diff -rupN --no-dereference pbuilder-0.231/pbuilderrc pbuilder-0.231-new/pbuilderrc
--- pbuilder-0.231/pbuilderrc	2020-12-08 15:55:39.000000000 +0100
+++ pbuilder-0.231-new/pbuilderrc	2021-01-19 12:00:32.057136789 +0100
@@ -52,9 +52,6 @@ REMOVEPACKAGES=""
 #HOOKDIR="/usr/lib/pbuilder/hooks"
 HOOKDIR=""
 EATMYDATA=no
-# NB: this var is private to pbuilder; ccache uses "CCACHE_DIR" instead
-# CCACHEDIR="/var/cache/pbuilder/ccache"
-CCACHEDIR=""
 
 # make debconf not interact with user
 export DEBIAN_FRONTEND="noninteractive"
@@ -108,8 +105,8 @@ DEBBUILDOPTS="${DEBBUILDOPTS}"
 APTCONFDIR=""
 
 # the username and ID used by pbuilder, inside chroot. Needs fakeroot, really
-BUILDUSERID=1234
 BUILDUSERNAME=pbuilder
+BUILDUSERID=$(grep $BUILDUSERNAME /etc/passwd | cut -d: -f3)
 
 # BINDMOUNTS is a space separated list of things to mount
 # inside the chroot.
@@ -154,3 +151,12 @@ COMPRESSPROG="gzip"
 # exists and contains one of the copied files (without the leading /etc) that
 # file will be copied from here instead of the system one
 CONFDIR="/etc/pbuilder/conf_files"
+
+# ccache (make sure ccache is installed before uncommenting)
+CCACHEDIR=""
+# Note: CCACHEDIR is private to pbuilder, ccache uses "CCACHE_DIR"
+#CCACHEDIR="/var/cache/pbuilder/ccache"
+#export CCACHE_DIR="${CCACHEDIR}"
+#export PATH="/usr/lib/ccache:${PATH}"
+#EXTRAPACKAGES=ccache
+#BINDMOUNTS="${BINDMOUNTS} ${CCACHE_DIR}"