diff --git a/usr/src/sp1/Makefile b/usr/src/sp1/Makefile
index a7e3496..fd4f73e 100644
--- a/usr/src/sp1/Makefile
+++ b/usr/src/sp1/Makefile
@@ -1,4 +1,3 @@
-#!/bin/sh
 #
 # Copyright (c) 2026, Mirocom Laboratories
 # All rights reserved.
@@ -11,7 +10,11 @@
 #
 
 .PHONY: all
-all: $(ARCH)
+all: common $(ARCH)
+
+.PHONY: common
+common:
+	cd common; $(MAKE)
 
 .PHONY: $(ARCH)
 $(ARCH):
diff --git a/usr/src/sp1/amd64/Makefile b/usr/src/sp1/amd64/Makefile
index 6cfd22f..b6103a4 100644
--- a/usr/src/sp1/amd64/Makefile
+++ b/usr/src/sp1/amd64/Makefile
@@ -11,8 +11,7 @@
 
 ASMFILES = $(shell find . -name "*.S")
 ASMOFILES = $(ASMFILES:.S=.S.o)
-
-MISC_OFILES = $(shell find ../../ -name "*.o")
+MISC_OFILES = $(shell find ../common -name "*.o")
 
 CC = 				\
 	../../../../$(SYS_CC)
@@ -25,7 +24,11 @@ CFLAGS = 			\
 
 .PHONY: all
 all: $(ASMOFILES)
-	$(LD) -Tconf/link.ld $(MISC_OFILES) -o ../../../../sp1.sys
+	$(LD) 			   \
+		-Tconf/link.ld \
+		$(MISC_OFILES) \
+		$(ASMOFILES)   \
+		-o ../../../../sp1.sys
 
 %.S.o: %.S
 	$(CC) -c $(CFLAGS) $< -o $@
diff --git a/usr/src/sp1/amd64/cpu/locore.S b/usr/src/sp1/amd64/cpu/locore.S
index 0bfde71..dcea44c 100644
--- a/usr/src/sp1/amd64/cpu/locore.S
+++ b/usr/src/sp1/amd64/cpu/locore.S
@@ -11,11 +11,13 @@
 
     .text
     .globl _start
+    .extern main
 _start:
     cli
     cld
 
     xor %rbp, %rbp
+    call main
 
     cli
 1:  hlt
diff --git a/usr/src/sp1/common/Makefile b/usr/src/sp1/common/Makefile
new file mode 100644
index 0000000..181a6bf
--- /dev/null
+++ b/usr/src/sp1/common/Makefile
@@ -0,0 +1,28 @@
+#
+# Copyright (c) 2026, Mirocom Laboratories
+# All rights reserved.
+#
+# The following sources are CONFIDENTIAL and PROPRIETARY
+# property of Mirocom Laboratories. Unauthorized copying,
+# use, distrubution or modification of this file, in whole
+# and in part, is strictly prohibited without the prior written
+# consent from Mirocom Laboratories.
+#
+
+CFILES = $(shell find os/ -name "*.c")
+OFILES = $(CFILES:.c=.o)
+
+CC = ../../../../$(SYS_CC)
+
+CFLAGS = 			\
+	$(SYS_CFLAGS)   \
+	-D_KERNEL		\
+	-MMD			\
+	-DPRINTF_DISABLE_SUPPORT_PTRDIFF_T \
+	-DPRINTF_DISABLE_SUPPORT_FLOAT
+
+.PHONY: all
+all: $(OFILES)
+
+%.o: %.c
+	$(CC) -c $< $(CFLAGS) -o $@
diff --git a/usr/src/sp1/common/os/main.c b/usr/src/sp1/common/os/main.c
new file mode 100644
index 0000000..f24f343
--- /dev/null
+++ b/usr/src/sp1/common/os/main.c
@@ -0,0 +1,15 @@
+/*
+ * Copyright (c) 2026, Mirocom Laboratories
+ * All rights reserved.
+ *
+ * The following sources are CONFIDENTIAL and PROPRIETARY
+ * property of Mirocom Laboratories. Unauthorized copying,
+ * use, distribution or modification of this file, in whole
+ * and in part, is strictly prohibited without the prior written
+ * consent from Mirocom Laboratories.
+ */
+
+void
+main(void)
+{
+}