diff --git a/NEWS.md b/NEWS.md
index 9b87243..c208419 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,5 +1,17 @@
 # Major changes between releases
 
+## Changes in version 0.5 (UNRELEASED)
+
+Released on 2024/05/XX.
+
+* Use more modern autotools macros.  Bump the minimum autoconf version to 2.68 to
+  support this change.
+
+* Modify build code to improve Lua 5.4 support.
+
+* Replace `std::auto_ptr` use with `std::unique_ptr` use.  This improves C++
+  standard support and fixes the build with newer C++ standards.
+
 ## Changes in version 0.4
 
 Released on 2013/12/07.
diff --git a/configure.ac b/configure.ac
index 45cb5f2..cb3cb81 100644
--- a/configure.ac
+++ b/configure.ac
@@ -26,7 +26,7 @@ dnl THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 dnl (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 dnl OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-AC_INIT([Lutok], [0.4],
+AC_INIT([Lutok], [0.5],
         [testing@FreeBSD.org], [lutok],
         [https://github.com/freebsd/lutok/])
 AC_PREREQ([2.68])