diff --git a/src/modules/main/console.cpp b/src/modules/main/console.cpp
index a71c6b2..540fae4 100644
--- a/src/modules/main/console.cpp
+++ b/src/modules/main/console.cpp
@@ -2,6 +2,8 @@
 
 const char digits[] = "0123456789abcdef";
 
+console *console::default_console = nullptr;
+
 console::console(const font &f, const screen &s, void *scratch, size_t len) :
 	m_font(f),
 	m_screen(s),
@@ -73,6 +75,9 @@ console::console(const font &f, const screen &s, void *scratch, size_t len) :
 	}
 
 	repaint();
+
+	if (default_console == nullptr)
+		default_console = this;
 }
 
 char *
diff --git a/src/modules/main/console.h b/src/modules/main/console.h
index 11fb01a..3f748d8 100644
--- a/src/modules/main/console.h
+++ b/src/modules/main/console.h
@@ -22,7 +22,10 @@ public:
 	template <typename T>
 	void put_hex(T x);
 
-	void put_dec(uint32_t x);
+	template <typename T>
+	void put_dec(T x);
+
+	static console * get() { return default_console; }
 
 private:
 	char * line_pointer(unsigned line);
@@ -42,6 +45,8 @@ private:
 	char *m_data;
 	uint16_t *m_attrs;
 	screen::pixel_t *m_palette;
+
+	static console *default_console;
 };
 
 extern const char digits[];
@@ -57,3 +62,17 @@ void console::put_hex(T x)
 	message[chars] = 0;
 	puts(message);
 }
+
+template <typename T>
+void console::put_dec(T x)
+{
+	static const int chars = sizeof(x) * 3;
+	char message[chars + 1];
+	char *p = message + chars;
+	*p-- = 0;
+	do {
+		*p-- = digits[x % 10];
+		x /= 10;
+	} while (x != 0);
+	puts(++p);
+}
diff --git a/src/modules/main/util.cpp b/src/modules/main/util.cpp
new file mode 100644
index 0000000..662cc5c
--- /dev/null
+++ b/src/modules/main/util.cpp
@@ -0,0 +1,29 @@
+#include "console.h"
+#include "util.h"
+
+[[noreturn]] void
+__kernel_assert(const char *file, unsigned line, const char *message)
+{
+	console *cons = console::get();
+	if (cons) {
+		cons->set_color(9 , 0);
+		cons->puts("\n\n  ERROR: ");
+		cons->puts(file);
+		cons->puts(":");
+		cons->put_dec(line);
+		cons->puts(":  ");
+		cons->puts(message);
+	}
+
+	__asm__ __volatile__( 
+		"movq %0, %%r8;"
+		"movq %1, %%r9;"
+		"movq %2, %%r10;"
+		"movq $0, %%rdx;"
+		"divq %%rdx;"
+		:
+		: "r"((uint64_t)line), "r"(file), "r"(message)
+		: "rax", "rdx", "r8", "r9", "r10");
+
+	while (1);
+}
diff --git a/src/modules/main/util.h b/src/modules/main/util.h
index 6cf2c32..162a045 100644
--- a/src/modules/main/util.h
+++ b/src/modules/main/util.h
@@ -7,3 +7,7 @@ struct coord {
 	coord(T x, T y) : x(x), y(y) {}
 	T size() const { return x * y; }
 };
+
+[[noreturn]] void __kernel_assert(const char *file, unsigned line, const char *message);
+
+#define kassert(stmt, message)  if(!(stmt)) { __kernel_assert(__FILE__, __LINE__, (message)); } else {}