diff --git a/sdk/Makefile b/sdk/Makefile
index 08cfca9..8ede995 100644
--- a/sdk/Makefile
+++ b/sdk/Makefile
@@ -15,7 +15,7 @@
 #   <BUILD> is one of: mingw32, mingw64.
 #   <FB_FLAG> is 1 to force build, otherwise do not (default).
 #   <FC_FLAG> is 1 to force clean, otherwise do not (default).
-#   <TARGET> is one of values of TOOLS variable (see below).
+#   <TARGET> is one of: sjasmplus, z88dk, zx7b, tools
 #
 # Notes:
 #   BUILD, FORCEBUILD, FORCECLEAN variables may be set in user's environment.
@@ -43,31 +43,17 @@ export BUILD
 export FORCEBUILD
 export FORCECLEAN
 
-SJASMPLUS	:= sjasmplus$(EXECEXT)
-ZX7B		:= zx7b$(EXECEXT)
-BIN2HEX		:= bin2hex$(EXECEXT)
-FCUT		:= fcut$(EXECEXT)
-FPAD		:= fpad$(EXECEXT)
-FPOKE		:= fpoke$(EXECEXT)
-GENROM		:= GenRom$(EXECEXT)
-ADDITEM		:= AddItem$(EXECEXT)
-
-TOOLS:=\
- bin/$(SJASMPLUS) \
- bin/$(ZX7B) \
- bin/$(BIN2HEX) \
- bin/$(FCUT) \
- bin/$(FPAD) \
- bin/$(FPOKE) \
- bin/$(GENROM) \
- bin/$(ADDITEM)
-
 .PHONY: all
-all: $(TOOLS)
+all: sjasmplus z88dk zx7b tools
 
-$(TOOLS): | src/Makefile
-	$(MAKE) -w -C src ../bin/$(@F)
+.PHONY: sjasmplus z88dk
+sjasmplus z88dk: | src
+	$(MAKE) -w -C $| external-$@
 
-.PHONY: clean
-clean: | src/Makefile
-	$(MAKE) -w -C src clean
+.PHONY: zx7b tools
+zx7b tools: | src
+	$(MAKE) -w -C $| local-$@
+
+.PHONY: clean dist-clean
+clean dist-clean: | src
+	$(MAKE) -w -C $| $@
diff --git a/sdk/README.md b/sdk/README.md
index 8bf4ae5..7c10fe5 100644
--- a/sdk/README.md
+++ b/sdk/README.md
@@ -8,11 +8,14 @@ No one yet.
 
 # License
 
-This document is under [GNU FDL-1.3 or later](http://www.gnu.org/licenses/fdl-1.3.html) license.
+This document is under [GNU FDL-1.3 or later](https://spdx.org/licenses/GFDL-1.3-or-later.html) license.  
+SJAsmPlus Z80 Assembler is distributed under [zlib](https://spdx.org/licenses/Zlib.html) license.  
+z88dk is distributed under [Clarified Artistic](https://spdx.org/licenses/ClArtistic.html) license.
 
 # 1. General information
 
-The source code of all tools is in `src` directory. All compiled binaries are placed in `bin` directory.
+The source code of local tools is in `src` directory. Compiled binaries of them are placed in `bin` directory.  
+Downloaded tools are placed in sub-directories of `src`. See Makefiles for details.
 
 ## 1.1. Copyright and licensing information for files
 
@@ -28,15 +31,22 @@ Check it out by using this [reuse-tool](https://github.com/fsfe/reuse-tool).
 
 Open terminal and type:
 
-```bash
-# apt install -y build-essential git cmake libboost-all-dev
+```
+# apt install -y build-essential git
 ```
 
 **NOTE**: here the first symbol "#" means that the following command must be run as *root* or using `sudo` utility.
 
+Additional packages for targets:
+
+Target | Packages
+----|----
+`sjasmplus` | cmake libboost-all-dev libxml2-dev
+`z88dk` | dos2unix libboost-all-dev texinfo texi2html libxml2-dev subversion bison flex zlib1g-dev m4
+
 To use cross-compilation for Windows platform install *mingw-w64* package:
 
-```bash
+```
 # apt install -y mingw-w64
 ```
 
@@ -52,48 +62,55 @@ Now `zxuno` sub-directory is the ZX-Uno project's root directory and all actions
 
 ## 2.2. Build tools
 
-Go to the project's root directory and type one of the following commands:
+Go to the project's root directory, enter `sdk` sub-directory and type one of the following commands:
 
-Command | Target
+Command | Description
 ----|----
-`make` | all tools
-`make bin/sjasmplus` | **sjasmplus**
-`make bin/zx7b` | **zx7b**
-`make bin/bin2hex` | **bin2hex**
-`make bin/fcut` | **fcut**
-`make bin/fpad` | **fpad**
-`make bin/fpoke` | **fpoke**
-`make bin/GenRom` | **GenRom**
-`make bin/AddItem` | **AddItem**
+`make` | Build all tools from sources
+`make <TARGET>` | Build only the TARGET from sources
+`make BUILD=<BUILD>` | Cross-build all tools from sources for Windows platfowm
+`make BUILD=<BUILD> <TARGET>` | Cross-build only the TARGET from sources for Windows platfowm
 
-To build using MinGW add this parameter for `make` tool:
+where:
 
-Parameter | Target system
+Value of `TARGET` | Origin | Description
+----|----|----
+`sjasmplus` | downloaded | SJAsmPlus Z80 Assembler
+`z88dk` | downloaded | z88dk
+`zx7b` | `src/zx7b` | zx7b
+`tools` | `src/tools` | tools
+
+Value of `BUILD` | Target system
 ----|----
-`BUILD=mingw32` | Windows with i686 architecture (32-bits)
-`BUILD=mingw64` | Windows with AMD64 architecture (64-bits)
+`mingw32` | Windows with i686 architecture (32-bits)
+`mingw64` | Windows with AMD64 architecture (64-bits)
 
-Remember to specify proper file extension (`.exe`) for target when building with MinGW. Example:
+Example:
 
 ```bash
-make BUILD=mingw64 bin/fcut.exe bin/fpad.exe bin/fpoke.exe
+make BUILD=mingw64 tools
 ```
 
-Then you may use `strip` tool to strip debug information from file and thus shrink file's size:
+Then you may use `strip` tool to strip debug information from file and thus shrink file's size. Example:
 
 ```bash
-strip bin/fcut.exe bin/fpad.exe bin/fpoke.exe
+strip bin/*.exe
 ```
 
 ## 2.3. Clean tools
 
-To clean everything type:
+Go to the project's root directory, enter `sdk` sub-directory and type one of the following commands:
 
-```bash
-make clean
-```
+Command | Description
+----|----
+`make clean` | clean after compilation from sources
+`make dist-clean` | acts like `clean` but also removes temporary and downloaded files
+`make BUILD=<BUILD> clean` | clean after compilation from sources for Windows platform
+`make BUILD=<BUILD> dist-clean` | acts like `clean` for Windows platform but also removes temporary and downloaded files
 
-To clean MinGW builds use appropriate `BUILD` parameter as described in [2.2](#22-build-tools). Example:
+Value of `BUILD` is described in [2.2](#22-build-tools).
+
+Example:
 
 ```bash
 make BUILD=mingw64 clean
@@ -138,38 +155,81 @@ This has the same behavior as the inclusion of `common.mk` file in a Makefile.
 
 # 3. Using SDK in GNU environment on Windows
 
-**NOTE**: *by default* compilation of the following tools:
+## 3.1. Prepare a build environment
 
-* sjasmplus
-* zx7b
-* bin2hex
-* fcut
-* fpad
-* fpoke
-* GenRom
-* AddItem
+### 3.1.1. Setup Cygwin
 
-on Windows platform is disabled right now because of presence of precompiled binaries of them in repository.
-*By default* they are not deleted when cleaning.
+Download and run [Cygwin](https://cygwin.com/) GUI installer for Windows, either [32 bit](https://cygwin.com/setup-x86.exe) or [64 bit](https://cygwin.com/setup-x86_64.exe) version. See [Chapter 2. Setting Up Cygwin](https://cygwin.com/cygwin-ug-net/setup-net.html) for more information.
 
-## 3.1. Build tools
+Install the following packages in Cygwin:
 
-The building process is similar to one for GNU on Linux, FreeBSD etc.
-See [2.2](#22-build-tools) with addition that you should provide correct target name (specify file extension `.exe`) and also specify parameter `FORCEBUILD=1`.
+Target | Dependencies
+----|----
+all targets | bash git make wget unzip p7zip
+`sjasmplus` | gcc-g++ cmake libboost-devel
+`z88dk` | mingw64-i686-gcc-core mingw64-i686-libxml2 patch
+`zx7b` | gcc-core
+`tools` | gcc-core
 
-## 3.2. Clean tools
+**HINT**: you can install *Midnight Commander* (`mc` package). It will help you to navigate through filesystem.
 
-The cleaning process is similar to one for GNU on Linux, FreeBSD etc.
-See [2.3](#23-clean-tools) with addition that you should specify parameter `FORCECLEAN=1`.
+To open Cygwin terminal just click on it's icon on desktop. This will open a Bash shell in a GNU environment.
 
-## 3.3. Tools usage
+### 3.1.2. Clone repository
 
-### 3.3.1. In Makefiles
+The cloning is described in [2.1.2](#212-clone-repository).
+
+## 3.2. Build tools
+
+Go to the project's root directory, enter `sdk` sub-directory and type one of the following commands:
+
+Command | Description
+----|----
+`make` | Quick setup of all tools
+`make <TARGET>` | Qucik setup of the TARGET only
+`make FORCEBUILD=1` | Build all tools from sources
+`make FORCEBUILD=1 <TARGET>` | Build only the TARGET from sources
+
+where:
+
+Value of `TARGET` | Origin | Quick setup | Build from sources
+----|----|----|----
+`sjasmplus` | downloaded | available | available
+`z88dk` | downloaded | available | available
+`zx7b` | `src/zx7b` | N/A | available
+`tools` | `src/tools` | N/A | available
+
+Then you may use `strip` tool to strip debug information from file and thus shrink file's size. Example:
+
+```bash
+strip bin/*.exe
+```
+
+## 3.3. Clean tools
+
+Go to the project's root directory, enter `sdk` sub-directory and type one of the following commands:
+
+Command | Description
+----|----
+`make clean` | removes downloaded precompiled binaries only
+`make dist-clean` | acts as `clean` but also removes temporary and downloaded files
+`make FORCECLEAN=1 clean` | clean after compilation from sources
+`make FORCECLEAN=1 dist-clean` | acts as forced `clean` but also removes temporary and downloaded files
+
+Example:
+
+```bash
+make FORCECLEAN=1 clean
+```
+
+## 3.4. Tools usage
+
+### 3.4.1. In Makefiles
 
 The usage is similar to one for GNU on Linux, FreeBSD etc.
 See [2.4.1](#241-in-makefiles).
 
-### 3.3.2. In Bash scripts
+### 3.4.2. In Bash scripts
 
 The usage is similar to one for GNU on Linux, FreeBSD etc.
 See [2.4.2](#242-in-bash-scripts).
diff --git a/sdk/common.mk b/sdk/common.mk
index 1504d52..c1ea14b 100644
--- a/sdk/common.mk
+++ b/sdk/common.mk
@@ -11,23 +11,33 @@
 ifndef ZXUNOSDK
 
 ZXUNOSDK	:= $(patsubst %/,%,$(abspath $(dir $(lastword $(MAKEFILE_LIST)))))
-PATH		:= $(ZXUNOSDK)/bin:$(PATH)
+Z88DK		:= $(ZXUNOSDK)/src/z88dk
+ZCCCFG		:= $(Z88DK)/lib/config
+PATH		:= $(ZXUNOSDK)/bin:$(Z88DK)/bin:$(PATH)
+
+# Fix paths under Cygwin for z88dk on Windows
+ifeq ($(OS),Windows_NT)
+ifeq ($(shell echo $$OSTYPE),cygwin)
+ZCCCFG		:= $(shell cygpath -m $(ZCCCFG))
+endif
+endif
 
 export ZXUNOSDK
+export ZCCCFG
 export PATH
 
 endif
 
 ifeq ($(OS),Windows_NT)
-EXECEXT		:= .exe
+EXESUFFIX	:= .exe
 else
-EXECEXT		:=
+EXESUFFIX	:=
 endif
 
 ifeq ($(BUILD),mingw32)
 CC		:= i686-w64-mingw32-gcc
-EXECEXT		:= .exe
+EXESUFFIX	:= .exe
 else ifeq ($(BUILD),mingw64)
 CC		:= x86_64-w64-mingw32-gcc
-EXECEXT		:= .exe
+EXESUFFIX	:= .exe
 endif
diff --git a/sdk/setvars.bat b/sdk/setvars.bat
index ffe8fac..be3b30a 100644
--- a/sdk/setvars.bat
+++ b/sdk/setvars.bat
@@ -6,4 +6,6 @@ rem SPDX-License-Identifier: GPL-3.0-or-later
 if not x%ZXUNOSDK% == x exit /b
 set ZXUNOSDK=%~dp0
 set ZXUNOSDK=%ZXUNOSDK:~0,-1%
-set PATH=%ZXUNOSDK%\bin;%PATH%
+set Z88DK=%ZXUNOSDK%\src\z88dk
+set ZCCCFG=%Z88DK%\lib\config
+set PATH=%ZXUNOSDK%\bin;%Z88DK%\bin;%PATH%
diff --git a/sdk/setvars.sh b/sdk/setvars.sh
index 9a41831..edbaf59 100644
--- a/sdk/setvars.sh
+++ b/sdk/setvars.sh
@@ -5,6 +5,13 @@
 
 if [[ "x$ZXUNOSDK" == x ]]; then
 	ZXUNOSDK=$(dirname $(realpath "$BASH_SOURCE"))
-	PATH=$ZXUNOSDK/bin:$PATH
+	Z88DK=$ZXUNOSDK/src/z88dk
+	ZCCCFG=$Z88DK/lib/config
+	PATH=$ZXUNOSDK/bin:$Z88DK/bin:$PATH
+	# Fix paths under Cygwin for z88dk on Windows
+	if [[ x$OS == xWindows_NT -a x$OSTYPE == xcygwin ]]; then
+		ZCCCFG=`cygpath -m $ZCCCFG`
+	fi
 	export ZXUNOSDK
+	export ZCCCFG
 fi
diff --git a/sdk/src/.gitignore b/sdk/src/.gitignore
index 43b40b3..e1b2444 100644
--- a/sdk/src/.gitignore
+++ b/sdk/src/.gitignore
@@ -3,3 +3,14 @@
 # SPDX-License-Identifier: CC0-1.0
 
 sjasmplus
+sjasmplus-src.tgz
+sjasmplus-src.tgz.sha256
+sjasmplus-win32.7z
+sjasmplus-win32.7z.sha256
+sjasmplus-win64.7z
+sjasmplus-win64.7z.sha256
+z88dk
+z88dk-src.tgz
+z88dk-src.tgz.sha256
+z88dk-win32.zip
+z88dk-win32.zip.sha256
diff --git a/sdk/src/Makefile b/sdk/src/Makefile
index babd03a..e185d53 100644
--- a/sdk/src/Makefile
+++ b/sdk/src/Makefile
@@ -9,117 +9,288 @@
 # Build:
 #   make [BUILD=<BUILD>] [FORCEBUILD=<FB_FLAG>] [<TARGET>]
 # Clean:
-#   make [BUILD=<BUILD>] [FORCECLEAN=<FC_FLAG>] clean
+#   make [BUILD=<BUILD>] [FORCECLEAN=<FC_FLAG>] clean|dist-clean
 #
 # where:
 #   <BUILD> is one of: mingw32, mingw64.
 #   <FB_FLAG> is 1 to force build, otherwise do not (default).
 #   <FC_FLAG> is 1 to force clean, otherwise do not (default).
-#   <TARGET> is one of values of TOOLS variable (see below).
+#   <TARGET> is one of:
+#     * external-sjasmplus
+#     * external-z88dk
+#     * local-zx7b
+#     * local-tools
 #
 # Notes:
 #   BUILD, FORCEBUILD, FORCECLEAN variables may be set in user's environment.
 
 include ../common.mk
 
-SJASMPLUS	:= sjasmplus$(EXECEXT)
-ZX7B		:= zx7b$(EXECEXT)
-BIN2HEX		:= bin2hex$(EXECEXT)
-FCUT		:= fcut$(EXECEXT)
-FPAD		:= fpad$(EXECEXT)
-FPOKE		:= fpoke$(EXECEXT)
-GENROM		:= GenRom$(EXECEXT)
-ADDITEM		:= AddItem$(EXECEXT)
-
-TOOLS:= \
- ../bin/$(SJASMPLUS) \
- ../bin/$(ZX7B) \
- ../bin/$(BIN2HEX) \
- ../bin/$(FCUT) \
- ../bin/$(FPAD) \
- ../bin/$(FPOKE) \
- ../bin/$(GENROM) \
- ../bin/$(ADDITEM)
+INSTALLDIR=../bin
 
 .PHONY: all
-all: $(TOOLS)
+all:\
+ external-sjasmplus\
+ external-z88dk\
+ local-zx7b\
+ local-tools
+
+_DoBuild:=1
+_UsePrecompiledOnWindows:=0
 
 ifeq ($(OS),Windows_NT)
-ifeq ($(FORCEBUILD),1)
-_DoBuild:=1
-else
+ifneq ($(FORCEBUILD),1)
 _DoBuild:=0
+_UsePrecompiledOnWindows:=1
 endif
-else
-_DoBuild:=1
 endif
 
-ifeq ($(OS),Windows_NT)
-ifeq ($(FORCECLEAN),1)
 _DoClean:=1
-else
+ifeq ($(OS),Windows_NT)
+ifneq ($(FORCECLEAN),1)
 _DoClean:=0
 endif
-else
-_DoClean:=1
 endif
 
+# sjasmplus
+
+.PHONY: external-sjasmplus clean-sjasmplus
+
+external-sjasmplus: $(INSTALLDIR)/sjasmplus$(EXESUFFIX)
+
 ifeq ($(_DoBuild),1)
-../bin/$(SJASMPLUS): sjasmplus/build/$(SJASMPLUS)
+
+$(INSTALLDIR)/sjasmplus$(EXESUFFIX): sjasmplus/build/sjasmplus$(EXESUFFIX)
 	cp $< $@
 
-sjasmplus/build/$(SJASMPLUS): | sjasmplus sjasmplus.mk
+sjasmplus/build/sjasmplus$(EXESUFFIX): | sjasmplus/.extracted sjasmplus.mk
 	$(MAKE) -w -C sjasmplus -f ../sjasmplus.mk
 
-sjasmplus:
-	wget -c https://github.com/sjasmplus/sjasmplus/archive/refs/tags/20190306.1.tar.gz -O sjasmplus.tgz
-	echo 'f3f6d28af19880ed2cb427b6b427e9bd42371929c7d263dac840fb71de1302d6  sjasmplus.tgz' >sjasmplus.sha256sum
-	sha256sum -c sjasmplus.sha256sum
-	rm -f sjasmplus.sha256sum
-	tar -xzf sjasmplus.tgz
-	mv sjasmplus-20190306.1 sjasmplus
-	rm -f sjasmplus.tgz
+sjasmplus/.extracted: sjasmplus-src.tgz
+	echo 'f3f6d28af19880ed2cb427b6b427e9bd42371929c7d263dac840fb71de1302d6  $<' >$<.sha256
+	sha256sum -c $<.sha256
+	rm -f $<.sha256
+	rm -rf $(@D) sjasmplus-20190306.1
+	tar -xzf $<
+	mv sjasmplus-20190306.1 $(@D)
+	touch $@
 
-../bin/$(ZX7B): zx7b/$(ZX7B)
+sjasmplus-src.tgz:
+	wget -c https://github.com/sjasmplus/sjasmplus/archive/refs/tags/20190306.1.tar.gz -O $@
+
+clean-sjasmplus:
+	if test -d sjasmplus; then $(MAKE) -w -C sjasmplus -f ../sjasmplus.mk clean; fi
+	rm -f $(INSTALLDIR)/sjasmplus$(EXESUFFIX)
+
+endif
+
+ifeq ($(_UsePrecompiledOnWindows),1)
+
+$(INSTALLDIR)/sjasmplus$(EXESUFFIX): sjasmplus/sjasmplus$(EXESUFFIX)
 	cp $< $@
 
-zx7b/$(ZX7B): | zx7b
+sjasmplus/sjasmplus$(EXESUFFIX): | sjasmplus/.extracted
+
+ifeq ($(PROCESSOR_ARCHITECTURE),AMD64)
+SJASMPLUS_ARCHIVE		:= sjasmplus-win64.7z
+SJASMPLUS_ARCHIVE_SHA256	:= ef352b50ce7c9e9971c6fc3143e378d3e9f4069f11eb0c33022195c6e9b34fcb
+else
+SJASMPLUS_ARCHIVE		:= sjasmplus-win32.7z
+SJASMPLUS_ARCHIVE_SHA256	:= c84731640930afc4f4cc3c0f30f891916b9b77d63dc0e4cfdcd226682b8545b1
+endif
+
+sjasmplus/.extracted: $(SJASMPLUS_ARCHIVE)
+	echo '$(SJASMPLUS_ARCHIVE_SHA256)  $<' >$<.sha256
+	sha256sum -c $<.sha256
+	rm -f $<.sha256
+	rm -rf $(@D)
+	7z x -bd -o$(@D) $<
+	touch $@
+
+sjasmplus-win32.7z:
+	wget -c https://github.com/sjasmplus/sjasmplus/releases/download/20190306.1/sjasmplus-win32-20190306.1.7z -O $@
+
+sjasmplus-win64.7z:
+	wget -c https://github.com/sjasmplus/sjasmplus/releases/download/20190306.1/sjasmplus-win64-20190306.1.7z -O $@
+
+clean-sjasmplus:
+	rm -rf sjasmplus
+	rm -f $(INSTALLDIR)/sjasmplus$(EXESUFFIX)
+
+endif
+
+.PHONY: dist-clean-sjasmplus
+dist-clean-sjasmplus:
+	rm -rf sjasmplus
+	rm -f $(INSTALLDIR)/sjasmplus$(EXESUFFIX)
+	rm -f\
+ sjasmplus-src.tgz\
+ sjasmplus-src.tgz.sha256\
+ sjasmplus-win32.7z\
+ sjasmplus-win32.7z.sha256\
+ sjasmplus-win64.7z\
+ sjasmplus-win64.7z.sha256
+
+# z88dk
+
+.PHONY: external-z88dk clean-z88dk
+
+Z88DK_TARGETS:=\
+ asmpp.pl\
+ sccz80$(EXESUFFIX)\
+ z80asm$(EXESUFFIX)\
+ z88dk-appmake$(EXESUFFIX)\
+ z88dk-basck$(EXESUFFIX)\
+ z88dk-copt$(EXESUFFIX)\
+ z88dk-dis$(EXESUFFIX)\
+ z88dk-dzx7$(EXESUFFIX)\
+ z88dk-font2pv1000$(EXESUFFIX)\
+ z88dk-lib$(EXESUFFIX)\
+ z88dk-ticks$(EXESUFFIX)\
+ z88dk-ucpp$(EXESUFFIX)\
+ z88dk-z80asm$(EXESUFFIX)\
+ z88dk-z80nm$(EXESUFFIX)\
+ z88dk-z80svg$(EXESUFFIX)\
+ z88dk-zcpp$(EXESUFFIX)\
+ z88dk-zobjcopy$(EXESUFFIX)\
+ z88dk-zpragma$(EXESUFFIX)\
+ z88dk-zx7$(EXESUFFIX)\
+ zcc$(EXESUFFIX)
+
+external-z88dk: z88dk/.done
+
+ifeq ($(_DoBuild),1)
+
+# Force Win32 build for Windows
+ifeq ($(OS),Windows_NT)
+export CC=i686-w64-mingw32-gcc
+endif
+
+z88dk/.done: | z88dk/.extracted z88dk.mk
+	$(MAKE) -w -C z88dk -f ../z88dk.mk
+	cd z88dk/bin && test x $(patsubst %,-a -x %,$(Z88DK_TARGETS))
+	touch $@
+
+z88dk/.extracted: z88dk-src.tgz
+	echo 'f3579ee59b4af552721173165af38223b115ccb67179e79d2f3c0ae64338dc7c  $<' >$<.sha256
+	sha256sum -c $<.sha256
+	rm -f $<.sha256
+	rm -rf z88dk
+	tar -xzf $<
+	patch -N -p0 -s <z88dk.patch || true
+	touch $@
+
+z88dk-src.tgz:
+	wget -c https://github.com/z88dk/z88dk/releases/download/v2.1/z88dk-src-2.1.tgz -O $@
+
+# This does not work:
+#clean-z88dk: | z88dk.mk
+#	if test -d z88dk; then $(MAKE) -w -C z88dk -f ../z88dk.mk clean && rm -f z88dk/.done; fi
+clean-z88dk:
+	rm -rf z88dk
+
+endif
+
+ifeq ($(_UsePrecompiledOnWindows),1)
+
+z88dk/.done: z88dk-win32.zip
+	echo 'f4abedfae429ea159e388b5c76758ace4dcb86e9a00dbd928862b0a30f6874d6  $<' >$<.sha256
+	sha256sum -c $<.sha256
+	rm -f $<.sha256
+	rm -rf z88dk
+	unzip -nq $<
+	touch $@
+
+z88dk-win32.zip:
+	wget -c https://github.com/z88dk/z88dk/releases/download/v2.1/z88dk-win32-2.1.zip -O $@
+
+clean-z88dk:
+	rm -rf z88dk
+
+endif
+
+.PHONY: dist-clean-z88dk
+dist-clean-z88dk:
+	rm -rf z88dk
+	rm -f\
+ z88dk-src.tgz\
+ z88dk-src.tgz.sha256\
+ z88dk-win32.zip\
+ z88dk-win32.zip.sha256
+
+# zx7b
+
+.PHONY: local-zx7b
+local-zx7b: $(INSTALLDIR)/zx7b$(EXESUFFIX)
+
+ifeq ($(_DoBuild),1)
+
+$(INSTALLDIR)/zx7b$(EXESUFFIX): zx7b/zx7b$(EXESUFFIX)
+	cp $< $@
+
+zx7b/zx7b$(EXESUFFIX): | zx7b
 	$(MAKE) -w -C $|
 
-../bin/$(BIN2HEX): tools/$(BIN2HEX)
+.PHONY: clean-zx7b
+clean-zx7b: | zx7b
+	$(MAKE) -w -C $| clean
+	rm -f $(INSTALLDIR)/zx7b$(EXESUFFIX)
+
+endif
+
+# tools
+
+INSTALLED_TOOLS:=\
+ $(INSTALLDIR)/bin2hex$(EXESUFFIX)\
+ $(INSTALLDIR)/fcut$(EXESUFFIX)\
+ $(INSTALLDIR)/fpad$(EXESUFFIX)\
+ $(INSTALLDIR)/fpoke$(EXESUFFIX)\
+ $(INSTALLDIR)/GenRom$(EXESUFFIX)\
+ $(INSTALLDIR)/AddItem$(EXESUFFIX)
+
+.PHONY: local-tools
+local-tools: $(INSTALLED_TOOLS)
+
+ifeq ($(_DoBuild),1)
+
+$(INSTALLDIR)/bin2hex$(EXESUFFIX): tools/bin2hex$(EXESUFFIX)
 	cp $< $@
 
-../bin/$(FCUT): tools/$(FCUT)
+$(INSTALLDIR)/fcut$(EXESUFFIX): tools/fcut$(EXESUFFIX)
 	cp $< $@
 
-../bin/$(FPAD): tools/$(FPAD)
+$(INSTALLDIR)/fpad$(EXESUFFIX): tools/fpad$(EXESUFFIX)
 	cp $< $@
 
-../bin/$(FPOKE): tools/$(FPOKE)
+$(INSTALLDIR)/fpoke$(EXESUFFIX): tools/fpoke$(EXESUFFIX)
 	cp $< $@
 
-../bin/$(GENROM): tools/$(GENROM)
+$(INSTALLDIR)/GenRom$(EXESUFFIX): tools/GenRom$(EXESUFFIX)
 	cp $< $@
 
-../bin/$(ADDITEM): tools/$(ADDITEM)
+$(INSTALLDIR)/AddItem$(EXESUFFIX): tools/AddItem$(EXESUFFIX)
 	cp $< $@
 
-tools/$(BIN2HEX) \
-tools/$(FCUT) \
-tools/$(FPAD) \
-tools/$(FPOKE) \
-tools/$(GENROM) \
-tools/$(ADDITEM): | tools
-	$(MAKE) -w -C $|
+tools/%$(EXESUFFIX): | tools
+	$(MAKE) -w -C $| $(@F)
+
+.PHONY: clean-tools
+clean-tools: | tools
+	$(MAKE) -w -C $| clean
+	rm -f $(INSTALLED_TOOLS)
+
 endif
 
 .PHONY: clean
-ifneq ($(_DoClean),1)
-clean:;
+ifeq ($(_DoClean),1)
+clean: clean-sjasmplus clean-z88dk clean-zx7b clean-tools
 else
-clean: | sjasmplus sjasmplus.mk zx7b tools
-	$(MAKE) -w -C sjasmplus -f ../sjasmplus.mk clean
-	$(MAKE) -w -C zx7b clean
-	$(MAKE) -w -C tools clean
-	rm -f $(TOOLS)
+clean: clean-sjasmplus clean-z88dk
+endif
+
+.PHONY: dist-clean
+ifeq ($(_DoClean),1)
+dist-clean: dist-clean-sjasmplus dist-clean-z88dk clean-zx7b clean-tools
+else
+dist-clean: dist-clean-sjasmplus dist-clean-z88dk
 endif
diff --git a/sdk/src/sjasmplus.mk b/sdk/src/sjasmplus.mk
index 35cc03b..0bf51de 100644
--- a/sdk/src/sjasmplus.mk
+++ b/sdk/src/sjasmplus.mk
@@ -17,7 +17,6 @@
 # Notes:
 #   BUILD variable may be set in user's environment.
 
-
 include ../../common.mk
 
 ifeq ($(BUILD),mingw32)
@@ -28,13 +27,11 @@ else
 CMAKEFLAGS	:=
 endif
 
-SJASMPLUS	:= sjasmplus$(EXECEXT)
-
-build/$(SJASMPLUS): | build/Makefile
+build/sjasmplus$(EXESUFFIX): | build/Makefile
 	$(MAKE) -w -C build
 
 build/Makefile: | build
-	cd build && cmake $(CMAKEFLAGS) ..
+	cd $| && cmake $(CMAKEFLAGS) ..
 
 build:
 	mkdir $@
diff --git a/sdk/src/tools/Makefile b/sdk/src/tools/Makefile
index 90a3dd5..100d23f 100644
--- a/sdk/src/tools/Makefile
+++ b/sdk/src/tools/Makefile
@@ -13,49 +13,27 @@
 #
 # where:
 #   <BUILD> is one of: mingw32, mingw64.
-#   <TARGET> is one of values for TOOLS variable (see below).
+#   <TARGET> is one of values for TARGETS variable (see below).
 #
 # Notes:
 #   BUILD variable may be set in user's environment.
 
 include ../../common.mk
 
-BIN2HEX	:= bin2hex$(EXECEXT)
-FCUT	:= fcut$(EXECEXT)
-FPAD	:= fpad$(EXECEXT)
-FPOKE	:= fpoke$(EXECEXT)
-GENROM	:= GenRom$(EXECEXT)
-ADDITEM	:= AddItem$(EXECEXT)
-
-TOOLS:=\
- $(BIN2HEX) \
- $(FCUT) \
- $(FPAD) \
- $(FPOKE) \
- $(GENROM) \
- $(ADDITEM)
+TARGETS:=\
+ bin2hex$(EXESUFFIX)\
+ fcut$(EXESUFFIX)\
+ fpad$(EXESUFFIX)\
+ fpoke$(EXESUFFIX)\
+ GenRom$(EXESUFFIX)\
+ AddItem$(EXESUFFIX)
 
 .PHONY: all
-all: $(TOOLS)
+all: $(TARGETS)
 
-$(BIN2HEX): bin2hex.c
-	$(CC) $(CFLAGS) -o $@ $<
-
-$(FCUT): fcut.c
-	$(CC) $(CFLAGS) -o $@ $<
-
-$(FPAD): fpad.c
-	$(CC) $(CFLAGS) -o $@ $<
-
-$(FPOKE): fpoke.c
-	$(CC) $(CFLAGS) -o $@ $<
-
-$(GENROM): GenRom.c
-	$(CC) $(CFLAGS) -o $@ $<
-
-$(ADDITEM): AddItem.c
+%$(EXESUFFIX): %.c Makefile
 	$(CC) $(CFLAGS) -o $@ $<
 
 .PHONY: clean
 clean:
-	rm -f $(TOOLS)
+	rm -f $(TARGETS)
diff --git a/sdk/src/z88dk.mk b/sdk/src/z88dk.mk
new file mode 100644
index 0000000..96371c9
--- /dev/null
+++ b/sdk/src/z88dk.mk
@@ -0,0 +1,30 @@
+# SPDX-FileCopyrightText: 2021 Ivan Tatarinov <ivan-tat@ya.ru>
+#
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# Supported environments:
+#   * GNU on Linux, FreeBSD etc.
+#   * GNU on Windows NT (using MinGW/MSYS/Cygwin/WSL)
+#
+# Build:
+#   make [BUILD=<BUILD>] -w -C z88dk -f ../z88dk.mk
+# Clean:
+#   make [BUILD=<BUILD>] -w -C z88dk -f ../z88dk.mk clean
+#
+# where:
+#   <BUILD> is one of: mingw32, mingw64.
+#
+# Notes:
+#   BUILD variable may be set in user's environment.
+
+include ../../common.mk
+
+.PHONY: all
+all: | build.sh
+	chmod 777 $|
+	./build.sh
+
+.PHONY: clean
+clean: | build.sh
+	chmod 777 $|
+	./build.sh -C
diff --git a/sdk/src/z88dk.patch b/sdk/src/z88dk.patch
new file mode 100644
index 0000000..3047bf0
--- /dev/null
+++ b/sdk/src/z88dk.patch
@@ -0,0 +1,18 @@
+--- z88dk/build.sh	2021-04-20 00:03:23.742154100 +0300
++++ z88dk/build_Cygwin.sh	2021-04-20 00:04:56.836048400 +0300
+@@ -48,6 +48,7 @@
+ builddir=`pwd $0`
+ ZCCCFG=$builddir/lib/config
+ PATH=$builddir/bin:$PATH
++if test x$OS = xWindows_NT -a x$OSTYPE = xcygwin; then ZCCCFG=`cygpath -m $ZCCCFG`; fi
+ export ZCCCFG
+ export PATH
+ 
+@@ -143,6 +144,7 @@
+ 
+ ZCCCFG=`pwd`/lib/config/                # Set ZCCCFG to the lib config directory
+ mkdir -p $ZCCCFG                        # Guarantee that the directory exists
++if test x$OS = xWindows_NT -a x$OSTYPE = xcygwin; then ZCCCFG=`cygpath -m $ZCCCFG`; fi
+ export ZCCCFG
+ 
+ 
diff --git a/sdk/src/zx7b/Makefile b/sdk/src/zx7b/Makefile
index 04ece1f..c2b9b28 100644
--- a/sdk/src/zx7b/Makefile
+++ b/sdk/src/zx7b/Makefile
@@ -13,20 +13,21 @@
 #
 # where:
 #   <BUILD> is one of: mingw32, mingw64.
-#   <TARGET> is one of values of TOOLS variable (see below).
+#   <TARGET> is the value of TARGET variable (see below).
 #
 # Notes:
 #   BUILD variable may be set in user's environment.
 
 include ../../common.mk
 
-ZX7B	:= zx7b$(EXECEXT)
+TARGET	:= zx7b$(EXESUFFIX)
 
-$(ZX7B): zx7b.c
+.PHONY: all
+all: $(TARGET)
+
+%$(EXESUFFIX): %.c Makefile
 	$(CC) $(CFLAGS) -o $@ $<
 
-zx7b.c:
-	wget -c https://github.com/antoniovillena/zx7b/raw/master/zx7b.c
-
+.PHONY: clean
 clean:
-	rm -f $(ZX7B)
+	rm -f $(TARGET)