diff --git a/.gitmodules b/.gitmodules
index 3384d54..4c94f47 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -4,3 +4,6 @@
 [submodule "linux-brain"]
 	path = linux-brain
 	url = https://github.com/brain-hackers/linux-brain
+[submodule "nkbin_maker"]
+	path = nkbin_maker
+	url = https://github.com/brain-hackers/nkbin_maker.git
diff --git a/Makefile b/Makefile
index 2578cc2..1c43f25 100644
--- a/Makefile
+++ b/Makefile
@@ -60,10 +60,17 @@ lbuild:
 uuu:
 	sudo uuu ./u-boot-brain/u-boot.sb
 
+.PHONY:
+nkbin-maker:
+	make -C ./nkbin_maker
+
+.PHONY:
+nk.bin:
+	./nkbin_maker/bsd-ce ./u-boot-brain/u-boot.bin
+
 debian:
 	mkdir debian
 	sudo debootstrap --arch=armel --foreign buster debian/
 	sudo cp /usr/bin/qemu-arm-static debian/usr/bin/
 	sudo cp setup_debian.sh debian/
 	sudo chroot debian /setup_debian.sh
-
diff --git a/README.md b/README.md
index 4588557..9e179a2 100644
--- a/README.md
+++ b/README.md
@@ -3,7 +3,7 @@ buildbrain
 
 This repository includes:
 
- - linux-brain and u-boot-brain as submodules
+ - linux-brain, u-boot-brain and nkbin_maker as submodules
  - Useful build targets in Makefile
  - r3build.toml to watch changes that occur in submodules
 
@@ -53,6 +53,18 @@ Build and inject U-Boot
 3. To inject the executable into i.MX283 in recovery mode, run `make uuu`.
 
 
+Build and make NK.bin
+-----------------------
+
+1. Run `make udefconfig` to generate `.config`.
+
+2. Run `make ubuild` to build whole repository and generate `u-boot.bin`.
+
+3. To make `nk.bin`, run `make nkbin`.
+
+    - nkbin_maker packs `u-boot.bin` into `nk.bin`.
+
+
 Build Linux
 -----------
 
diff --git a/nkbin_maker b/nkbin_maker
new file mode 160000
index 0000000..4a97a4e
--- /dev/null
+++ b/nkbin_maker
@@ -0,0 +1 @@
+Subproject commit 4a97a4e8074cec12ac8989bcfcab9b9f7d47156d