diff --git a/CMakeLists.txt b/CMakeLists.txt
index d990e11..8c47574 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -2,6 +2,11 @@ cmake_minimum_required(VERSION 3.10)
 
 project(tzdb2nx VERSION 1.0)
 
+set(TZDB_VERSION "$ENV{TZDB_VERSION}")
+if ("${TZDB_VERSION}" STREQUAL "")
+    set(TZDB_VERSION "2022c")
+endif()
+
 set(CMAKE_CXX_STANDARD 20)
 
 add_subdirectory(src)
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index dcfc32f..99e953e 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -8,3 +8,4 @@ add_compile_options(
 include_directories(.)
 
 add_subdirectory(tzdb2nx)
+add_subdirectory(tzdb)
diff --git a/src/tzdb/CMakeLists.txt b/src/tzdb/CMakeLists.txt
new file mode 100644
index 0000000..4821cce
--- /dev/null
+++ b/src/tzdb/CMakeLists.txt
@@ -0,0 +1,65 @@
+find_program(GNU_MAKE make)
+if ("${GNU_MAKE}" STREQUAL "GNU_MAKE-NOTFOUND")
+    message(ERROR "make program not found")
+endif()
+
+set(TZDB_ARCHIVE "tzdb-${TZDB_VERSION}.tar.lz")
+set(TZDB_LOCATION "${CMAKE_CURRENT_BINARY_DIR}/tzdb-${TZDB_VERSION}")
+if (NOT (EXISTS "${CMAKE_CURRENT_BINARY_DIR}/${TZDB_ARCHIVE}" AND EXISTS "${TZDB_LOCATION}"))
+    file(DOWNLOAD "https://data.iana.org/time-zones/releases/${TZDB_ARCHIVE}" "${CMAKE_CURRENT_BINARY_DIR}/${TZDB_ARCHIVE}")
+    file(ARCHIVE_EXTRACT INPUT "${CMAKE_CURRENT_BINARY_DIR}/${TZDB_ARCHIVE}" DESTINATION "${CMAKE_CURRENT_BINARY_DIR}")
+endif()
+
+set(TZDB_BUILD_DIR "${CMAKE_CURRENT_BINARY_DIR}/build")
+set(TZDB_ZONEINFO "${TZDB_BUILD_DIR}/usr/share/zoneinfo")
+set(TZIF_LIST_FILE "${CMAKE_CURRENT_BINARY_DIR}/tzif_list.txt")
+
+set(NX_BUILD_DIR "${CMAKE_CURRENT_BINARY_DIR}/nx")
+
+add_custom_target(x80e 
+    ALL
+    DEPENDS
+        tzdb2nx)
+
+if (NOT EXISTS "${TZDB_BUILD_DIR}" OR NOT EXISTS ${TZIF_LIST_FILE})
+    execute_process(
+        COMMAND
+            "${GNU_MAKE}" DESTDIR=${TZDB_BUILD_DIR} install
+        WORKING_DIRECTORY 
+            "${TZDB_LOCATION}"
+        COMMAND_ERROR_IS_FATAL ANY
+    )
+
+    # execute_process(
+    #     COMMAND
+    #         "${TZDB_LOCATION}/zic" -b fat -d ${TZDB_ZONEINFO} africa antarctica asia australasia europe northamerica southamerica etcetera backward factory
+    #     WORKING_DIRECTORY
+    #         "${TZDB_LOCATION}"
+    #     COMMAND_ERROR_IS_FATAL ANY
+    # )
+
+    execute_process(
+        COMMAND
+            /bin/bash "${CMAKE_CURRENT_SOURCE_DIR}/find_tzif.sh" "${TZDB_ZONEINFO}" "${TZIF_LIST_FILE}"
+        COMMAND_ERROR_IS_FATAL ANY
+    )
+endif()
+
+file(STRINGS "${TZIF_LIST_FILE}" TZ_FILES)
+foreach(FILE ${TZ_FILES})
+    file(RELATIVE_PATH TARG "${TZDB_ZONEINFO}" "${FILE}")
+    get_filename_component(TARG_PATH "${NX_BUILD_DIR}/${TARG}" DIRECTORY)
+    string(REGEX REPLACE "\/" "_" TARG_SANITIZED "${TARG}")
+    add_custom_target(${TARG_SANITIZED}
+        BYPRODUCTS
+            ${NX_BUILD_DIR}/${TARG}
+        COMMAND
+            mkdir -p ${TARG_PATH}
+        COMMAND
+            "${PROJECT_BINARY_DIR}/src/tzdb2nx/tzdb2nx" ${FILE} ${NX_BUILD_DIR}/${TARG}
+        DEPENDS
+            tzdb2nx
+    )
+
+    add_dependencies(x80e ${TARG_SANITIZED})
+endforeach()
diff --git a/src/tzdb/find_tzif.sh b/src/tzdb/find_tzif.sh
new file mode 100644
index 0000000..3a96a53
--- /dev/null
+++ b/src/tzdb/find_tzif.sh
@@ -0,0 +1,14 @@
+#/bin/bash
+set -e
+directory=$1
+tzif_list=$2
+
+truncate -s 0 $tzif_list
+
+for i in `find $directory -type f`; do
+    header=`head -c 4 $i`
+    if [ "$header" == "TZif" ]; then
+        echo "$i" >> $tzif_list
+    fi
+done
+