diff --git a/CMakeLists.txt b/CMakeLists.txt
new file mode 100644
index 0000000..38268e4
--- /dev/null
+++ b/CMakeLists.txt
@@ -0,0 +1,216 @@
+cmake_minimum_required (VERSION 3.0.2)
+project (cjose)
+
+include(CheckSymbolExists)
+include(CheckIncludeFile)
+include(CheckTypeSize) 
+
+option(ENABLE_Tests "Turn on Tests" ON)
+option(CJOSE_BUILD_SHARED_LIBS "Build shared libraries." OFF)
+
+list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_LIST_DIR}/CMakeModules")
+
+# Build Release by default
+if (NOT CMAKE_BUILD_TYPE)
+set(CMAKE_BUILD_TYPE Release)
+else()
+endif()
+
+# Setup cjose version
+set(CJOSE_MAJOR_VERSION 0)
+set(CJOSE_MINOR_VERSION 4)
+set(CJOSE_PATCH_VERSION 1)
+set(PACKAGE_VERSION ${CJOSE_MAJOR_VERSION}.${CJOSE_MINOR_VERSION}.${CJOSE_PATCH_VERSION})
+  
+# Set output directories
+set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${PROJECT_BINARY_DIR}/bin)
+set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${PROJECT_BINARY_DIR}/lib)
+set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${PROJECT_BINARY_DIR}/lib)
+
+# Create version.h file
+configure_file (
+  "${PROJECT_SOURCE_DIR}/include/cjose/version.h.in"
+  "${PROJECT_BINARY_DIR}/include/cjose/version.h"
+  )
+
+# Set include directories  
+include_directories(
+${CMAKE_CURRENT_SOURCE_DIR}/include
+${CMAKE_CURRENT_SOURCE_DIR}/src/include
+${CMAKE_CURRENT_SOURCE_DIR}/src
+)
+
+# Find dependencies
+# Look for Homebrew version of OpenSSL
+function(GetRootDirForHomebrew PKG_NAME)
+    if ((NOT ${PKG_NAME}_INCLUDE_DIR) OR (NOT ${PKG_NAME}_LIBRARIES))
+        string(TOLOWER ${PKG_NAME} PKG_NAME_LOWER)
+        SET(BREW_PACKAGE_DIR /usr/local/Cellar/${PKG_NAME_LOWER})
+        IF (EXISTS ${BREW_PACKAGE_DIR})
+            file(GLOB HB_${PKG_NAME}_ROOT_DIRECTORIES ${BREW_PACKAGE_DIR}/*)
+            list(GET HB_${PKG_NAME}_ROOT_DIRECTORIES 0 HB_${PKG_NAME}_ROOT_DIR)
+            if(HB_${PKG_NAME}_ROOT_DIRECTORIES AND NOT ${PKG_NAME}_ROOT_DIR)
+                SET(${PKG_NAME}_ROOT_DIR ${HB_${PKG_NAME}_ROOT_DIR} PARENT_SCOPE)
+            endif(HB_${PKG_NAME}_ROOT_DIRECTORIES AND NOT ${PKG_NAME}_ROOT_DIR)
+        ENDIF (EXISTS ${BREW_PACKAGE_DIR})
+    endif((NOT ${PKG_NAME}_INCLUDE_DIR) OR (NOT ${PKG_NAME}_LIBRARIES))
+endfunction(GetRootDirForHomebrew PKG_NAME)
+
+if(CMAKE_C_COMPILER_ID MATCHES "AppleClang")
+    GetRootDirForHomebrew(OPENSSL)
+    if (ENABLE_Tests)
+        GetRootDirForHomebrew(CHECK)
+    endif()
+    GetRootDirForHomebrew(JANSSON)
+endif(CMAKE_C_COMPILER_ID MATCHES "AppleClang")
+
+find_package(Check 0.9.4)
+
+find_library(RT NAMES rt)
+if (${RT} STREQUAL RT-NOTFOUND)
+	unset(${RT})
+endif(${RT} STREQUAL RT-NOTFOUND)
+
+find_library(M NAMES m)
+if (${M} STREQUAL M-NOTFOUND)
+	unset(${M})
+endif(${M} STREQUAL M-NOTFOUND)
+
+check_type_size(ssize_t SSIZE_T)
+
+# Enable test if possible
+if (NOT CHECK_FOUND OR ENABLE_Tests==OFF)
+	SET(ENABLE_Tests OFF)
+endif(NOT CHECK_FOUND OR ENABLE_Tests==OFF)
+message(STATUS "Tests Enabled............${ENABLE_Tests}")
+
+CHECK_SYMBOL_EXISTS("random" stdlib.h HAVE_RANDOM)
+
+# Set dependency include directories
+include_directories(
+  ${OPENSSL_INCLUDE_DIR}
+  ${JANSSON_INCLUDE_DIR}
+  ${BUILD_INCLUDES}
+)
+
+#Generate config file
+configure_file (
+  "${PROJECT_SOURCE_DIR}/include/cjose/config.h.in"
+  "${PROJECT_BINARY_DIR}/include/cjose/cjose_config.h"
+)
+
+# Setup compilation flags for different compilers
+if (MSVC)
+   add_compile_options(/W2  /nologo /WX-)
+   add_definitions( "/DVERSION=\"${PACKAGE_VERSION}\"")
+   add_definitions( "/D_CRT_SECURE_NO_WARNINGS")
+   set(DEFAULT_COMPILER_OPTIONS /Zi /DEBUG $<$<CONFIG:Debug>:/Od> $<$<CONFIG:Release>:/O2> /MP )
+   set(LIB_COMPILER_OPTIONS ${DEFAULT_COMPILER_OPTIONS} /WX)
+   if (STATIC_CRT)
+      SET(LIB_COMPILER_OPTIONS ${LIB_COMPILER_OPTIONS} $<$<CONFIG:Debug>:/MTd> $<$<CONFIG:Release>:/MT>)
+   else()
+      SET(LIB_COMPILER_OPTIONS ${LIB_COMPILER_OPTIONS} $<$<CONFIG:Debug>:/MDd> $<$<CONFIG:Release>:/MD>)
+   endif()
+elseif(CMAKE_COMPILER_IS_GNUCC)
+	add_definitions( "-DVERSION=\"${PACKAGE_VERSION}\"")
+    set(DEFAULT_COMPILER_OPTIONS -std=gnu99 -g $<$<CONFIG:Release>:-O2>)
+	set(LIB_COMPILER_OPTIONS ${DEFAULT_COMPILER_OPTIONS} --pedantic -Wall -Werror)
+else(CMAKE_C_COMPILER_ID MATCHES "AppleClang")
+	add_definitions( "-DVERSION=\"${PACKAGE_VERSION}\"")
+    set(DEFAULT_COMPILER_OPTIONS -std=gnu99 -g $<$<CONFIG:Release>:-O2>)
+	set(LIB_COMPILER_OPTIONS ${DEFAULT_COMPILER_OPTIONS} --pedantic -Wall -Werror)
+endif(MSVC)
+
+
+file(GLOB CJOSE_SRC ${PROJECT_SOURCE_DIR}/src/*.c)
+file(GLOB CJOSE_HDR_PUBLIC ${PROJECT_SOURCE_DIR}/include/cjose/*.h)
+file(GLOB CJOSE_HDR_PRIVATE ${PROJECT_SOURCE_DIR}/src/include/*.h)
+
+source_group("Library Sources" FILES ${CJOSE_SRC})
+source_group("Library Private Headers" FILES ${CJOSE_HDR_PRIVATE})
+source_group("Library Public Headers" FILES ${CJOSE_HDR_PUBLIC})
+
+if (CJOSE_BUILD_SHARED_LIBS)
+add_library(cjose SHARED 
+${CJOSE_SRC}
+${CJOSE_HDR_PRIVATE}
+${CJOSE_HDR_PUBLIC}
+)
+else()
+add_library(cjose 
+${CJOSE_SRC}
+${CJOSE_HDR_PRIVATE}
+${CJOSE_HDR_PUBLIC}
+)
+endif()
+
+target_link_libraries(cjose ${JANSSON_LIBRARIES} ${OPENSSL_LIBRARIES} ${MLIB} ${RTLIB})
+target_compile_options(cjose PRIVATE ${LIB_COMPILER_OPTIONS})
+
+if (ENABLE_Tests)
+file(GLOB CJOSE_TESTS_SRC ${PROJECT_SOURCE_DIR}/test/*.c)
+file(GLOB CJOSE_TESTS_HDR ${PROJECT_SOURCE_DIR}/test/*.h)
+include_directories(${CHECK_INCLUDE_DIRS})
+source_group("Test Files " FILES ${CJOSE_TESTS_SRC} ${CJOSE_TESTS_HDR})
+
+add_executable(tests ${CJOSE_TESTS_SRC} ${CJOSE_TESTS_HDR})
+target_compile_options(tests PRIVATE ${DEFAULT_COMPILER_OPTIONS})
+target_link_libraries(tests cjose ${JANSSON_LIBRARIES} ${OPENSSL_LIBRARIES} ${CHECK_LIBRARIES})
+endif(ENABLE_Tests)
+
+#install
+
+# Allow the user to override installation directories.
+set(CJOSE_INSTALL_LIB_DIR       lib CACHE PATH "Installation directory for libraries")
+set(CJOSE_INSTALL_BIN_DIR       bin CACHE PATH "Installation directory for executables")
+set(CJOSE_INSTALL_INCLUDE_DIR   include CACHE PATH "Installation directory for header files")
+
+
+if(WIN32 AND NOT CYGWIN)
+  set(DEF_INSTALL_CMAKE_DIR cmake)
+else()
+  set(DEF_INSTALL_CMAKE_DIR lib/cmake/cjose)
+endif()
+
+set(CJOSE_INSTALL_CMAKE_DIR ${DEF_INSTALL_CMAKE_DIR} CACHE PATH "Installation directory for CMake files")
+
+# Create pkg-conf file.
+# (We use the same files as ./configure does, so we
+#  have to defined the same variables used there).
+set(prefix      ${CMAKE_INSTALL_PREFIX})
+set(exec_prefix ${CMAKE_INSTALL_PREFIX})
+set(libdir      ${CMAKE_INSTALL_PREFIX}/${CMAKE_INSTALL_LIBDIR})
+set(includedir  ${CMAKE_INSTALL_PREFIX}/${CJOSE_INSTALL_INCLUDE_DIR})
+set(VERSION     ${PACKAGE_VERSION})
+configure_file(${CMAKE_CURRENT_SOURCE_DIR}/cjose.pc.in
+               ${CMAKE_CURRENT_BINARY_DIR}/cjose.pc @ONLY)
+			   
+# Make sure the paths are absolute.
+foreach(p LIB BIN INCLUDE CMAKE)
+    set(var CJOSE_INSTALL_${p}_DIR)
+    if(NOT IS_ABSOLUTE "${${var}}")
+        set(${var} "${CMAKE_INSTALL_PREFIX}/${${var}}")
+    endif()
+endforeach()
+
+set_target_properties(cjose PROPERTIES PUBLIC_HEADER "${CJOSE_HDR_PUBLIC}")
+
+
+# Install the pkg-config.
+install (FILES 
+         ${CMAKE_CURRENT_BINARY_DIR}/cjose.pc
+         DESTINATION ${CJOSE_INSTALL_LIB_DIR}/pkgconfig COMPONENT dev)
+		 
+install(TARGETS cjose
+        EXPORT CjoseTargets
+        LIBRARY DESTINATION "${CJOSE_INSTALL_LIB_DIR}" COMPONENT lib
+        ARCHIVE DESTINATION "${CJOSE_INSTALL_LIB_DIR}" COMPONENT lib
+        RUNTIME DESTINATION "${CJOSE_INSTALL_BIN_DIR}" COMPONENT lib # Windows DLLs
+        PUBLIC_HEADER DESTINATION "${CJOSE_INSTALL_INCLUDE_DIR}/cjose" COMPONENT dev)
+
+# Install exports for the install-tree.
+install(EXPORT CjoseTargets 
+        DESTINATION "${CJOSE_INSTALL_CMAKE_DIR}" COMPONENT dev)
+
+# For use when simply using add_library from a parent project to build cjose.
+set(CJOSE_LIBRARIES cjose CACHE STRING "Cjose libraries")
diff --git a/CMakeModules/FindCheck.cmake b/CMakeModules/FindCheck.cmake
new file mode 100644
index 0000000..7f196a5
--- /dev/null
+++ b/CMakeModules/FindCheck.cmake
@@ -0,0 +1,72 @@
+if (CHECK_LIBRARIES AND CHECK_INCLUDE_DIRS)
+  set(CHECK_FOUND TRUE)
+else (CHECK_LIBRARIES AND CHECK_INCLUDE_DIRS)
+  find_path(CHECK_INCLUDE_DIR
+    NAMES
+      check.h
+    PATHS
+      ${CHECK_ROOT_DIR}/include
+    NO_DEFAULT_PATH
+  )
+
+  find_path(CHECK_INCLUDE_DIR
+    NAMES
+      check.h
+  )
+
+find_library(CHECK_LIBRARY_CHECK
+    NAMES
+      check
+      compat
+    PATHS
+    ${CHECK_ROOT_DIR}/lib
+    NO_DEFAULT_PATH
+  )
+
+find_library(CHECK_LIBRARY_CHECK
+    NAMES
+      check
+      compat
+  )
+
+find_library(CHECK_LIBRARY_COMPAT
+    NAMES
+      compat
+    PATHS
+    ${CHECK_ROOT_DIR}/lib
+    NO_DEFAULT_PATH
+  )
+
+find_library(CHECK_LIBRARY_COMPAT
+    NAMES
+      compat
+  )
+
+if (CHECK_INCLUDE_DIR)
+set(CHECK_INCLUDE_DIRS
+  ${CHECK_INCLUDE_DIRS}
+  ${CHECK_INCLUDE_DIR}
+  )
+endif(CHECK_INCLUDE_DIR)
+
+if (CHECK_LIBRARY_CHECK)
+  set(CHECK_LIBRARIES
+    ${CHECK_LIBRARIES}
+    ${CHECK_LIBRARY_CHECK}
+    )
+endif (CHECK_LIBRARY_CHECK)
+
+if (CHECK_LIBRARY_COMPAT)
+  set(CHECK_LIBRARIES
+    ${CHECK_LIBRARIES}
+    ${CHECK_LIBRARY_COMPAT}
+    )
+endif (CHECK_LIBRARY_COMPAT)
+
+  include(FindPackageHandleStandardArgs)
+  find_package_handle_standard_args(Check DEFAULT_MSG
+    CHECK_LIBRARIES CHECK_INCLUDE_DIRS)
+
+  mark_as_advanced(CHECK_INCLUDE_DIRS CHECK_LIBRARIES)
+
+endif (CHECK_LIBRARIES AND CHECK_INCLUDE_DIRS)
diff --git a/CMakeModules/FindJansson.cmake b/CMakeModules/FindJansson.cmake
new file mode 100644
index 0000000..ae34c52
--- /dev/null
+++ b/CMakeModules/FindJansson.cmake
@@ -0,0 +1,68 @@
+if (JANSSON_LIBRARIES AND JANSSON_INCLUDE_DIRS)
+  set(JANSSON_FOUND TRUE)
+else (JANSSON_LIBRARIES AND JANSSON_INCLUDE_DIRS)
+  find_path(JANSSON_INCLUDE_DIR
+    NAMES
+      jansson.h
+    PATHS
+      ${JANSSON_ROOT_DIR}/include
+    NO_DEFAULT_PATH
+  )
+
+  find_path(JANSSON_INCLUDE_DIR
+    NAMES
+      jansson.h
+  )
+
+find_library(JANSSON_LIBRARY_RELEASE
+    NAMES
+      jansson
+    PATHS
+      ${JANSSON_ROOT_DIR}/lib
+    NO_DEFAULT_PATH
+  )
+
+find_library(JANSSON_LIBRARY_RELEASE
+    NAMES
+      jansson
+  )
+
+find_library(JANSSON_LIBRARY_DEBUG
+    NAMES
+      jansson_d
+    PATHS
+      ${JANSSON_ROOT_DIR}/lib
+    NO_DEFAULT_PATH
+  )
+
+find_library(JANSSON_LIBRARY_DEBUG
+    NAMES
+      jansson_d
+  )
+
+set(JANSSON_INCLUDE_DIRS
+  ${JANSSON_INCLUDE_DIR}
+  )
+
+if (JANSSON_LIBRARY_DEBUG)
+  set(JANSSON_LIBRARIES
+    ${JANSSON_LIBRARIES}
+    debug ${JANSSON_LIBRARY_DEBUG}
+    )
+endif (JANSSON_LIBRARY_DEBUG)
+
+if (JANSSON_LIBRARY_RELEASE)
+  if (WIN32)
+    set(JANSSON_LIBRARIES ${JANSSON_LIBRARIES} optimized ${JANSSON_LIBRARY_RELEASE})
+  else()
+  	set(JANSSON_LIBRARIES ${JANSSON_LIBRARIES} general ${JANSSON_LIBRARY_RELEASE})
+  endif(WIN32)
+endif (JANSSON_LIBRARY_RELEASE)
+
+  include(FindPackageHandleStandardArgs)
+  find_package_handle_standard_args(Jansson DEFAULT_MSG
+    JANSSON_LIBRARIES JANSSON_INCLUDE_DIRS)
+
+  mark_as_advanced(JANSSON_INCLUDE_DIRS JANSSON_LIBRARIES)
+
+endif (JANSSON_LIBRARIES AND JANSSON_INCLUDE_DIRS)
diff --git a/include/cjose/cjose.h b/include/cjose/cjose.h
index 79bcd53..2328550 100644
--- a/include/cjose/cjose.h
+++ b/include/cjose/cjose.h
@@ -19,7 +19,6 @@
 #ifndef CJOSE_CJOSE_H
 #define CJOSE_CJOSE_H
 
-#include "version.h"
 #include "error.h"
 #include "base64.h"
 #include "header.h"
diff --git a/include/cjose/config.h.in b/include/cjose/config.h.in
new file mode 100644
index 0000000..a2d004f
--- /dev/null
+++ b/include/cjose/config.h.in
@@ -0,0 +1,14 @@
+#pragma once
+#ifndef CONFIG_H
+#define CONFIG_H
+
+#cmakedefine HAVE_RANDOM
+
+#cmakedefine HAVE_SSIZE_T
+
+#ifndef HAVE_SSIZE_T
+#undef ssize_t
+typedef int ssize_t;
+#endif
+
+#endif
diff --git a/src/include/util_int.h b/src/include/util_int.h
index c8d059c..c4ad01b 100644
--- a/src/include/util_int.h
+++ b/src/include/util_int.h
@@ -9,6 +9,7 @@
 #define SRC_UTIL_INT_H
 
 #include <cjose/error.h>
+#include <cjose/cjose_config.h>
 
 #include <jansson.h>
 #include <string.h>
diff --git a/src/jwk.c b/src/jwk.c
index 860f0e7..52ae6a9 100644
--- a/src/jwk.c
+++ b/src/jwk.c
@@ -1321,7 +1321,7 @@ _decode_json_object_base64url_attribute(json_t *jwk_json, const char *key, uint8
         for (end = str + strlen(str) - 1; *end == '=' && end > str; --end)
             ;
         size_t unpadded_len = end + 1 - str - ((*end == '=') ? 1 : 0);
-        size_t expected_len = ceil(4 * ((float)*buflen / 3));
+        size_t expected_len = (size_t)ceil(4 * ((float)*buflen / 3));
 
         if (expected_len != unpadded_len)
         {