diff --git a/.gitignore b/.gitignore
index 718307f8..b9ac472f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -31,3 +31,5 @@ tmp.db-lck
 valgrind.*
 src/elements/version.c
 src/elements/config.h
+dist/
+*.tar*
diff --git a/GNUmakefile b/GNUmakefile
index bcf56c37..2a2f5938 100644
--- a/GNUmakefile
+++ b/GNUmakefile
@@ -8,90 +8,55 @@
 # in README and source code if you do. There may be other macros of interest.
 
 # install sandbox
-SANDBOX	?=
+SANDBOX ?=
 
 # install prefixes (inside sandbox)
-prefix	?= /usr/local
-mandir	?= $(prefix)/man
+prefix  ?= /usr/local
+mandir  ?= $(prefix)/man
 
 # lib/bin suffix for multiarch/biarch, e.g. '.x86_64'
-suffix	?=
-
-CC	?= gcc
-CXX	?= g++
-LD	?= ld
-MDBX_OPTIONS ?= -D_GNU_SOURCE=1 -DNDEBUG=1 -DLIBMDBX_EXPORTS=1
-CFLAGS	?= -O2 -g3 -Wall -Werror -Wextra -ffunction-sections -fPIC -fvisibility=hidden -std=gnu11 -pthread
+suffix  ?=
 
+CC      ?= gcc
+CXX     ?= g++
+LD      ?= ld
+MDBX_OPTIONS ?= -D_GNU_SOURCE=1 -DNDEBUG=1
+CFLAGS  ?= -O2 -g3 -Wall -Werror -Wextra -ffunction-sections -fPIC -fvisibility=hidden -std=gnu11 -pthread
 CXXFLAGS = -std=c++11 $(filter-out -std=gnu11,$(CFLAGS))
-TESTDB	?= $(shell [ -d /dev/shm ] && echo /dev/shm || echo /tmp)/mdbx-test.db
-TESTLOG ?= $(shell [ -d /dev/shm ] && echo /dev/shm || echo /tmp)/mdbx-test.log
 
 # LY: '--no-as-needed,-lrt' for ability to built with modern glibc, but then run with the old
-LDFLAGS	?= $(shell $(LD) --help 2>/dev/null | grep -q -- --gc-sections && echo '-Wl,--gc-sections,-z,relro,-O1')$(shell $(LD) --help 2>/dev/null | grep -q -- -dead_strip && echo '-Wl,-dead_strip')
+LDFLAGS ?= $(shell $(LD) --help 2>/dev/null | grep -q -- --gc-sections && echo '-Wl,--gc-sections,-z,relro,-O1')$(shell $(LD) --help 2>/dev/null | grep -q -- -dead_strip && echo '-Wl,-dead_strip')
 EXE_LDFLAGS ?= -pthread
 
-# LY: just for benchmarking
-IOARENA ?= $(shell \
-  (test -x ../ioarena/@BUILD/src/ioarena && echo ../ioarena/@BUILD/src/ioarena) || \
-  (test -x ../../@BUILD/src/ioarena && echo ../../@BUILD/src/ioarena) || \
-  (test -x ../../src/ioarena && echo ../../src/ioarena) || which ioarena)
-NN	?= 25000000
+################################################################################
 
-########################################################################
+UNAME      := $(shell uname -s 2>/dev/null || echo Unknown)
+define uname2sosuffix
+  case "$(UNAME)" in
+    Darwin*|Mach*) echo dylib;;
+    CYGWIN*|MINGW*|MSYS*|Windows*) echo dll;;
+    *) echo so;;
+  esac
+endef
+SO_SUFFIX  := $(shell $(uname2sosuffix))
 
-ifdef MSVC
-  UNAME := Windows
-  TEST_OSAL := windows
-  TEST_ITER := 42
-else
-  UNAME	:= $(shell uname -s 2>/dev/null || echo Unknown)
-  define uname2osal
-    case "$(UNAME)" in
-      CYGWIN*|MINGW*|MSYS*|Windows*) echo windows;;
-      *) echo unix;;
-    esac
-  endef
-  define uname2titer
-    case "$(UNAME)" in
-      Darwin*|Mach*) echo 3;;
-      *) echo 42;;
-    esac
-  endef
-  define uname2suffix
-    case "$(UNAME)" in
-      Darwin*|Mach*) echo dylib;;
-      CYGWIN*|MINGW*|MSYS*|Windows*) echo dll;;
-      *) echo so;;
-    esac
-  endef
-  TEST_OSAL := $(shell $(uname2osal))
-  TEST_ITER := $(shell $(uname2titer))
-  SO_SUFFIX := $(shell $(uname2suffix))
-endif
-
-HEADERS		:= mdbx.h
-LIBRARIES	:= libmdbx.a libmdbx.$(SO_SUFFIX)
-TOOLS		:= mdbx_stat mdbx_copy mdbx_dump mdbx_load mdbx_chk
-MANPAGES	:= mdbx_stat.1 mdbx_copy.1 mdbx_dump.1 mdbx_load.1
-SHELL		:= /bin/bash
-
-ALLOY_DEPS      := $(wildcard src/elements/*)
-TEST_SRC	:= test/osal-$(TEST_OSAL).cc $(filter-out $(wildcard test/osal-*.cc), $(wildcard test/*.cc))
-TEST_INC	:= $(wildcard test/*.h)
-TEST_OBJ	:= $(patsubst %.cc,%.o,$(TEST_SRC))
+HEADERS    := mdbx.h
+LIBRARIES  := libmdbx.a libmdbx.$(SO_SUFFIX)
+TOOLS      := mdbx_stat mdbx_copy mdbx_dump mdbx_load mdbx_chk
+MANPAGES   := mdbx_stat.1 mdbx_copy.1 mdbx_dump.1 mdbx_load.1
+SHELL      := /bin/bash
 
 .PHONY: mdbx all install clean check coverage
 
-all: $(LIBRARIES) $(TOOLS) mdbx_test example
+all: $(LIBRARIES) $(TOOLS)
 
 mdbx: libmdbx.a libmdbx.$(SO_SUFFIX)
 
-example: mdbx.h tutorial/sample-mdbx.c libmdbx.$(SO_SUFFIX)
-	$(CC) $(CFLAGS) -I. tutorial/sample-mdbx.c ./libmdbx.$(SO_SUFFIX) -o example
-
 tools: $(TOOLS)
 
+strip: all
+	strip libmdbx.$(SO_SUFFIX) $(TOOLS)
+
 install: $(LIBRARIES) $(TOOLS) $(HEADERS)
 	mkdir -p $(SANDBOX)$(prefix)/bin$(suffix) \
 		&& cp -t $(SANDBOX)$(prefix)/bin$(suffix) $(TOOLS) && \
@@ -105,22 +70,97 @@ install: $(LIBRARIES) $(TOOLS) $(HEADERS)
 clean:
 	rm -rf $(TOOLS) mdbx_test @* *.[ao] *.[ls]o *~ tmp.db/* *.gcov *.log *.err src/*.o test/*.o
 
-check:	all
+libmdbx.a: mdbx-static.o
+	$(AR) rs $@ $?
+
+libmdbx.$(SO_SUFFIX): mdbx-dylib.o
+	$(CC) $(CFLAGS) $^ -pthread -shared $(LDFLAGS) -o $@
+
+#> dist-cutoff-begin
+ifeq ($(wildcard mdbx.c),mdbx.c)
+#< dist-cutoff-end
+
+################################################################################
+# Amalgamated source code, i.e. distributed after `make dists`
+
+mdbx-config.h: mdbx-config.h.in mdbx.c $(lastword $(MAKEFILE_LIST))
+	(echo '#define MDBX_BUILD_TIMESTAMP "$(shell date +%Y-%m-%dT%H:%M:%S%z)"' \
+	&& echo '#define MDBX_BUILD_OPTIONS_STRING "$(MDBX_OPTIONS)"' \
+	&& echo '#define MDBX_BUILD_FLAGS "$(CFLAGS) $(LDFLAGS)"' \
+	&& echo '#define MDBX_BUILD_COMPILER "$(shell set -o pipefail; $(CC) --version | head -1 || echo 'Please use GCC or CLANG compatible compiler')"' \
+	&& echo '#define MDBX_BUILD_TARGET "$(shell set -o pipefail; LC_ALL=C $(CC) -v 2>&1 | grep -i '^Target:' | cut -d ' ' -f 2- || echo 'Please use GCC or CLANG compatible compiler')"' \
+	) > $@ || rm -f $@
+
+mdbx-dylib.o: mdbx-config.h mdbx.c $(lastword $(MAKEFILE_LIST))
+	$(CC) $(CFLAGS) $(MDBX_OPTIONS) -DLIBMDBX_EXPORTS=1 -c mdbx.c -o $@
+
+mdbx-static.o: mdbx-config.h mdbx.c $(lastword $(MAKEFILE_LIST))
+	$(CC) $(CFLAGS) $(MDBX_OPTIONS) -ULIBMDBX_EXPORTS -c mdbx.c -o $@
+
+mdbx_%:	mdbx_%.c libmdbx.a
+	$(CC) $(CFLAGS) $(MDBX_OPTIONS) $^ $(EXE_LDFLAGS) -o $@
+
+#> dist-cutoff-begin
+else
+################################################################################
+# Plain (non-amalgamated) sources
+
+define uname2osal
+  case "$(UNAME)" in
+    CYGWIN*|MINGW*|MSYS*|Windows*) echo windows;;
+    *) echo unix;;
+  esac
+endef
+define uname2titer
+  case "$(UNAME)" in
+    Darwin*|Mach*) echo 3;;
+    *) echo 12;;
+  esac
+endef
+TEST_OSAL  := $(shell $(uname2osal))
+TEST_ITER  := $(shell $(uname2titer))
+TESTDB     ?= $(shell [ -d /dev/shm ] && echo /dev/shm || echo /tmp)/mdbx-test.db
+TESTLOG    ?= $(shell [ -d /dev/shm ] && echo /dev/shm || echo /tmp)/mdbx-test.log
+TEST_SRC   := test/osal-$(TEST_OSAL).cc $(filter-out $(wildcard test/osal-*.cc), $(wildcard test/*.cc))
+TEST_INC   := $(wildcard test/*.h)
+TEST_OBJ   := $(patsubst %.cc,%.o,$(TEST_SRC))
+
+check: all example mdbx_test
 	rm -f $(TESTDB) $(TESTLOG) && (set -o pipefail; ./mdbx_test --repeat=$(TEST_ITER) --pathname=$(TESTDB) --dont-cleanup-after basic | tee -a $(TESTLOG) | tail -n 42) \
 	&& ./mdbx_chk -vvn $(TESTDB) && ./mdbx_chk -vvn $(TESTDB)-copy
 
-check-singleprocess:	all
+example: mdbx.h tutorial/sample-mdbx.c libmdbx.$(SO_SUFFIX)
+	$(CC) $(CFLAGS) -I. tutorial/sample-mdbx.c ./libmdbx.$(SO_SUFFIX) -o example
+
+check-singleprocess: all
 	rm -f $(TESTDB) $(TESTLOG) && (set -o pipefail; \
 		./mdbx_test --repeat=4 --pathname=$(TESTDB) --dont-cleanup-after --hill && \
 		./mdbx_test --repeat=2 --pathname=$(TESTDB) --dont-cleanup-before --dont-cleanup-after --copy \
 		| tee -a $(TESTLOG) | tail -n 42) \
 	&& ./mdbx_chk -vvn $(TESTDB) && ./mdbx_chk -vvn $(TESTDB)-copy
 
-check-fault:	all
+check-fault: all
 	rm -f $(TESTDB) $(TESTLOG) && (set -o pipefail; ./mdbx_test --pathname=$(TESTDB) --inject-writefault=42 --dump-config --dont-cleanup-after basic | tee -a $(TESTLOG) | tail -n 42) \
 	; ./mdbx_chk -vvnw $(TESTDB) && ([ ! -e $(TESTDB)-copy ] || ./mdbx_chk -vvn $(TESTDB)-copy)
 
+define test-rule
+$(patsubst %.cc,%.o,$(1)): $(1) $(TEST_INC) mdbx.h $(lastword $(MAKEFILE_LIST))
+	$(CXX) $(CXXFLAGS) $(MDBX_OPTIONS) -c $(1) -o $$@
+
+endef
+$(foreach file,$(TEST_SRC),$(eval $(call test-rule,$(file))))
+
+mdbx_%:	src/tools/mdbx_%.c libmdbx.a
+	$(CC) $(CFLAGS) $(MDBX_OPTIONS) $^ $(EXE_LDFLAGS) -o $@
+
+mdbx_test: $(TEST_OBJ) libmdbx.$(SO_SUFFIX)
+	$(CXX) $(CXXFLAGS) $(TEST_OBJ) -Wl,-rpath . -L . -l mdbx $(EXE_LDFLAGS) -o $@
+
+ALLOY_DEPS = $(wildcard src/elements/*)
 MDBX_VERSION_GIT = ${shell set -o pipefail; git describe --tags | sed -n 's|^v*\([0-9]\{1,\}\.[0-9]\{1,\}\.[0-9]\{1,\}\)\(.*\)|\1|p' || echo 'Please fetch tags and/or install latest git version'}
+MDBX_VERSION_SUFFIX = $(shell set -o pipefail; git describe --tags --long --dirty=-dirty | tr -c -s '[a-zA-Z0-9]\n' _ || echo 'Please fetch tags and/or install latest git version')
+MDBX_BUILD_SOURCERY = $(shell set -o pipefail; $(MAKE) -s src/elements/version.c && (openssl dgst -r -sha256 src/elements/version.c || sha256sum src/elements/version.c || shasum -a 256 src/elements/version.c) 2>/dev/null | cut -d ' ' -f 1 || echo 'Please install openssl or sha256sum or shasum')_$(MDBX_VERSION_SUFFIX)
+
 src/elements/version.c: src/elements/version.c.in $(lastword $(MAKEFILE_LIST)) .git/HEAD .git/index .git/refs/tags
 	sed \
 		-e "s|@MDBX_GIT_TIMESTAMP@|$(shell git show --no-patch --format=%cI HEAD || echo 'Please install latest get version')|" \
@@ -139,32 +179,114 @@ src/elements/config.h: src/elements/version.c $(lastword $(MAKEFILE_LIST))
 	&& echo '#define MDBX_BUILD_FLAGS "$(CFLAGS) $(LDFLAGS)"' \
 	&& echo '#define MDBX_BUILD_COMPILER "$(shell set -o pipefail; $(CC) --version | head -1 || echo 'Please use GCC or CLANG compatible compiler')"' \
 	&& echo '#define MDBX_BUILD_TARGET "$(shell set -o pipefail; LC_ALL=C $(CC) -v 2>&1 | grep -i '^Target:' | cut -d ' ' -f 2- || echo 'Please use GCC or CLANG compatible compiler')"' \
-	&& echo '#define MDBX_BUILD_SOURCERY $(shell set -o pipefail; ((openssl dgst -r -sha256 src/elements/version.c.in || sha256sum src/elements/version.c || shasum -a 256 src/elements/version.c) 2>/dev/null | cut -d ' ' -f 1 && echo -n `git describe --tags --long --dirty=-dirty`) | tr -c -s '[a-zA-Z0-9]' _ || echo 'Please install openssl or sha256sum or shasum')' \
+	&& echo '#define MDBX_BUILD_SOURCERY $(MDBX_BUILD_SOURCERY)' \
 	) > $@ || rm -f $@
 
-libmdbx.o: src/elements/config.h src/elements/version.c src/alloy.c $(ALLOY_DEPS) $(lastword $(MAKEFILE_LIST))
-	$(CC) $(CFLAGS) $(MDBX_OPTIONS) -c src/alloy.c -o $@
+mdbx-dylib.o: src/elements/config.h src/elements/version.c src/alloy.c $(ALLOY_DEPS) $(lastword $(MAKEFILE_LIST))
+	$(CC) $(CFLAGS) $(MDBX_OPTIONS) -DLIBMDBX_EXPORTS=1 -c src/alloy.c -o $@
 
-define test-rule
-$(patsubst %.cc,%.o,$(1)): $(1) $(TEST_INC) mdbx.h $(lastword $(MAKEFILE_LIST))
-	$(CXX) $(CXXFLAGS) $(MDBX_OPTIONS) -c $(1) -o $$@
+mdbx-static.o: src/elements/config.h src/elements/version.c src/alloy.c $(ALLOY_DEPS) $(lastword $(MAKEFILE_LIST))
+	$(CC) $(CFLAGS) $(MDBX_OPTIONS) -ULIBMDBX_EXPORTS -c src/alloy.c -o $@
+
+.PHONY: dist
+dist: lidmbx-sources-$(MDBX_VERSION_SUFFIX).tar.gz $(lastword $(MAKEFILE_LIST))
+
+lidmbx-sources-$(MDBX_VERSION_SUFFIX).tar.gz: dist/mdbx.c dist/mdbx-config.h.in dist/mdbx.h \
+		dist/mdbx_chk.c dist/mdbx_copy.c dist/mdbx_dump.c dist/mdbx_load.c dist/mdbx_stat.c \
+		dist/GNUmakefile $(lastword $(MAKEFILE_LIST))
+	tar -c -a -f $@ --owner=0 --group=0 -C dist mdbx.c mdbx-config.h.in mdbx.h \
+    mdbx_chk.c mdbx_copy.c mdbx_dump.c mdbx_load.c mdbx_stat.c GNUmakefile \
+    && rm dist/@tmp-shared_internals.inc
+
+dist/mdbx.h: mdbx.h src/elements/version.c $(lastword $(MAKEFILE_LIST))
+	mkdir -p dist && cp $< $@
+
+dist/GNUmakefile: GNUmakefile
+	mkdir -p dist && sed -e '/^#> dist-cutoff-begin/,/^#< dist-cutoff-end/d' $< > $@
+
+dist/@tmp-shared_internals.inc: src/elements/version.c $(ALLOY_DEPS) $(lastword $(MAKEFILE_LIST))
+	mkdir -p dist && sed \
+		-e 's|#include "config.h"|@INCLUDE "mdbx-config.h"\n#define MDBX_ALLOY 1\n#define MDBX_BUILD_SOURCERY $(MDBX_BUILD_SOURCERY)|' \
+		-e 's|#include "../../mdbx.h"|@INCLUDE "mdbx.h"|' \
+		-e '/#include "defs.h"/r src/elements/defs.h' \
+		-e '/#include "osal.h"/r src/elements/osal.h' \
+		src/elements/internals.h > $@
+
+dist/mdbx.c: dist/@tmp-shared_internals.inc $(lastword $(MAKEFILE_LIST))
+	mkdir -p dist && (cat dist/@tmp-shared_internals.inc \
+	&& cat src/elements/core.c src/elements/osal.c src/elements/version.c \
+	&& echo '#if defined(_WIN32) || defined(_WIN64)' \
+	&& cat src/elements/lck-windows.c && echo '#else /* LCK-implementation */' \
+	&& cat src/elements/lck-posix.c && echo '#endif /* LCK-implementation */' \
+	) | grep -v -e '#include "' -e '#pragma once' | sed 's|@INCLUDE|#include|' > $@
+
+define dist-tool-rule
+dist/mdbx_$(1).c: src/tools/mdbx_$(1).c src/tools/wingetopt.h src/tools/wingetopt.c dist/mdbx.c $(lastword $(MAKEFILE_LIST))
+	mkdir -p dist && sed \
+		-e '/#include "..\/elements\/internals.h"/r dist/@tmp-shared_internals.inc' \
+		-e '/#include "wingetopt.h"/r r/src/tools/wingetopt.c' \
+		-e '/#include "wingetopt.h"/r r/src/tools/wingetopt.h' \
+		src/tools/mdbx_$(1).c \
+	| grep -v -e '#include "' -e '#pragma once' -e '#define MDBX_ALLOY' \
+	| sed 's|@INCLUDE|#include|' > $$@
 
 endef
-$(foreach file,$(TEST_SRC),$(eval $(call test-rule,$(file))))
+$(foreach file,chk copy dump load stat,$(eval $(call dist-tool-rule,$(file))))
 
-libmdbx.a: libmdbx.o
-	$(AR) rs $@ $?
+dist/mdbx-config.h.in: src/elements/config.h.in $(lastword $(MAKEFILE_LIST))
+	mkdir -p dist && grep -v MDBX_BUILD_SOURCERY $< > $@
 
-libmdbx.$(SO_SUFFIX): libmdbx.o
-	$(CC) $(CFLAGS) $^ -pthread -shared $(LDFLAGS) -o $@
+endif
 
-mdbx_%:	src/tools/mdbx_%.c libmdbx.a
-	$(CC) $(CFLAGS) $(MDBX_OPTIONS) $^ $(EXE_LDFLAGS) -o $@
+################################################################################
+# Cross-compilation simple test
 
-mdbx_test: $(TEST_OBJ) libmdbx.$(SO_SUFFIX)
-	$(CXX) $(CXXFLAGS) $(TEST_OBJ) -Wl,-rpath . -L . -l mdbx $(EXE_LDFLAGS) -o $@
+CROSS_LIST = mips-linux-gnu-gcc \
+	powerpc64-linux-gnu-gcc powerpc-linux-gnu-gcc \
+	arm-linux-gnueabihf-gcc aarch64-linux-gnu-gcc
 
-###############################################################################
+# hppa-linux-gnu-gcc          - don't supported by current qemu release
+# s390x-linux-gnu-gcc         - qemu troubles (hang/abort)
+# sh4-linux-gnu-gcc           - qemu troubles (pread syscall, etc)
+# mips64-linux-gnuabi64-gcc   - qemu troubles (pread syscall, etc)
+# sparc64-linux-gnu-gcc       - qemu troubles (fcntl for F_SETLK/F_GETLK)
+# alpha-linux-gnu-gcc         - qemu (or gcc) troubles (coredump)
+
+CROSS_LIST_NOQEMU = hppa-linux-gnu-gcc s390x-linux-gnu-gcc \
+	sh4-linux-gnu-gcc mips64-linux-gnuabi64-gcc \
+	sparc64-linux-gnu-gcc alpha-linux-gnu-gcc
+
+cross-gcc:
+	@echo "CORRESPONDING CROSS-COMPILERs ARE REQUIRED."
+	@echo "FOR INSTANCE: apt install g++-aarch64-linux-gnu g++-alpha-linux-gnu g++-arm-linux-gnueabihf g++-hppa-linux-gnu g++-mips-linux-gnu g++-mips64-linux-gnuabi64 g++-powerpc-linux-gnu g++-powerpc64-linux-gnu g++-s390x-linux-gnu g++-sh4-linux-gnu g++-sparc64-linux-gnu"
+	@for CC in $(CROSS_LIST_NOQEMU) $(CROSS_LIST); do \
+		echo "===================== $$CC"; \
+		$(MAKE) clean && CC=$$CC CXX=$$(echo $$CC | sed 's/-gcc/-g++/') EXE_LDFLAGS=-static $(MAKE) all || exit $$?; \
+	done
+
+# Unfortunately qemu don't provide robust support for futexes.
+# Therefore it is impossible to run full multi-process tests.
+cross-qemu:
+	@echo "CORRESPONDING CROSS-COMPILERs AND QEMUs ARE REQUIRED."
+	@echo "FOR INSTANCE: "
+	@echo "	1) apt install g++-aarch64-linux-gnu g++-alpha-linux-gnu g++-arm-linux-gnueabihf g++-hppa-linux-gnu g++-mips-linux-gnu g++-mips64-linux-gnuabi64 g++-powerpc-linux-gnu g++-powerpc64-linux-gnu g++-s390x-linux-gnu g++-sh4-linux-gnu g++-sparc64-linux-gnu"
+	@echo "	2) apt install binfmt-support qemu-user-static qemu-user qemu-system-arm qemu-system-mips qemu-system-misc qemu-system-ppc qemu-system-sparc"
+	@for CC in $(CROSS_LIST); do \
+		echo "===================== $$CC + qemu"; \
+		$(MAKE) clean && \
+			CC=$$CC CXX=$$(echo $$CC | sed 's/-gcc/-g++/') EXE_LDFLAGS=-static XCFLAGS="-DMDBX_SAFE4QEMU $(XCFLAGS)" \
+			$(MAKE) check-singleprocess || exit $$?; \
+	done
+
+#< dist-cutoff-end
+################################################################################
+# Benchmarking by ioarena
+
+IOARENA ?= $(shell \
+  (test -x ../ioarena/@BUILD/src/ioarena && echo ../ioarena/@BUILD/src/ioarena) || \
+  (test -x ../../@BUILD/src/ioarena && echo ../../@BUILD/src/ioarena) || \
+  (test -x ../../src/ioarena && echo ../../src/ioarena) || which ioarena)
+NN	?= 25000000
 
 ifneq ($(wildcard $(IOARENA)),)
 
@@ -212,61 +334,3 @@ bench-debug: bench-debug_10.txt
 bench-quartet: bench-mdbx_$(NN).txt bench-lmdb_$(NN).txt bench-rocksdb_$(NN).txt bench-wiredtiger_$(NN).txt
 
 endif
-
-###############################################################################
-
-ci-rule = ( CC=$$(which $1); if [ -n "$$CC" ]; then \
-		echo -n "probe by $2 ($$(readlink -f $$(which $$CC))): " && \
-		$(MAKE) clean >$1.log 2>$1.err && \
-		$(MAKE) CC=$$(readlink -f $$CC) XCFLAGS="-UNDEBUG -DMDBX_DEBUG=2 -DLIBMDBX_EXPORTS=1" check 1>$1.log 2>$1.err && echo "OK" \
-			|| ( echo "FAILED"; cat $1.err >&2; exit 1 ); \
-	else echo "no $2 ($1) for probe"; fi; )
-ci:
-	@if [ "$$(readlink -f $$(which $(CC)))" != "$$(readlink -f $$(which gcc || echo /bin/false))" -a \
-		"$$(readlink -f $$(which $(CC)))" != "$$(readlink -f $$(which clang || echo /bin/false))" -a \
-		"$$(readlink -f $$(which $(CC)))" != "$$(readlink -f $$(which icc || echo /bin/false))" ]; then \
-		$(call ci-rule,$(CC),default C compiler); \
-	fi
-	@$(call ci-rule,gcc,GCC)
-	@$(call ci-rule,clang,clang LLVM)
-	@$(call ci-rule,icc,Intel C)
-
-###############################################################################
-
-CROSS_LIST = mips-linux-gnu-gcc \
-	powerpc64-linux-gnu-gcc powerpc-linux-gnu-gcc \
-	arm-linux-gnueabihf-gcc aarch64-linux-gnu-gcc
-
-# hppa-linux-gnu-gcc		- don't supported by current qemu release
-# s390x-linux-gnu-gcc		- qemu troubles (hang/abort)
-# sh4-linux-gnu-gcc		- qemu troubles (pread syscall, etc)
-# mips64-linux-gnuabi64-gcc	- qemu troubles (pread syscall, etc)
-# sparc64-linux-gnu-gcc		- qemu troubles (fcntl for F_SETLK/F_GETLK)
-# alpha-linux-gnu-gcc		- qemu (or gcc) troubles (coredump)
-
-CROSS_LIST_NOQEMU = hppa-linux-gnu-gcc s390x-linux-gnu-gcc \
-	sh4-linux-gnu-gcc mips64-linux-gnuabi64-gcc \
-	sparc64-linux-gnu-gcc alpha-linux-gnu-gcc
-
-cross-gcc:
-	@echo "CORRESPONDING CROSS-COMPILERs ARE REQUIRED."
-	@echo "FOR INSTANCE: apt install g++-aarch64-linux-gnu g++-alpha-linux-gnu g++-arm-linux-gnueabihf g++-hppa-linux-gnu g++-mips-linux-gnu g++-mips64-linux-gnuabi64 g++-powerpc-linux-gnu g++-powerpc64-linux-gnu g++-s390x-linux-gnu g++-sh4-linux-gnu g++-sparc64-linux-gnu"
-	@for CC in $(CROSS_LIST_NOQEMU) $(CROSS_LIST); do \
-		echo "===================== $$CC"; \
-		$(MAKE) clean && CC=$$CC CXX=$$(echo $$CC | sed 's/-gcc/-g++/') EXE_LDFLAGS=-static $(MAKE) all || exit $$?; \
-	done
-
-#
-# Unfortunately qemu don't provide robust support for futexes.
-# Therefore it is impossible to run full multi-process tests.
-cross-qemu:
-	@echo "CORRESPONDING CROSS-COMPILERs AND QEMUs ARE REQUIRED."
-	@echo "FOR INSTANCE: "
-	@echo "	1) apt install g++-aarch64-linux-gnu g++-alpha-linux-gnu g++-arm-linux-gnueabihf g++-hppa-linux-gnu g++-mips-linux-gnu g++-mips64-linux-gnuabi64 g++-powerpc-linux-gnu g++-powerpc64-linux-gnu g++-s390x-linux-gnu g++-sh4-linux-gnu g++-sparc64-linux-gnu"
-	@echo "	2) apt install binfmt-support qemu-user-static qemu-user qemu-system-arm qemu-system-mips qemu-system-misc qemu-system-ppc qemu-system-sparc"
-	@for CC in $(CROSS_LIST); do \
-		echo "===================== $$CC + qemu"; \
-		$(MAKE) clean && \
-			CC=$$CC CXX=$$(echo $$CC | sed 's/-gcc/-g++/') EXE_LDFLAGS=-static XCFLAGS="-DMDBX_SAFE4QEMU $(XCFLAGS)" \
-			$(MAKE) check-singleprocess || exit $$?; \
-	done
diff --git a/mdbx.h b/mdbx.h
index 34cdbed0..3ffdd767 100644
--- a/mdbx.h
+++ b/mdbx.h
@@ -187,12 +187,14 @@ typedef pthread_t mdbx_tid_t;
 #define MDBX_VERSION_MAJOR 0
 #define MDBX_VERSION_MINOR 3
 
+#ifndef LIBMDBX_API
 #if defined(LIBMDBX_EXPORTS)
 #define LIBMDBX_API __dll_export
 #elif defined(LIBMDBX_IMPORTS)
 #define LIBMDBX_API __dll_import
 #else
 #define LIBMDBX_API
+#endif
 #endif /* LIBMDBX_API */
 
 #ifdef __cplusplus
diff --git a/src/elements/core.c b/src/elements/core.c
index c30b23e0..1d7011b8 100644
--- a/src/elements/core.c
+++ b/src/elements/core.c
@@ -35,7 +35,7 @@
  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
 
-#include "./internals.h"
+#include "internals.h"
 
 /*----------------------------------------------------------------------------*/
 /* Internal inlines */
diff --git a/src/elements/internals.h b/src/elements/internals.h
index a96bb0a6..41daaba4 100644
--- a/src/elements/internals.h
+++ b/src/elements/internals.h
@@ -85,7 +85,7 @@
 #endif                          /* _MSC_VER (warnings) */
 
 #include "../../mdbx.h"
-#include "./defs.h"
+#include "defs.h"
 
 #if defined(__GNUC__) && !__GNUC_PREREQ(4,2)
     /* Actualy libmdbx was not tested with compilers older than GCC from RHEL6.
@@ -140,7 +140,7 @@
 #   endif
 #endif /* -Walignment-reduction-ignored */
 
-#include "./osal.h"
+#include "osal.h"
 
 /* *INDENT-ON* */
 /* clang-format on */
diff --git a/src/elements/lck-posix.c b/src/elements/lck-posix.c
index 95c7759a..c317d00e 100644
--- a/src/elements/lck-posix.c
+++ b/src/elements/lck-posix.c
@@ -12,7 +12,7 @@
  * <http://www.OpenLDAP.org/license.html>.
  */
 
-#include "./internals.h"
+#include "internals.h"
 
 /*----------------------------------------------------------------------------*/
 /* global constructor/destructor */
diff --git a/src/elements/lck-windows.c b/src/elements/lck-windows.c
index feef62fc..9f05bc23 100644
--- a/src/elements/lck-windows.c
+++ b/src/elements/lck-windows.c
@@ -12,7 +12,7 @@
  * <http://www.OpenLDAP.org/license.html>.
  */
 
-#include "./internals.h"
+#include "internals.h"
 
 /* PREAMBLE FOR WINDOWS:
  *
diff --git a/src/elements/osal.c b/src/elements/osal.c
index 1bbf69d2..8c19d75a 100644
--- a/src/elements/osal.c
+++ b/src/elements/osal.c
@@ -14,7 +14,7 @@
  * <http://www.OpenLDAP.org/license.html>.
  */
 
-#include "./internals.h"
+#include "internals.h"
 
 #if defined(_WIN32) || defined(_WIN64)