diff --git a/gis/python3-netcdf4-python/python3-netcdf4-python.SlackBuild b/gis/python3-netcdf4-python/python3-netcdf4-python.SlackBuild
index 908be04c4e..1ae1f1e354 100644
--- a/gis/python3-netcdf4-python/python3-netcdf4-python.SlackBuild
+++ b/gis/python3-netcdf4-python/python3-netcdf4-python.SlackBuild
@@ -2,7 +2,7 @@
 
 # Slackware build script for python3-netcdf4-python
 
-# Copyright 2022 - Gregory J. L. Tourte <artourter@gmail.com>
+# Copyright 2022-2023 - Gregory J. L. Tourte <artourter@gmail.com>
 # All rights reserved.
 #
 # Redistribution and use of this script, with or without modification, is
@@ -25,13 +25,13 @@
 cd $(dirname $0) ; CWD=$(pwd)
 
 PRGNAM=python3-netcdf4-python
-VERSION=${VERSION:-1.6.2}
+VERSION=${VERSION:-1.6.4}
 BUILD=${BUILD:-1}
 TAG=${TAG:-_SBo}
 PKGTYPE=${PKGTYPE:-tgz}
 
 SRCNAM=netcdf4-python
-SRCVER=${VERSION}
+SRCVER=${VERSION}rel
 
 if [ -z "$ARCH" ]; then
   case "$( uname -m )" in
@@ -50,20 +50,6 @@ TMP=${TMP:-/tmp/SBo}
 PKG=$TMP/package-$PRGNAM
 OUTPUT=${OUTPUT:-/tmp}
 
-if [ "$ARCH" = "i586" ]; then
-  SLKCFLAGS="-O2 -march=i586 -mtune=i686"
-  LIBDIRSUFFIX=""
-elif [ "$ARCH" = "i686" ]; then
-  SLKCFLAGS="-O2 -march=i686 -mtune=i686"
-  LIBDIRSUFFIX=""
-elif [ "$ARCH" = "x86_64" ]; then
-  SLKCFLAGS="-O2 -fPIC"
-  LIBDIRSUFFIX="64"
-else
-  SLKCFLAGS="-O2"
-  LIBDIRSUFFIX=""
-fi
-
 set -e
 
 rm -rf $PKG
@@ -79,7 +65,18 @@ find -L . \
   \( -perm 666 -o -perm 664 -o -perm 640 -o -perm 600 -o -perm 444 \
   -o -perm 440 -o -perm 400 \) -exec chmod 644 {} \;
 
-python3 setup.py install --root=$PKG
+# Fixing numpy dependency check in pyproject.toml:
+# oldest-supported-numpy has a strict check and doesn't support newer version
+# so we replace it. The alternative is to add --skip-dependency-check to tbe
+# build line but this is not deemed optimal.
+sed -i 's/oldest-supported-numpy/numpy>=1.19.3/' pyproject.toml
+
+# Requires newer version of setuptools than available in -stable. Has not
+# effect on -current
+export PYTHONPATH=/opt/python3.9/site-packages
+
+python3 -m build --no-isolation
+python3 -m installer -d "$PKG" dist/*.whl
 
 find $PKG -print0 | xargs -0 file | grep -e "executable" -e "shared object" | grep ELF \
   | cut -f 1 -d : | xargs strip --strip-unneeded 2> /dev/null || true
diff --git a/gis/python3-netcdf4-python/python3-netcdf4-python.info b/gis/python3-netcdf4-python/python3-netcdf4-python.info
index 199da885b7..d9ffbff76a 100644
--- a/gis/python3-netcdf4-python/python3-netcdf4-python.info
+++ b/gis/python3-netcdf4-python/python3-netcdf4-python.info
@@ -1,10 +1,10 @@
 PRGNAM="python3-netcdf4-python"
-VERSION="1.6.2"
+VERSION="1.6.4"
 HOMEPAGE="http://unidata.github.io/netcdf4-python/"
-DOWNLOAD="https://github.com/Unidata/netcdf4-python/archive/v1.6.2/netcdf4-python-1.6.2.tar.gz"
-MD5SUM="8a1dd0489bc56a982014b0dc86d1f3c2"
+DOWNLOAD="https://github.com/Unidata/netcdf4-python/archive/v1.6.4rel/netcdf4-python-1.6.4rel.tar.gz"
+MD5SUM="f377d9da6641272c2dc435ceab1c6209"
 DOWNLOAD_x86_64=""
 MD5SUM_x86_64=""
-REQUIRES="netcdf python3-cftime"
+REQUIRES="netcdf python3-cftime python3-setuptools-opt"
 MAINTAINER="ArTourter"
 EMAIL="artourter@gmail.com"