In NixOS chroot builds, there is no root account. So configure should not rely on its existence in deciding whether to use getpwuid(). diff -rc -x '*~' rcs-5.7-orig/src/conf.sh rcs-5.7/src/conf.sh *** rcs-5.7-orig/src/conf.sh 1995-06-16 08:19:24.000000000 +0200 --- rcs-5.7/src/conf.sh 2010-02-12 15:22:37.000000000 +0100 *************** *** 821,827 **** a= z= cat >a.c <&2 --- 821,827 ---- a= z= cat >a.c <&2