diff --git a/boot/common/fat12.inc b/boot/common/fat12.inc
index 39ec1d8..48db169 100644
--- a/boot/common/fat12.inc
+++ b/boot/common/fat12.inc
@@ -15,7 +15,7 @@ struc fat_bpb
 	.sects_per_track  dw ?
 	.heads_per_cyl    dw ?
 }
-defn fat_bpb
+DEFN fat_bpb
 
 	;; Struct: fat_entry
 struc fat_entry
@@ -33,7 +33,7 @@ struc fat_entry
 	.start         dw ?
 	.size          dd ?
 }
-defn fat_entry
+DEFN fat_entry
 
 	;; Constants: Attributes
 	;;  ATTR_READ_ONLY - Read-only
diff --git a/boot/common/macro.inc b/boot/common/macro.inc
index 1218de9..d24d2aa 100644
--- a/boot/common/macro.inc
+++ b/boot/common/macro.inc
@@ -1,9 +1,9 @@
 	;; File: macro.inc
 
-	;; Macro: defn name
-macro defn name
-{
-	virtual at 0
-		name name
-	end virtual
+	;; Macro: DEFN name
+macro DEFN x {
+virtual at 0
+  x x
+  sizeof.#x:
+end virtual
 }
diff --git a/boot/common/mbr.inc b/boot/common/mbr.inc
index 1c4e01d..3c1e939 100644
--- a/boot/common/mbr.inc
+++ b/boot/common/mbr.inc
@@ -10,6 +10,6 @@ struc Partition
 	.lba       dd ?
 	.sectors   dd ?
 }
-defn Partition
+DEFN Partition
 
 
diff --git a/boot/efi/uefi.inc b/boot/efi/uefi.inc
index 5bdcc4d..78cf2bc 100644
--- a/boot/efi/uefi.inc
+++ b/boot/efi/uefi.inc
@@ -80,7 +80,7 @@ struc EFI_TIME
 	.Daylight   UINT8
 	.Pad2       UINT8
 }
-defn EFI_TIME
+DEFN EFI_TIME
 
 struc EFI_TABLE_HEADER
 {
@@ -90,7 +90,7 @@ struc EFI_TABLE_HEADER
 	.CRC32       UINT32
 	.Reserved    UINT32
 }
-defn EFI_TABLE_HEADER
+DEFN EFI_TABLE_HEADER
 
 	;; ========================================================================
 	;; EFI_SYSTEM_TABLE
@@ -131,7 +131,7 @@ struc EFI_SYSTEM_TABLE
 	.NumberOfTableEntries UINTN
 	.ConfigurationTable   UINTPTR
 }
-defn EFI_SYSTEM_TABLE
+DEFN EFI_SYSTEM_TABLE
 
 	;; ========================================================================
 	;; EFI_BOOT_SERVICES
@@ -210,7 +210,7 @@ struc EFI_BOOT_SERVICES
 	.SetMem        UINTPTR
 	.CreateEventEx UINTPTR
 }
-defn EFI_BOOT_SERVICES
+DEFN EFI_BOOT_SERVICES
 
 	;; ========================================================================
 	;; EFI_RUNTIMES_SERVICES
@@ -269,7 +269,7 @@ struc EFI_LOADED_IMAGE_PROTOCOL
 	.ImageDataType   UINT32
 	.Unload          UINTPTR
 }
-defn EFI_LOADED_IMAGE_PROTOCOL
+DEFN EFI_LOADED_IMAGE_PROTOCOL
 
 	;; ========================================================================
 	;; EFI_DEVICE_PATH_PROTOCOL
@@ -282,7 +282,7 @@ struc EFI_DEVICE_PATH_PROTOCOL
 	.SubType UINT8
 	.Length  db 2 dup(?)
 }
-defn EFI_DEVICE_PATH_PROTOCOL
+DEFN EFI_DEVICE_PATH_PROTOCOL
 
 	;; ========================================================================
 	;; EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL
@@ -302,7 +302,7 @@ struc EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL
 	.EnableCursor      UINTPTR
 	.Mode              UINTPTR
 }
-defn EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL
+DEFN EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL
 
 struc SIMPLE_TEXT_OUTPUT_MODE
 {
@@ -350,7 +350,7 @@ struc EFI_LOAD_FILE_PROTOCOL
 {
 	.LoadFile UINTPTR
 }
-defn EFI_LOAD_FILE_PROTOCOL
+DEFN EFI_LOAD_FILE_PROTOCOL
 
 
 	;; ========================================================================
@@ -372,7 +372,7 @@ struc EFI_SIMPLE_FILE_SYSTEM_PROTOCOL
 	.Revision   UINT64
 	.OpenVolume UINTPTR
 }
-defn EFI_SIMPLE_FILE_SYSTEM_PROTOCOL
+DEFN EFI_SIMPLE_FILE_SYSTEM_PROTOCOL
 
 	;; ========================================================================
 	;; EFI_FILE_PROTOCOL
@@ -400,7 +400,7 @@ struc EFI_FILE_PROTOCOL
 	.WriteEx     UINTPTR
 	.FlushEx     UINTPTR
 }
-defn EFI_FILE_PROTOCOL
+DEFN EFI_FILE_PROTOCOL
 
 	; Open Mode
 EFI_FILE_MODE_READ   = 0x0000000000000001
diff --git a/boot/loader/Makefile b/boot/loader/Makefile
index 43d6f7a..b164565 100644
--- a/boot/loader/Makefile
+++ b/boot/loader/Makefile
@@ -10,7 +10,8 @@ LOADER_SRCS	= loader.asm \
 				memory.inc \
 				logger.inc \
 				a20.inc \
-				multiboot.inc
+				multiboot.inc \
+				stpdfs.inc
 
 .PHONY: all
 all: $(TARGET)
diff --git a/boot/loader/fat.inc b/boot/loader/fat.inc
index 3bad234..213e163 100644
--- a/boot/loader/fat.inc
+++ b/boot/loader/fat.inc
@@ -2,6 +2,7 @@
 
 include '../common/fat12.inc'
 
+	;; Function: fat_read_bpb
 fat_read_bpb:
 	mov ax, DISK_BUFFER/0x10
 	mov es, ax
diff --git a/boot/loader/loader.asm b/boot/loader/loader.asm
index 31f2a79..fc3c3a8 100644
--- a/boot/loader/loader.asm
+++ b/boot/loader/loader.asm
@@ -76,9 +76,23 @@ _start:
 	cmp dword [DISK_BUFFER], STPDFS_MAGIC
 	jne  .fat_fallback
 
+	mov si, szMsgStpdFSFound
+	call bios_log
+
+	call stpdfs_load_rootdir
+
+	mov si, szKernelStpdfsFile
+	call stpdfs_search
+
+
+	jmp .skip_fat
+
 	; fallback to fat12	
 	; for now fat12 is asumed
 .fat_fallback:
+	mov si, szMsgFatFallback
+	call bios_log
+
 	; get bpb
 	call fat_read_bpb
 
@@ -112,6 +126,8 @@ _start:
 	xor bx, bx
 	call fat_load_binary
 
+.skip_fat:
+
 	; fetch memory map from bios
 	call memory_get_map
 	jc .error_memory
@@ -156,6 +172,7 @@ _start:
 	include 'a20.inc'
 	include '../common/bios.inc'
 	include 'fat.inc'
+	include 'stpdfs.inc'
 	include 'disk.inc'
 	include 'logger.inc'
 	include 'memory.inc'
@@ -173,6 +190,9 @@ uKernelSize        dd 0
 
 szMsgStage2        db "StupidOS Loader", 0
 szKernelFile       db "VMSTUPIDSYS", 0
+szKernelStpdfsFile db "vmstupid.sys", 0
+szMsgStpdFSFound   db "StupidFS found", 0
+szMsgFatFallback   db "Fallback to FATFS", 0
 szMsgKernelFound   db "Kernel found, size: %x", 0
 szMsgErrorA20      db "ERROR: can't enable a20 line", 0
 szMsgErrorMemory   db "ERROR: can't detect available memory", 0
diff --git a/boot/loader/multiboot.inc b/boot/loader/multiboot.inc
index cec1cd0..f4db7e2 100644
--- a/boot/loader/multiboot.inc
+++ b/boot/loader/multiboot.inc
@@ -82,7 +82,7 @@ struc MultibootData
         .fb_type   db ?
         .fb_misc   dw 3 dup ?
 }
-defn MultibootData
+DEFN MultibootData
 
 MULTIBOOT_DATA_MEM             = 0x0001
 MULTIBOOT_DATA_BOOTDEV         = 0x0002
@@ -101,7 +101,7 @@ struc MultibootMMap
         .length dq ?
         .type   dd ?
 }
-defn MultibootMMap
+DEFN MultibootMMap
 
 MULTIBOOT_MEMORY_AVAILABLE = 0x1
 MULTIBOOT_MEMORY_RESERVED  = 0x2
@@ -116,4 +116,4 @@ struc MultibootModule
 	.cmdline   dd ?
 	.pad       dd ?
 }
-defn MultibootModule
+DEFN MultibootModule
diff --git a/boot/loader/stpdfs.inc b/boot/loader/stpdfs.inc
new file mode 100644
index 0000000..3783a8c
--- /dev/null
+++ b/boot/loader/stpdfs.inc
@@ -0,0 +1,55 @@
+STPDFS_NAME_MAX = 28
+
+	;; Struct: inode
+struc inode {
+	.inode   dw ?
+	.nlink   dw ?
+	.uid     dw ?
+	.gid     dw ?
+	.flags   dw ?
+	.size    dd ?
+	.zones   dd 10 dup(?)
+	.actime  dq ?
+	.modtime dq ?
+}
+DEFN inode
+
+	;; Struct: dirent
+struc dirent {
+	.inum dd ?
+	.name db STPDFS_NAME_MAX dup(?)
+}
+DEFN dirent
+
+	;; Function: stpdfs_load_rootdir
+	;;
+	;; Out:
+stpdfs_load_rootdir:
+	; read first inode
+	mov ax, DISK_BUFFER/0x10
+	mov es, ax
+	mov ax, 2
+	mov cx, 1
+	xor bx, bx
+	call disk_read_sectors
+	
+	; root dir is inode 1
+	mov dword eax, [DISK_BUFFER + sizeof.inode * 2 + inode.size]
+
+
+
+	ret
+
+	;; Function: stpdfs_search
+	;;
+	;; In:
+	;;    SI - filename
+	;;
+stpdfs_search:
+	clc	; clear carry flag
+
+
+	ret
+
+stpdfs_copy_data:
+	ret