	TRACE_PRINTF("ltrace_stub_image_loaded(%p): \"%s\" (%ld)\n", image, image->path,
-		image->id);
+	TRACE_PRINTF("ltrace_stub_image_loaded(%p): \"%s\" (%" B_PRId32 ")\n",
+		image, image->path, image->id);
 
 	if (sRuntimeLoaderAddOnInterface->register_undefined_symbol_patcher(image,
 			symbol_patcher, (void*)(addr_t)0xc0011eaf) != B_OK) {
@@ -201,32 +202,32 @@ ltrace_stub_image_loaded(image_t* image)
 static void
 ltrace_stub_image_relocated(image_t* image)
 {
-	TRACE_PRINTF("ltrace_stub_image_relocated(%p): \"%s\" (%ld)\n", image,
-		image->path, image->id);
+	TRACE_PRINTF("ltrace_stub_image_relocated(%p): \"%s\" (%" B_PRId32 ")\n",
+		image, image->path, image->id);
 }
 
 
 static void
 ltrace_stub_image_initialized(image_t* image)
 {
-	TRACE_PRINTF("ltrace_stub_image_initialized(%p): \"%s\" (%ld)\n", image,
-		image->path, image->id);
+	TRACE_PRINTF("ltrace_stub_image_initialized(%p): \"%s\" (%" B_PRId32 ")\n",
+		image, image->path, image->id);
 }
 
 
 static void
 ltrace_stub_image_uninitializing(image_t* image)
 {
-	TRACE_PRINTF("ltrace_stub_image_uninitializing(%p): \"%s\" (%ld)\n", image,
-		image->path, image->id);
+	TRACE_PRINTF("ltrace_stub_image_uninitializing(%p): \"%s\" (%" B_PRId32
+		")\n",image, image->path, image->id);
 }
 
 
 static void
 ltrace_stub_image_unloading(image_t* image)
 {
-	TRACE_PRINTF("ltrace_stub_image_unloading(%p): \"%s\" (%ld)\n", image,
-		image->path, image->id);
+	TRACE_PRINTF("ltrace_stub_image_unloading(%p): \"%s\" (%" B_PRId32 ")\n",
+		image, image->path, image->id);
 }