If you do:
git clone https://git.taler.net/gnurl.git
cd gnurl
guix environment gnurl -- ./buildconf
sed 's/\/usr\/bin\/file/\/usr\/bin\/env file/' configure
guix environment gnurl -- ./configure --enable-ipv6 --with-gnutls --without-libssh2 --without-libmetalink --without-winidn --without-librtmp --without-nghttp2 --without-nss --without-cyassl --without-polarssl --without-ssl --without-winssl --without-darwinssl --disable-sspi --disable-ntlm-wb --disable-ldap --disable-rtsp --disable-dict --disable-telnet --disable-tftp --disable-pop3 --disable-imap --disable-smtp --disable-gopher --disable-file --disable-ftp --disable-smb
guix environment gnurl -- make
guix environment gnurl zip xz perl git -- ./maketgz 7.55.1-4

and the extract the resulting gnurl-7.55.1-4.tar.xz somewhere
you can cat ltmain.sh:

#!/gnu/store/kpxi8h3669afr9r1bgvaf9ij3y4wdyyn-bash-minimal-4.4.12/bin/sh
## DO NOT EDIT - This file generated from ./build-aux/ltmain.in
##               by inline-source v2014-01-03.01

# libtool (GNU libtool) 2.4.6
# Provide generalized library-building support services.
# Written by Gordon Matzigkeit <gord@gnu.ai.mit.edu>, 1996
…

This is the only result when I grep for /gnu/store/.
Is this caused by our autotools or by the way I
produced the tarball?
What needs to be changed to remove this?
Adding something to rewrite the shebang in the maketgz
script is trivial, I'm just wondering if it was some
argument I used.
This is close to 'make dist', as make dist is involved
in maketgz.

Help is very much welcome!
-- 
ng0
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