diff --git a/openjdk-21.0.0.35-0.build.sh b/openjdk-21.0.0.35-0.build.sh
new file mode 100755
index 0000000..ad218ef
--- /dev/null
+++ b/openjdk-21.0.0.35-0.build.sh
@@ -0,0 +1,73 @@
+#! /bin/bash
+
+PKG=openjdk
+VERSION=21.0.0.35 # schema: major.minor.security.update
+BUILD=0
+
+PREFIX=/pkg/$PKG-$VERSION-$BUILD
+if [ -n "$TESTING" ]; then PREFIX=/scratch/local2/$PKG-$VERSION-$BUILD ; fi
+
+set -xe
+umask 022
+
+BUILD_TMPDIR=/scratch/local2/$PKG-$VERSION-$BUILD.$USER.build.tmp
+test -d $BUILD_TMPDIR && rm -rf $BUILD_TMPDIR
+mkdir -p $BUILD_TMPDIR/home
+export TMPDIR=$BUILD_TMPDIR
+export HOME=$BUILD_TMPDIR/home
+
+exec </dev/null
+
+mkdir -p $PREFIX
+cat >$PREFIX/profile <<-EOF
+	PATH=$PREFIX/bin:\$PATH
+	if [ -d $PREFIX/.compatlibs ]; then export LD_LIBRARY_PATH=$PREFIX/.compatlibs\${LD_LIBRARY_PATH:+:\$LD_LIBRARY_PATH} ; fi
+EOF
+. $PREFIX/profile
+
+BUILDDIR=$PREFIX/build
+
+mkdir -p $BUILDDIR
+cd $BUILDDIR
+
+
+# Install a precompiled bootstrap jdk first
+# src: https://download.java.net/java/GA/jdk21.0.1/415e3f918a1f4062a0074a2794853d0d/12/GPL/openjdk-21.0.1_linux-x64_bin.tar.gz
+# find the above via https://jdk.java.net/21/
+
+test -e openjdk-21.0.1_linux-x64_bin.tar.gz || wget \
+    https://beehive.molgen.mpg.de/80f727037c1346f0b5d30b84c32318df/openjdk-21.0.1_linux-x64_bin.tar.gz
+
+test -d bootjdk || (tar -xf openjdk-21.0.1_linux-x64_bin.tar.gz; mv jdk-21.0.1 bootjdk)
+
+# And now the real thing
+# src: https://github.com/openjdk/jdk/archive/refs/tags/jdk-21+35.tar.gz
+
+test -e jdk-21+35.tar.gz || wget \
+    https://beehive.molgen.mpg.de/57f94adacd3c79055587cce27e2d520f/jdk-21%2b35.tar.gz
+
+test -d jdk-jdk-21-35 || tar -xf jdk-21+35.tar.gz
+
+cd jdk-jdk-21-35
+mkdir -p jdkbuild
+cd jdkbuild
+
+bash ../configure \
+        --enable-unlimited-crypto=yes \
+        --disable-warnings-as-errors \
+        --with-native-debug-symbols=none \
+        --with-debug-level=release \
+        --with-stdc++lib=static \
+        --with-zlib=bundled \
+        --with-boot-jdk=$BUILDDIR/bootjdk \
+        --with-version-update=0 \
+        --with-version-build=35 \
+        --with-version-opt='' \
+        --with-log=info
+
+make images
+
+# install
+cp -a $BUILDDIR/jdk-jdk-21-35/jdkbuild/images/jdk/* $PREFIX
+
+exit